Make LabelType an AutoValue

Change-Id: I517b0d7cc66a9630c8c045e5352338cd033a01a3
diff --git a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
index 1dbeb70..dfb7a55 100644
--- a/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
+++ b/java/com/google/gerrit/acceptance/AbstractDaemonTest.java
@@ -1442,10 +1442,10 @@
       LabelValue... value)
       throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = label(label, value);
+      LabelType.Builder labelType = label(label, value).toBuilder();
       labelType.setFunction(func);
-      labelType.setRefPatterns(refPatterns);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      labelType.setRefPatterns(ImmutableList.copyOf(refPatterns));
+      u.getConfig().upsertLabelType(labelType.build());
       u.save();
     }
   }
diff --git a/java/com/google/gerrit/common/data/LabelType.java b/java/com/google/gerrit/common/data/LabelType.java
index 3a68414..9c1423d 100644
--- a/java/com/google/gerrit/common/data/LabelType.java
+++ b/java/com/google/gerrit/common/data/LabelType.java
@@ -14,23 +14,21 @@
 
 package com.google.gerrit.common.data;
 
-import static com.google.common.collect.ImmutableList.toImmutableList;
 import static java.util.Comparator.comparing;
-import static java.util.stream.Collectors.collectingAndThen;
 import static java.util.stream.Collectors.toList;
 
+import com.google.auto.value.AutoValue;
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
 import com.google.gerrit.common.Nullable;
 import com.google.gerrit.entities.LabelId;
 import com.google.gerrit.entities.PatchSetApproval;
 import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Collections;
-import java.util.HashMap;
 import java.util.List;
-import java.util.Map;
 
-public class LabelType {
+@AutoValue
+public abstract class LabelType {
   public static final boolean DEF_ALLOW_POST_SUBMIT = true;
   public static final boolean DEF_CAN_OVERRIDE = true;
   public static final boolean DEF_COPY_ALL_SCORES_IF_NO_CHANGE = true;
@@ -46,12 +44,12 @@
   public static LabelType withDefaultValues(String name) {
     checkName(name);
     List<LabelValue> values = new ArrayList<>(2);
-    values.add(new LabelValue((short) 0, "Rejected"));
-    values.add(new LabelValue((short) 1, "Approved"));
-    return new LabelType(name, values);
+    values.add(LabelValue.create((short) 0, "Rejected"));
+    values.add(LabelValue.create((short) 1, "Approved"));
+    return create(name, values);
   }
 
-  public static String checkName(String name) {
+  public static String checkName(String name) throws IllegalArgumentException {
     checkNameInternal(name);
     if ("SUBM".equals(name)) {
       throw new IllegalArgumentException("Reserved label name \"" + name + "\"");
@@ -59,7 +57,7 @@
     return name;
   }
 
-  public static String checkNameInternal(String name) {
+  public static String checkNameInternal(String name) throws IllegalArgumentException {
     if (name == null || name.isEmpty()) {
       throw new IllegalArgumentException("Empty label name");
     }
@@ -76,270 +74,135 @@
     return name;
   }
 
-  private static List<LabelValue> sortValues(List<LabelValue> values) {
-    values = new ArrayList<>(values);
+  private static ImmutableList<LabelValue> sortValues(List<LabelValue> values) {
     if (values.isEmpty()) {
-      return Collections.emptyList();
+      return ImmutableList.of();
     }
     values = values.stream().sorted(comparing(LabelValue::getValue)).collect(toList());
     short v = values.get(0).getValue();
     short i = 0;
-    ArrayList<LabelValue> result = new ArrayList<>();
+    ImmutableList.Builder<LabelValue> result = ImmutableList.builder();
     // Fill in any missing values with empty text.
     while (i < values.size()) {
       while (v < values.get(i).getValue()) {
-        result.add(new LabelValue(v++, ""));
+        result.add(LabelValue.create(v++, ""));
       }
       v++;
       result.add(values.get(i++));
     }
-    result.trimToSize();
-    return Collections.unmodifiableList(result);
+    return result.build();
   }
 
-  protected String name;
+  public abstract String getName();
 
-  protected LabelFunction function;
+  public abstract LabelFunction getFunction();
 
-  protected boolean copyAnyScore;
-  protected boolean copyMinScore;
-  protected boolean copyMaxScore;
-  protected boolean copyAllScoresOnMergeFirstParentUpdate;
-  protected boolean copyAllScoresOnTrivialRebase;
-  protected boolean copyAllScoresIfNoCodeChange;
-  protected boolean copyAllScoresIfNoChange;
-  protected ImmutableList<Short> copyValues;
-  protected boolean allowPostSubmit;
-  protected boolean ignoreSelfApproval;
-  protected short defaultValue;
+  public abstract boolean isCopyAnyScore();
 
-  protected List<LabelValue> values;
-  protected short maxNegative;
-  protected short maxPositive;
+  public abstract boolean isCopyMinScore();
 
-  private transient boolean canOverride;
-  private transient List<String> refPatterns;
-  private transient Map<Short, LabelValue> byValue;
+  public abstract boolean isCopyMaxScore();
 
-  protected LabelType() {}
+  public abstract boolean isCopyAllScoresOnMergeFirstParentUpdate();
 
-  public LabelType(String name, List<LabelValue> valueList) {
-    this.name = checkName(name);
-    canOverride = true;
-    values = sortValues(valueList);
-    defaultValue = 0;
+  public abstract boolean isCopyAllScoresOnTrivialRebase();
 
-    function = LabelFunction.MAX_WITH_BLOCK;
+  public abstract boolean isCopyAllScoresIfNoCodeChange();
 
-    maxNegative = Short.MIN_VALUE;
-    maxPositive = Short.MAX_VALUE;
-    if (!values.isEmpty()) {
-      if (values.get(0).getValue() < 0) {
-        maxNegative = values.get(0).getValue();
-      }
-      if (values.get(values.size() - 1).getValue() > 0) {
-        maxPositive = values.get(values.size() - 1).getValue();
-      }
-    }
-    setCanOverride(DEF_CAN_OVERRIDE);
-    setCopyAllScoresIfNoChange(DEF_COPY_ALL_SCORES_IF_NO_CHANGE);
-    setCopyAllScoresIfNoCodeChange(DEF_COPY_ALL_SCORES_IF_NO_CODE_CHANGE);
-    setCopyAllScoresOnTrivialRebase(DEF_COPY_ALL_SCORES_ON_TRIVIAL_REBASE);
-    setCopyAllScoresOnMergeFirstParentUpdate(DEF_COPY_ALL_SCORES_ON_MERGE_FIRST_PARENT_UPDATE);
-    setCopyAnyScore(DEF_COPY_ANY_SCORE);
-    setCopyMaxScore(DEF_COPY_MAX_SCORE);
-    setCopyMinScore(DEF_COPY_MIN_SCORE);
-    setCopyValues(DEF_COPY_VALUES);
-    setAllowPostSubmit(DEF_ALLOW_POST_SUBMIT);
-    setIgnoreSelfApproval(DEF_IGNORE_SELF_APPROVAL);
+  public abstract boolean isCopyAllScoresIfNoChange();
 
-    byValue = new HashMap<>();
-    for (LabelValue v : values) {
-      byValue.put(v.getValue(), v);
-    }
+  public abstract ImmutableList<Short> getCopyValues();
+
+  public abstract boolean isAllowPostSubmit();
+
+  public abstract boolean isIgnoreSelfApproval();
+
+  public abstract short getDefaultValue();
+
+  public abstract ImmutableList<LabelValue> getValues();
+
+  public abstract short getMaxNegative();
+
+  public abstract short getMaxPositive();
+
+  public abstract boolean isCanOverride();
+
+  @Nullable
+  public abstract ImmutableList<String> getRefPatterns();
+
+  public abstract ImmutableMap<Short, LabelValue> getByValue();
+
+  public static LabelType create(String name, List<LabelValue> valueList) {
+    return LabelType.builder(name, valueList).build();
   }
 
-  public String getName() {
-    return name;
-  }
-
-  public void setName(String name) {
-    this.name = checkName(name);
+  public static LabelType.Builder builder(String name, List<LabelValue> valueList) {
+    return (new AutoValue_LabelType.Builder())
+        .setName(name)
+        .setValues(valueList)
+        .setDefaultValue((short) 0)
+        .setFunction(LabelFunction.MAX_WITH_BLOCK)
+        .setMaxNegative(Short.MIN_VALUE)
+        .setMaxPositive(Short.MAX_VALUE)
+        .setCanOverride(DEF_CAN_OVERRIDE)
+        .setCopyAllScoresIfNoChange(DEF_COPY_ALL_SCORES_IF_NO_CHANGE)
+        .setCopyAllScoresIfNoCodeChange(DEF_COPY_ALL_SCORES_IF_NO_CODE_CHANGE)
+        .setCopyAllScoresOnTrivialRebase(DEF_COPY_ALL_SCORES_ON_TRIVIAL_REBASE)
+        .setCopyAllScoresOnMergeFirstParentUpdate(DEF_COPY_ALL_SCORES_ON_MERGE_FIRST_PARENT_UPDATE)
+        .setCopyAnyScore(DEF_COPY_ANY_SCORE)
+        .setCopyMaxScore(DEF_COPY_MAX_SCORE)
+        .setCopyMinScore(DEF_COPY_MIN_SCORE)
+        .setCopyValues(DEF_COPY_VALUES)
+        .setAllowPostSubmit(DEF_ALLOW_POST_SUBMIT)
+        .setIgnoreSelfApproval(DEF_IGNORE_SELF_APPROVAL);
   }
 
   public boolean matches(PatchSetApproval psa) {
-    return psa.labelId().get().equalsIgnoreCase(name);
-  }
-
-  public LabelFunction getFunction() {
-    return function;
-  }
-
-  public void setFunction(@Nullable LabelFunction function) {
-    this.function = function;
-  }
-
-  public boolean canOverride() {
-    return canOverride;
-  }
-
-  @Nullable
-  public List<String> getRefPatterns() {
-    return refPatterns;
-  }
-
-  public void setCanOverride(boolean canOverride) {
-    this.canOverride = canOverride;
-  }
-
-  public boolean allowPostSubmit() {
-    return allowPostSubmit;
-  }
-
-  public void setAllowPostSubmit(boolean allowPostSubmit) {
-    this.allowPostSubmit = allowPostSubmit;
-  }
-
-  public boolean ignoreSelfApproval() {
-    return ignoreSelfApproval;
-  }
-
-  public void setIgnoreSelfApproval(boolean ignoreSelfApproval) {
-    this.ignoreSelfApproval = ignoreSelfApproval;
-  }
-
-  public void setRefPatterns(List<String> refPatterns) {
-    if (refPatterns != null && !refPatterns.isEmpty()) {
-      this.refPatterns =
-          refPatterns.stream().collect(collectingAndThen(toList(), Collections::unmodifiableList));
-    } else {
-      this.refPatterns = null;
-    }
-  }
-
-  public List<LabelValue> getValues() {
-    return values;
-  }
-
-  public void setValues(List<LabelValue> values) {
-    this.values = sortValues(values);
+    return psa.labelId().get().equalsIgnoreCase(getName());
   }
 
   public LabelValue getMin() {
-    if (values.isEmpty()) {
+    if (getValues().isEmpty()) {
       return null;
     }
-    return values.get(0);
+    return getValues().get(0);
   }
 
   public LabelValue getMax() {
-    if (values.isEmpty()) {
+    if (getValues().isEmpty()) {
       return null;
     }
-    return values.get(values.size() - 1);
-  }
-
-  public short getDefaultValue() {
-    return defaultValue;
-  }
-
-  public void setDefaultValue(short defaultValue) {
-    this.defaultValue = defaultValue;
-  }
-
-  public boolean isCopyAnyScore() {
-    return copyAnyScore;
-  }
-
-  public void setCopyAnyScore(boolean copyAnyScore) {
-    this.copyAnyScore = copyAnyScore;
-  }
-
-  public boolean isCopyMinScore() {
-    return copyMinScore;
-  }
-
-  public void setCopyMinScore(boolean copyMinScore) {
-    this.copyMinScore = copyMinScore;
-  }
-
-  public boolean isCopyMaxScore() {
-    return copyMaxScore;
-  }
-
-  public void setCopyMaxScore(boolean copyMaxScore) {
-    this.copyMaxScore = copyMaxScore;
-  }
-
-  public boolean isCopyAllScoresOnMergeFirstParentUpdate() {
-    return copyAllScoresOnMergeFirstParentUpdate;
-  }
-
-  public void setCopyAllScoresOnMergeFirstParentUpdate(
-      boolean copyAllScoresOnMergeFirstParentUpdate) {
-    this.copyAllScoresOnMergeFirstParentUpdate = copyAllScoresOnMergeFirstParentUpdate;
-  }
-
-  public boolean isCopyAllScoresOnTrivialRebase() {
-    return copyAllScoresOnTrivialRebase;
-  }
-
-  public void setCopyAllScoresOnTrivialRebase(boolean copyAllScoresOnTrivialRebase) {
-    this.copyAllScoresOnTrivialRebase = copyAllScoresOnTrivialRebase;
-  }
-
-  public boolean isCopyAllScoresIfNoCodeChange() {
-    return copyAllScoresIfNoCodeChange;
-  }
-
-  public void setCopyAllScoresIfNoCodeChange(boolean copyAllScoresIfNoCodeChange) {
-    this.copyAllScoresIfNoCodeChange = copyAllScoresIfNoCodeChange;
-  }
-
-  public boolean isCopyAllScoresIfNoChange() {
-    return copyAllScoresIfNoChange;
-  }
-
-  public void setCopyAllScoresIfNoChange(boolean copyAllScoresIfNoChange) {
-    this.copyAllScoresIfNoChange = copyAllScoresIfNoChange;
-  }
-
-  public ImmutableList<Short> getCopyValues() {
-    return copyValues;
-  }
-
-  public void setCopyValues(Collection<Short> copyValues) {
-    this.copyValues = copyValues.stream().sorted().collect(toImmutableList());
+    return getValues().get(getValues().size() - 1);
   }
 
   public boolean isMaxNegative(PatchSetApproval ca) {
-    return maxNegative == ca.value();
+    return getMaxNegative() == ca.value();
   }
 
   public boolean isMaxPositive(PatchSetApproval ca) {
-    return maxPositive == ca.value();
+    return getMaxPositive() == ca.value();
   }
 
   public LabelValue getValue(short value) {
-    return byValue.get(value);
+    return getByValue().get(value);
   }
 
   public LabelValue getValue(PatchSetApproval ca) {
-    return byValue.get(ca.value());
+    return getByValue().get(ca.value());
   }
 
   public LabelId getLabelId() {
-    return LabelId.create(name);
+    return LabelId.create(getName());
   }
 
   @Override
-  public String toString() {
-    StringBuilder sb = new StringBuilder(name).append('[');
+  public final String toString() {
+    StringBuilder sb = new StringBuilder(getName()).append('[');
     LabelValue min = getMin();
     LabelValue max = getMax();
     if (min != null && max != null) {
       sb.append(
-          new PermissionRange(Permission.forLabel(name), min.getValue(), max.getValue())
+          new PermissionRange(Permission.forLabel(getName()), min.getValue(), max.getValue())
               .toString()
               .trim());
     } else if (min != null) {
@@ -350,4 +213,84 @@
     sb.append(']');
     return sb.toString();
   }
+
+  public abstract Builder toBuilder();
+
+  @AutoValue.Builder
+  public abstract static class Builder {
+    public abstract Builder setName(String name);
+
+    public abstract Builder setFunction(LabelFunction function);
+
+    public abstract Builder setCanOverride(boolean canOverride);
+
+    public abstract Builder setAllowPostSubmit(boolean allowPostSubmit);
+
+    public abstract Builder setIgnoreSelfApproval(boolean ignoreSelfApproval);
+
+    public abstract Builder setRefPatterns(@Nullable ImmutableList<String> refPatterns);
+
+    public abstract Builder setValues(List<LabelValue> values);
+
+    public abstract Builder setDefaultValue(short defaultValue);
+
+    public abstract Builder setCopyAnyScore(boolean copyAnyScore);
+
+    public abstract Builder setCopyMinScore(boolean copyMinScore);
+
+    public abstract Builder setCopyMaxScore(boolean copyMaxScore);
+
+    public abstract Builder setCopyAllScoresOnMergeFirstParentUpdate(
+        boolean copyAllScoresOnMergeFirstParentUpdate);
+
+    public abstract Builder setCopyAllScoresOnTrivialRebase(boolean copyAllScoresOnTrivialRebase);
+
+    public abstract Builder setCopyAllScoresIfNoCodeChange(boolean copyAllScoresIfNoCodeChange);
+
+    public abstract Builder setCopyAllScoresIfNoChange(boolean copyAllScoresIfNoChange);
+
+    public abstract Builder setCopyValues(Collection<Short> copyValues);
+
+    public abstract Builder setMaxNegative(short maxNegative);
+
+    public abstract Builder setMaxPositive(short maxPositive);
+
+    public abstract ImmutableList<LabelValue> getValues();
+
+    protected abstract String getName();
+
+    protected abstract Builder setByValue(ImmutableMap<Short, LabelValue> byValue);
+
+    @Nullable
+    protected abstract ImmutableList<String> getRefPatterns();
+
+    protected abstract LabelType autoBuild();
+
+    public LabelType build() throws IllegalArgumentException {
+      setName(checkName(getName()));
+      if (getRefPatterns() == null || getRefPatterns().isEmpty()) {
+        // Empty to null
+        setRefPatterns(null);
+      }
+
+      List<LabelValue> valueList = sortValues(getValues());
+      setValues(valueList);
+      if (!valueList.isEmpty()) {
+        if (valueList.get(0).getValue() < 0) {
+          setMaxNegative(valueList.get(0).getValue());
+        }
+        if (valueList.get(valueList.size() - 1).getValue() > 0) {
+          setMaxPositive(valueList.get(valueList.size() - 1).getValue());
+        }
+      }
+
+      ImmutableMap.Builder<Short, LabelValue> byValue = ImmutableMap.builder();
+      for (LabelValue v : valueList) {
+        byValue.put(v.getValue(), v);
+      }
+      setByValue(byValue.build());
+
+      return autoBuild();
+    }
+  }
 }
diff --git a/java/com/google/gerrit/common/data/LabelValue.java b/java/com/google/gerrit/common/data/LabelValue.java
index c0ba781..ec16fb2 100644
--- a/java/com/google/gerrit/common/data/LabelValue.java
+++ b/java/com/google/gerrit/common/data/LabelValue.java
@@ -14,65 +14,42 @@
 
 package com.google.gerrit.common.data;
 
-import java.util.Objects;
+import com.google.auto.value.AutoValue;
 
-public class LabelValue {
+@AutoValue
+public abstract class LabelValue {
   public static String formatValue(short value) {
     if (value < 0) {
       return Short.toString(value);
     } else if (value == 0) {
       return " 0";
     } else {
-      return "+" + Short.toString(value);
+      return "+" + value;
     }
   }
 
-  protected short value;
-  protected String text;
+  public abstract short getValue();
 
-  public LabelValue(short value, String text) {
-    this.value = value;
-    this.text = text;
-  }
+  public abstract String getText();
 
-  protected LabelValue() {}
-
-  public short getValue() {
-    return value;
-  }
-
-  public String getText() {
-    return text;
+  public static LabelValue create(short value, String text) {
+    return new AutoValue_LabelValue(value, text);
   }
 
   public String formatValue() {
-    return formatValue(value);
+    return formatValue(getValue());
   }
 
   public String format() {
     StringBuilder sb = new StringBuilder(formatValue());
-    if (!text.isEmpty()) {
-      sb.append(' ').append(text);
+    if (!getText().isEmpty()) {
+      sb.append(' ').append(getText());
     }
     return sb.toString();
   }
 
   @Override
-  public boolean equals(Object o) {
-    if (!(o instanceof LabelValue)) {
-      return false;
-    }
-    LabelValue v = (LabelValue) o;
-    return value == v.value && Objects.equals(text, v.text);
-  }
-
-  @Override
-  public int hashCode() {
-    return Objects.hash(value, text);
-  }
-
-  @Override
-  public String toString() {
+  public final String toString() {
     return format();
   }
 }
diff --git a/java/com/google/gerrit/server/change/LabelsJson.java b/java/com/google/gerrit/server/change/LabelsJson.java
index 2db17d6..739e263 100644
--- a/java/com/google/gerrit/server/change/LabelsJson.java
+++ b/java/com/google/gerrit/server/change/LabelsJson.java
@@ -122,7 +122,7 @@
       if (rec.labels != null) {
         for (SubmitRecord.Label r : rec.labels) {
           LabelType type = labelTypes.byLabel(r.label);
-          if (type != null && (!isMerged || type.allowPostSubmit())) {
+          if (type != null && (!isMerged || type.isAllowPostSubmit())) {
             toCheck.put(type.getName(), type);
           }
         }
@@ -139,7 +139,7 @@
       }
       for (SubmitRecord.Label r : rec.labels) {
         LabelType type = labelTypes.byLabel(r.label);
-        if (type == null || (isMerged && !type.allowPostSubmit())) {
+        if (type == null || (isMerged && !type.isAllowPostSubmit())) {
           continue;
         }
 
diff --git a/java/com/google/gerrit/server/project/LabelDefinitionJson.java b/java/com/google/gerrit/server/project/LabelDefinitionJson.java
index 0452d0b..9ff079f 100644
--- a/java/com/google/gerrit/server/project/LabelDefinitionJson.java
+++ b/java/com/google/gerrit/server/project/LabelDefinitionJson.java
@@ -31,7 +31,7 @@
         labelType.getValues().stream().collect(toMap(LabelValue::formatValue, LabelValue::getText));
     label.defaultValue = labelType.getDefaultValue();
     label.branches = labelType.getRefPatterns() != null ? labelType.getRefPatterns() : null;
-    label.canOverride = toBoolean(labelType.canOverride());
+    label.canOverride = toBoolean(labelType.isCanOverride());
     label.copyAnyScore = toBoolean(labelType.isCopyAnyScore());
     label.copyMinScore = toBoolean(labelType.isCopyMinScore());
     label.copyMaxScore = toBoolean(labelType.isCopyMaxScore());
@@ -41,8 +41,8 @@
     label.copyAllScoresOnMergeFirstParentUpdate =
         toBoolean(labelType.isCopyAllScoresOnMergeFirstParentUpdate());
     label.copyValues = labelType.getCopyValues().isEmpty() ? null : labelType.getCopyValues();
-    label.allowPostSubmit = toBoolean(labelType.allowPostSubmit());
-    label.ignoreSelfApproval = toBoolean(labelType.ignoreSelfApproval());
+    label.allowPostSubmit = toBoolean(labelType.isAllowPostSubmit());
+    label.ignoreSelfApproval = toBoolean(labelType.isIgnoreSelfApproval());
     return label;
   }
 
diff --git a/java/com/google/gerrit/server/project/ProjectConfig.java b/java/com/google/gerrit/server/project/ProjectConfig.java
index 6b63ad2..3d4b024 100644
--- a/java/com/google/gerrit/server/project/ProjectConfig.java
+++ b/java/com/google/gerrit/server/project/ProjectConfig.java
@@ -15,6 +15,7 @@
 package com.google.gerrit.server.project;
 
 import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.collect.ImmutableList.toImmutableList;
 import static com.google.gerrit.common.data.Permission.isPermission;
 import static com.google.gerrit.entities.Project.DEFAULT_SUBMIT_TYPE;
@@ -495,6 +496,20 @@
     return labelSections;
   }
 
+  /** Adds or replaces the given {@link LabelType} in this config. */
+  public void upsertLabelType(LabelType labelType) {
+    labelSections.put(labelType.getName(), labelType);
+  }
+
+  /** Allows a mutation of an existing {@link LabelType}. */
+  public void updateLabelType(String name, Consumer<LabelType.Builder> update) {
+    LabelType labelType = labelSections.get(name);
+    checkState(labelType != null, "labelType must not be null");
+    LabelType.Builder builder = labelSections.get(name).toBuilder();
+    update.accept(builder);
+    upsertLabelType(builder.build());
+  }
+
   public Collection<StoredCommentLinkInfo> getCommentLinkSections() {
     return commentLinkSections.values();
   }
@@ -911,7 +926,7 @@
       throw new IllegalArgumentException("empty value");
     }
     String valueText = parts.size() > 1 ? parts.get(1) : "";
-    return new LabelValue(Shorts.checkedCast(PermissionRule.parseInt(parts.get(0))), valueText);
+    return LabelValue.create(Shorts.checkedCast(PermissionRule.parseInt(parts.get(0))), valueText);
   }
 
   private void loadLabelSections(Config rc) {
@@ -950,9 +965,9 @@
         }
       }
 
-      LabelType label;
+      LabelType.Builder label;
       try {
-        label = new LabelType(name, values);
+        label = LabelType.builder(name, values);
       } catch (IllegalArgumentException badName) {
         error(ValidationError.create(PROJECT_CONFIG, String.format("Invalid label \"%s\"", name)));
         continue;
@@ -1042,8 +1057,9 @@
       label.setCopyValues(copyValues);
       label.setCanOverride(
           rc.getBoolean(LABEL, name, KEY_CAN_OVERRIDE, LabelType.DEF_CAN_OVERRIDE));
-      label.setRefPatterns(getStringListOrNull(rc, LABEL, name, KEY_BRANCH));
-      labelSections.put(name, label);
+      List<String> refPatterns = getStringListOrNull(rc, LABEL, name, KEY_BRANCH);
+      label.setRefPatterns(refPatterns == null ? null : ImmutableList.copyOf(refPatterns));
+      labelSections.put(name, label.build());
     }
   }
 
@@ -1451,14 +1467,14 @@
           LABEL,
           name,
           KEY_ALLOW_POST_SUBMIT,
-          label.allowPostSubmit(),
+          label.isAllowPostSubmit(),
           LabelType.DEF_ALLOW_POST_SUBMIT);
       setBooleanConfigKey(
           rc,
           LABEL,
           name,
           KEY_IGNORE_SELF_APPROVAL,
-          label.ignoreSelfApproval(),
+          label.isIgnoreSelfApproval(),
           LabelType.DEF_IGNORE_SELF_APPROVAL);
       setBooleanConfigKey(
           rc,
@@ -1515,7 +1531,7 @@
           KEY_COPY_VALUE,
           label.getCopyValues().stream().map(LabelValue::formatValue).collect(toList()));
       setBooleanConfigKey(
-          rc, LABEL, name, KEY_CAN_OVERRIDE, label.canOverride(), LabelType.DEF_CAN_OVERRIDE);
+          rc, LABEL, name, KEY_CAN_OVERRIDE, label.isCanOverride(), LabelType.DEF_CAN_OVERRIDE);
       List<String> values = new ArrayList<>(label.getValues().size());
       for (LabelValue value : label.getValues()) {
         values.add(value.format().trim());
diff --git a/java/com/google/gerrit/server/project/ProjectState.java b/java/com/google/gerrit/server/project/ProjectState.java
index 3204472..6353103 100644
--- a/java/com/google/gerrit/server/project/ProjectState.java
+++ b/java/com/google/gerrit/server/project/ProjectState.java
@@ -402,7 +402,7 @@
       for (LabelType type : s.getConfig().getLabelSections().values()) {
         String lower = type.getName().toLowerCase();
         LabelType old = types.get(lower);
-        if (old == null || old.canOverride()) {
+        if (old == null || old.isCanOverride()) {
           types.put(lower, type);
         }
       }
diff --git a/java/com/google/gerrit/server/project/testing/TestLabels.java b/java/com/google/gerrit/server/project/testing/TestLabels.java
index 6c2ddde..2c0b23c 100644
--- a/java/com/google/gerrit/server/project/testing/TestLabels.java
+++ b/java/com/google/gerrit/server/project/testing/TestLabels.java
@@ -35,18 +35,23 @@
   }
 
   public static LabelType patchSetLock() {
-    LabelType label =
-        label("Patch-Set-Lock", value(1, "Patch Set Locked"), value(0, "Patch Set Unlocked"));
+    LabelType.Builder label =
+        labelBuilder(
+            "Patch-Set-Lock", value(1, "Patch Set Locked"), value(0, "Patch Set Unlocked"));
     label.setFunction(LabelFunction.PATCH_SET_LOCK);
-    return label;
+    return label.build();
   }
 
   public static LabelValue value(int value, String text) {
-    return new LabelValue((short) value, text);
+    return LabelValue.create((short) value, text);
   }
 
   public static LabelType label(String name, LabelValue... values) {
-    return new LabelType(name, Arrays.asList(values));
+    return labelBuilder(name, values).build();
+  }
+
+  public static LabelType.Builder labelBuilder(String name, LabelValue... values) {
+    return LabelType.builder(name, Arrays.asList(values));
   }
 
   private TestLabels() {}
diff --git a/java/com/google/gerrit/server/restapi/change/PostReview.java b/java/com/google/gerrit/server/restapi/change/PostReview.java
index 6edbdb0..85079e2 100644
--- a/java/com/google/gerrit/server/restapi/change/PostReview.java
+++ b/java/com/google/gerrit/server/restapi/change/PostReview.java
@@ -1319,7 +1319,7 @@
       for (PatchSetApproval psa : del) {
         LabelType lt = requireNonNull(labelTypes.byLabel(psa.label()));
         String normName = lt.getName();
-        if (!lt.allowPostSubmit()) {
+        if (!lt.isAllowPostSubmit()) {
           disallowed.add(normName);
         }
         Short prev = previous.get(normName);
@@ -1331,7 +1331,7 @@
       for (PatchSetApproval psa : ups) {
         LabelType lt = requireNonNull(labelTypes.byLabel(psa.label()));
         String normName = lt.getName();
-        if (!lt.allowPostSubmit()) {
+        if (!lt.isAllowPostSubmit()) {
           disallowed.add(normName);
         }
         Short prev = previous.get(normName);
diff --git a/java/com/google/gerrit/server/restapi/project/CreateLabel.java b/java/com/google/gerrit/server/restapi/project/CreateLabel.java
index a85ad39..1c19eb0 100644
--- a/java/com/google/gerrit/server/restapi/project/CreateLabel.java
+++ b/java/com/google/gerrit/server/restapi/project/CreateLabel.java
@@ -134,15 +134,15 @@
       throw new BadRequestException("values are required");
     }
 
-    List<LabelValue> values = LabelDefinitionInputParser.parseValues(input.values);
-
-    LabelType labelType;
     try {
-      labelType = new LabelType(label, values);
+      LabelType.checkName(label);
     } catch (IllegalArgumentException e) {
       throw new BadRequestException("invalid name: " + label, e);
     }
 
+    List<LabelValue> values = LabelDefinitionInputParser.parseValues(input.values);
+    LabelType.Builder labelType = LabelType.builder(LabelType.checkName(label), values);
+
     if (input.function != null && !input.function.trim().isEmpty()) {
       labelType.setFunction(LabelDefinitionInputParser.parseFunction(input.function));
     } else {
@@ -203,8 +203,9 @@
       labelType.setIgnoreSelfApproval(input.ignoreSelfApproval);
     }
 
-    config.getLabelSections().put(labelType.getName(), labelType);
+    LabelType lt = labelType.build();
+    config.upsertLabelType(lt);
 
-    return labelType;
+    return lt;
   }
 }
diff --git a/java/com/google/gerrit/server/restapi/project/LabelDefinitionInputParser.java b/java/com/google/gerrit/server/restapi/project/LabelDefinitionInputParser.java
index 1e288f4..ccc216d 100644
--- a/java/com/google/gerrit/server/restapi/project/LabelDefinitionInputParser.java
+++ b/java/com/google/gerrit/server/restapi/project/LabelDefinitionInputParser.java
@@ -14,6 +14,7 @@
 
 package com.google.gerrit.server.restapi.project;
 
+import com.google.common.collect.ImmutableList;
 import com.google.common.primitives.Shorts;
 import com.google.gerrit.common.data.LabelFunction;
 import com.google.gerrit.common.data.LabelType;
@@ -56,21 +57,22 @@
       if (valueDescription.isEmpty()) {
         throw new BadRequestException("description for value '" + e.getKey() + "' cannot be empty");
       }
-      valueList.add(new LabelValue(value, valueDescription));
+      valueList.add(LabelValue.create(value, valueDescription));
     }
     return valueList;
   }
 
-  public static short parseDefaultValue(LabelType labelType, short defaultValue)
+  public static short parseDefaultValue(LabelType.Builder labelType, short defaultValue)
       throws BadRequestException {
-    if (labelType.getValue(defaultValue) == null) {
+    if (!labelType.getValues().stream().anyMatch(v -> v.getValue() == defaultValue)) {
       throw new BadRequestException("invalid default value: " + defaultValue);
     }
     return defaultValue;
   }
 
-  public static List<String> parseBranches(List<String> branches) throws BadRequestException {
-    List<String> validBranches = new ArrayList<>();
+  public static ImmutableList<String> parseBranches(List<String> branches)
+      throws BadRequestException {
+    ImmutableList.Builder<String> validBranches = ImmutableList.builder();
     for (String branch : branches) {
       String newBranch = branch.trim();
       if (newBranch.isEmpty()) {
@@ -86,7 +88,7 @@
       }
       validBranches.add(newBranch);
     }
-    return validBranches;
+    return validBranches.build();
   }
 
   private LabelDefinitionInputParser() {}
diff --git a/java/com/google/gerrit/server/restapi/project/SetLabel.java b/java/com/google/gerrit/server/restapi/project/SetLabel.java
index 0a35865..ade274a 100644
--- a/java/com/google/gerrit/server/restapi/project/SetLabel.java
+++ b/java/com/google/gerrit/server/restapi/project/SetLabel.java
@@ -88,6 +88,9 @@
         } else {
           md.setMessage("Update label");
         }
+        String newName = Strings.nullToEmpty(input.name).trim();
+        labelType =
+            config.getLabelSections().get(newName.isEmpty() ? labelType.getName() : newName);
 
         config.commit(md);
         projectCache.evict(rsrc.getProject().getProjectState().getProject());
@@ -109,8 +112,7 @@
   public boolean updateLabel(ProjectConfig config, LabelType labelType, LabelDefinitionInput input)
       throws BadRequestException, ResourceConflictException {
     boolean dirty = false;
-
-    config.getLabelSections().remove(labelType.getName());
+    LabelType.Builder labelTypeBuilder = labelType.toBuilder();
 
     if (input.name != null) {
       String newName = input.name.trim();
@@ -130,10 +132,12 @@
         }
 
         try {
-          labelType.setName(newName);
+          LabelType.checkName(newName);
         } catch (IllegalArgumentException e) {
           throw new BadRequestException("invalid name: " + input.name, e);
         }
+
+        labelTypeBuilder.setName(newName);
         dirty = true;
       }
     }
@@ -142,7 +146,7 @@
       if (input.function.trim().isEmpty()) {
         throw new BadRequestException("function cannot be empty");
       }
-      labelType.setFunction(LabelDefinitionInputParser.parseFunction(input.function));
+      labelTypeBuilder.setFunction(LabelDefinitionInputParser.parseFunction(input.function));
       dirty = true;
     }
 
@@ -150,77 +154,79 @@
       if (input.values.isEmpty()) {
         throw new BadRequestException("values cannot be empty");
       }
-      labelType.setValues(LabelDefinitionInputParser.parseValues(input.values));
+      labelTypeBuilder.setValues(LabelDefinitionInputParser.parseValues(input.values));
       dirty = true;
     }
 
     if (input.defaultValue != null) {
-      labelType.setDefaultValue(
-          LabelDefinitionInputParser.parseDefaultValue(labelType, input.defaultValue));
+      labelTypeBuilder.setDefaultValue(
+          LabelDefinitionInputParser.parseDefaultValue(labelTypeBuilder, input.defaultValue));
       dirty = true;
     }
 
     if (input.branches != null) {
-      labelType.setRefPatterns(LabelDefinitionInputParser.parseBranches(input.branches));
+      labelTypeBuilder.setRefPatterns(LabelDefinitionInputParser.parseBranches(input.branches));
       dirty = true;
     }
 
     if (input.canOverride != null) {
-      labelType.setCanOverride(input.canOverride);
+      labelTypeBuilder.setCanOverride(input.canOverride);
       dirty = true;
     }
 
     if (input.copyAnyScore != null) {
-      labelType.setCopyAnyScore(input.copyAnyScore);
+      labelTypeBuilder.setCopyAnyScore(input.copyAnyScore);
       dirty = true;
     }
 
     if (input.copyMinScore != null) {
-      labelType.setCopyMinScore(input.copyMinScore);
+      labelTypeBuilder.setCopyMinScore(input.copyMinScore);
       dirty = true;
     }
 
     if (input.copyMaxScore != null) {
-      labelType.setCopyMaxScore(input.copyMaxScore);
+      labelTypeBuilder.setCopyMaxScore(input.copyMaxScore);
       dirty = true;
     }
 
     if (input.copyAllScoresIfNoChange != null) {
-      labelType.setCopyAllScoresIfNoChange(input.copyAllScoresIfNoChange);
+      labelTypeBuilder.setCopyAllScoresIfNoChange(input.copyAllScoresIfNoChange);
+      dirty = true;
     }
 
     if (input.copyAllScoresIfNoCodeChange != null) {
-      labelType.setCopyAllScoresIfNoCodeChange(input.copyAllScoresIfNoCodeChange);
+      labelTypeBuilder.setCopyAllScoresIfNoCodeChange(input.copyAllScoresIfNoCodeChange);
       dirty = true;
     }
 
     if (input.copyAllScoresOnTrivialRebase != null) {
-      labelType.setCopyAllScoresOnTrivialRebase(input.copyAllScoresOnTrivialRebase);
+      labelTypeBuilder.setCopyAllScoresOnTrivialRebase(input.copyAllScoresOnTrivialRebase);
       dirty = true;
     }
 
     if (input.copyAllScoresOnMergeFirstParentUpdate != null) {
-      labelType.setCopyAllScoresOnMergeFirstParentUpdate(
+      labelTypeBuilder.setCopyAllScoresOnMergeFirstParentUpdate(
           input.copyAllScoresOnMergeFirstParentUpdate);
       dirty = true;
     }
 
     if (input.copyValues != null) {
-      labelType.setCopyValues(input.copyValues);
+      labelTypeBuilder.setCopyValues(input.copyValues);
       dirty = true;
     }
 
     if (input.allowPostSubmit != null) {
-      labelType.setAllowPostSubmit(input.allowPostSubmit);
+      labelTypeBuilder.setAllowPostSubmit(input.allowPostSubmit);
       dirty = true;
     }
 
     if (input.ignoreSelfApproval != null) {
-      labelType.setIgnoreSelfApproval(input.ignoreSelfApproval);
+      labelTypeBuilder.setIgnoreSelfApproval(input.ignoreSelfApproval);
       dirty = true;
     }
 
-    config.getLabelSections().put(labelType.getName(), labelType);
+    config.getLabelSections().remove(labelType.getName());
+    config.upsertLabelType(labelTypeBuilder.build());
 
     return dirty;
   }
diff --git a/java/com/google/gerrit/server/rules/IgnoreSelfApprovalRule.java b/java/com/google/gerrit/server/rules/IgnoreSelfApprovalRule.java
index 54915fb..132747d 100644
--- a/java/com/google/gerrit/server/rules/IgnoreSelfApprovalRule.java
+++ b/java/com/google/gerrit/server/rules/IgnoreSelfApprovalRule.java
@@ -66,7 +66,8 @@
       return ruleError(E_UNABLE_TO_FETCH_LABELS);
     }
 
-    boolean shouldIgnoreSelfApproval = labelTypes.stream().anyMatch(LabelType::ignoreSelfApproval);
+    boolean shouldIgnoreSelfApproval =
+        labelTypes.stream().anyMatch(LabelType::isIgnoreSelfApproval);
     if (!shouldIgnoreSelfApproval) {
       // Shortcut to avoid further processing if no label should ignore uploader approvals
       return Optional.empty();
@@ -86,7 +87,7 @@
     submitRecord.requirements = new ArrayList<>();
 
     for (LabelType t : labelTypes) {
-      if (!t.ignoreSelfApproval()) {
+      if (!t.isIgnoreSelfApproval()) {
         // The default rules are enough in this case.
         continue;
       }
diff --git a/java/com/google/gerrit/server/schema/AllProjectsCreator.java b/java/com/google/gerrit/server/schema/AllProjectsCreator.java
index af5e8e0..018a96a 100644
--- a/java/com/google/gerrit/server/schema/AllProjectsCreator.java
+++ b/java/com/google/gerrit/server/schema/AllProjectsCreator.java
@@ -124,11 +124,7 @@
           });
 
       // init labels.
-      input
-          .codeReviewLabel()
-          .ifPresent(
-              codeReviewLabel ->
-                  config.getLabelSections().put(codeReviewLabel.getName(), codeReviewLabel));
+      input.codeReviewLabel().ifPresent(codeReviewLabel -> config.upsertLabelType(codeReviewLabel));
 
       if (input.initDefaultAcls()) {
         // init access sections.
diff --git a/java/com/google/gerrit/server/schema/AllProjectsInput.java b/java/com/google/gerrit/server/schema/AllProjectsInput.java
index 6e11a5d..c91695f 100644
--- a/java/com/google/gerrit/server/schema/AllProjectsInput.java
+++ b/java/com/google/gerrit/server/schema/AllProjectsInput.java
@@ -46,18 +46,17 @@
 
   @UsedAt(UsedAt.Project.GOOGLE)
   public static LabelType getDefaultCodeReviewLabel() {
-    LabelType type =
-        new LabelType(
+    return LabelType.builder(
             "Code-Review",
             ImmutableList.of(
-                new LabelValue((short) 2, "Looks good to me, approved"),
-                new LabelValue((short) 1, "Looks good to me, but someone else must approve"),
-                new LabelValue((short) 0, "No score"),
-                new LabelValue((short) -1, "I would prefer this is not merged as is"),
-                new LabelValue((short) -2, "This shall not be merged")));
-    type.setCopyMinScore(true);
-    type.setCopyAllScoresOnTrivialRebase(true);
-    return type;
+                LabelValue.create((short) 2, "Looks good to me, approved"),
+                LabelValue.create((short) 1, "Looks good to me, but someone else must approve"),
+                LabelValue.create((short) 0, "No score"),
+                LabelValue.create((short) -1, "I would prefer this is not merged as is"),
+                LabelValue.create((short) -2, "This shall not be merged")))
+        .setCopyMinScore(true)
+        .setCopyAllScoresOnTrivialRebase(true)
+        .build();
   }
 
   /** The administrator group which gets default permissions granted. */
diff --git a/java/com/google/gerrit/server/schema/AllUsersCreator.java b/java/com/google/gerrit/server/schema/AllUsersCreator.java
index a471ab6..10d7070 100644
--- a/java/com/google/gerrit/server/schema/AllUsersCreator.java
+++ b/java/com/google/gerrit/server/schema/AllUsersCreator.java
@@ -118,7 +118,7 @@
               RefNames.REFS_USERS + "${" + RefPattern.USERID_SHARDED + "}", true);
 
       // Initialize "Code-Review" label.
-      config.getLabelSections().put(codeReviewLabel.getName(), codeReviewLabel);
+      config.upsertLabelType(codeReviewLabel);
 
       grant(config, users, Permission.READ, false, true, registered);
       grant(config, users, Permission.PUSH, false, true, registered);
diff --git a/javatests/com/google/gerrit/acceptance/api/change/ChangeIT.java b/javatests/com/google/gerrit/acceptance/api/change/ChangeIT.java
index 744035e..17b608e 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/ChangeIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/ChangeIT.java
@@ -2231,7 +2231,7 @@
     LabelType verified =
         label("Verified", value(1, "Passes"), value(0, "No score"), value(-1, "Failed"));
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(verified.getName(), verified);
+      u.getConfig().upsertLabelType(verified);
       u.save();
     }
     projectOperations
@@ -2518,7 +2518,7 @@
         label("Verified", value(1, "Passes"), value(0, "No score"), value(-1, "Failed"));
     String heads = "refs/heads/*";
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(verified.getName(), verified);
+      u.getConfig().upsertLabelType(verified);
       u.save();
     }
     projectOperations
@@ -2863,9 +2863,9 @@
     LabelType custom2 =
         label("Custom2", value(1, "Positive"), value(0, "No score"), value(-1, "Negative"));
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(verified.getName(), verified);
-      u.getConfig().getLabelSections().put(custom1.getName(), custom1);
-      u.getConfig().getLabelSections().put(custom2.getName(), custom2);
+      u.getConfig().upsertLabelType(verified);
+      u.getConfig().upsertLabelType(custom1);
+      u.getConfig().upsertLabelType(custom2);
       u.save();
     }
     projectOperations
@@ -3603,7 +3603,7 @@
     String heads = RefNames.REFS_HEADS + "*";
 
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(verified.getName(), verified);
+      u.getConfig().upsertLabelType(verified);
       u.save();
     }
     projectOperations
@@ -3671,7 +3671,7 @@
 
     // add new label and assert that it's returned for existing changes
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(verified.getName(), verified);
+      u.getConfig().upsertLabelType(verified);
       u.save();
     }
     projectOperations
diff --git a/javatests/com/google/gerrit/acceptance/api/change/StickyApprovalsIT.java b/javatests/com/google/gerrit/acceptance/api/change/StickyApprovalsIT.java
index 923b66f..3d8a034 100644
--- a/javatests/com/google/gerrit/acceptance/api/change/StickyApprovalsIT.java
+++ b/javatests/com/google/gerrit/acceptance/api/change/StickyApprovalsIT.java
@@ -26,7 +26,7 @@
 import static com.google.gerrit.extensions.client.ListChangesOption.CURRENT_REVISION;
 import static com.google.gerrit.extensions.client.ListChangesOption.DETAILED_LABELS;
 import static com.google.gerrit.server.group.SystemGroupBackend.REGISTERED_USERS;
-import static com.google.gerrit.server.project.testing.TestLabels.label;
+import static com.google.gerrit.server.project.testing.TestLabels.labelBuilder;
 import static com.google.gerrit.server.project.testing.TestLabels.value;
 import static org.eclipse.jgit.lib.Constants.HEAD;
 
@@ -78,8 +78,8 @@
     try (ProjectConfigUpdate u = updateProject(project)) {
       // Overwrite "Code-Review" label that is inherited from All-Projects.
       // This way changes to the "Code Review" label don't affect other tests.
-      LabelType codeReview =
-          label(
+      LabelType.Builder codeReview =
+          labelBuilder(
               "Code-Review",
               value(2, "Looks good to me, approved"),
               value(1, "Looks good to me, but someone else must approve"),
@@ -87,12 +87,12 @@
               value(-1, "I would prefer that you didn't submit this"),
               value(-2, "Do not submit"));
       codeReview.setCopyAllScoresIfNoChange(false);
-      u.getConfig().getLabelSections().put(codeReview.getName(), codeReview);
+      u.getConfig().upsertLabelType(codeReview.build());
 
-      LabelType verified =
-          label("Verified", value(1, "Passes"), value(0, "No score"), value(-1, "Failed"));
+      LabelType.Builder verified =
+          labelBuilder("Verified", value(1, "Passes"), value(0, "No score"), value(-1, "Failed"));
       verified.setCopyAllScoresIfNoChange(false);
-      u.getConfig().getLabelSections().put(verified.getName(), verified);
+      u.getConfig().upsertLabelType(verified.build());
 
       u.save();
     }
@@ -121,7 +121,7 @@
   @Test
   public void stickyOnAnyScore() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyAnyScore(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyAnyScore(true));
       u.save();
     }
 
@@ -143,7 +143,7 @@
   @Test
   public void stickyOnMinScore() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyMinScore(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyMinScore(true));
       u.save();
     }
 
@@ -165,7 +165,7 @@
   @Test
   public void stickyOnMaxScore() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyMaxScore(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyMaxScore(true));
       u.save();
     }
 
@@ -190,9 +190,8 @@
 
     try (ProjectConfigUpdate u = updateProject(project)) {
       u.getConfig()
-          .getLabelSections()
-          .get("Code-Review")
-          .setCopyValues(ImmutableList.of((short) -1, (short) 1));
+          .updateLabelType(
+              "Code-Review", b -> b.setCopyValues(ImmutableList.of((short) -1, (short) 1)));
       u.save();
     }
 
@@ -216,7 +215,7 @@
   @Test
   public void stickyOnTrivialRebase() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyAllScoresOnTrivialRebase(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyAllScoresOnTrivialRebase(true));
       u.save();
     }
 
@@ -262,7 +261,7 @@
   @Test
   public void stickyOnNoCodeChange() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Verified").setCopyAllScoresIfNoCodeChange(true);
+      u.getConfig().updateLabelType("Verified", b -> b.setCopyAllScoresIfNoCodeChange(true));
       u.save();
     }
 
@@ -287,9 +286,7 @@
   public void stickyOnMergeFirstParentUpdate() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
       u.getConfig()
-          .getLabelSections()
-          .get("Code-Review")
-          .setCopyAllScoresOnMergeFirstParentUpdate(true);
+          .updateLabelType("Code-Review", b -> b.setCopyAllScoresOnMergeFirstParentUpdate(true));
       u.save();
     }
 
@@ -313,7 +310,7 @@
   @Test
   public void notStickyWithCopyOnNoChangeWhenSecondParentIsUpdated() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyAllScoresIfNoChange(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyAllScoresIfNoChange(true));
       u.save();
     }
 
@@ -330,8 +327,8 @@
   @Test
   public void removedVotesNotSticky() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyAllScoresOnTrivialRebase(true);
-      u.getConfig().getLabelSections().get("Verified").setCopyAllScoresIfNoCodeChange(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyAllScoresOnTrivialRebase(true));
+      u.getConfig().updateLabelType("Verified", b -> b.setCopyAllScoresIfNoCodeChange(true));
       u.save();
     }
 
@@ -360,8 +357,8 @@
   @Test
   public void stickyAcrossMultiplePatchSets() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyMaxScore(true);
-      u.getConfig().getLabelSections().get("Verified").setCopyAllScoresIfNoCodeChange(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyMaxScore(true));
+      u.getConfig().updateLabelType("Verified", b -> b.setCopyAllScoresIfNoCodeChange(true));
       u.save();
     }
 
@@ -386,8 +383,8 @@
     // change kind against all prior patch sets. This is a regression that made Gerrit do expensive
     // work in O(num-patch-sets). This test ensures that we aren't regressing.
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyMaxScore(true);
-      u.getConfig().getLabelSections().get("Verified").setCopyAllScoresIfNoCodeChange(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyMaxScore(true));
+      u.getConfig().updateLabelType("Verified", b -> b.setCopyAllScoresIfNoCodeChange(true));
       u.save();
     }
 
@@ -418,8 +415,8 @@
   @Test
   public void copyMinMaxAcrossMultiplePatchSets() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get("Code-Review").setCopyMaxScore(true);
-      u.getConfig().getLabelSections().get("Code-Review").setCopyMinScore(true);
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyMaxScore(true));
+      u.getConfig().updateLabelType("Code-Review", b -> b.setCopyMinScore(true));
       u.save();
     }
 
@@ -459,7 +456,7 @@
   public void deleteStickyVote() throws Exception {
     String label = "Code-Review";
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().get(label).setCopyMaxScore(true);
+      u.getConfig().updateLabelType(label, b -> b.setCopyMaxScore(true));
       u.save();
     }
 
diff --git a/javatests/com/google/gerrit/acceptance/edit/ChangeEditIT.java b/javatests/com/google/gerrit/acceptance/edit/ChangeEditIT.java
index f0bb201..d361247 100644
--- a/javatests/com/google/gerrit/acceptance/edit/ChangeEditIT.java
+++ b/javatests/com/google/gerrit/acceptance/edit/ChangeEditIT.java
@@ -772,8 +772,9 @@
     String cr = "Code-Review";
     try (ProjectConfigUpdate u = updateProject(project)) {
       LabelType codeReview = TestLabels.codeReview();
-      codeReview.setCopyAllScoresIfNoCodeChange(true);
-      u.getConfig().getLabelSections().put(cr, codeReview);
+      u.getConfig().upsertLabelType(codeReview);
+      u.getConfig()
+          .updateLabelType(codeReview.getName(), lt -> lt.setCopyAllScoresIfNoCodeChange(true));
       u.save();
     }
 
diff --git a/javatests/com/google/gerrit/acceptance/git/AbstractPushForReview.java b/javatests/com/google/gerrit/acceptance/git/AbstractPushForReview.java
index 952a5f0..b01b195 100644
--- a/javatests/com/google/gerrit/acceptance/git/AbstractPushForReview.java
+++ b/javatests/com/google/gerrit/acceptance/git/AbstractPushForReview.java
@@ -161,7 +161,7 @@
   public void setUpPatchSetLock() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
       patchSetLock = TestLabels.patchSetLock();
-      u.getConfig().getLabelSections().put(patchSetLock.getName(), patchSetLock);
+      u.getConfig().upsertLabelType(patchSetLock);
       u.save();
     }
     projectOperations
@@ -1200,7 +1200,7 @@
         label("Custom-Label", value(1, "Positive"), value(0, "No score"), value(-1, "Negative"));
     String heads = "refs/heads/*";
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(Q.getName(), Q);
+      u.getConfig().upsertLabelType(Q);
       u.save();
     }
     projectOperations
@@ -1867,9 +1867,8 @@
   @Test
   public void pushNewPatchsetOverridingStickyLabel() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType codeReview = TestLabels.codeReview();
-      codeReview.setCopyMaxScore(true);
-      u.getConfig().getLabelSections().put(codeReview.getName(), codeReview);
+      LabelType codeReview = TestLabels.codeReview().toBuilder().setCopyMaxScore(true).build();
+      u.getConfig().upsertLabelType(codeReview);
       u.save();
     }
 
diff --git a/javatests/com/google/gerrit/acceptance/rest/account/ImpersonationIT.java b/javatests/com/google/gerrit/acceptance/rest/account/ImpersonationIT.java
index 840853c..00c7fb8 100644
--- a/javatests/com/google/gerrit/acceptance/rest/account/ImpersonationIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/account/ImpersonationIT.java
@@ -174,7 +174,7 @@
   public void voteOnBehalfOfLabelNotPermitted() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
       LabelType verified = TestLabels.verified();
-      u.getConfig().getLabelSections().put(verified.getName(), verified);
+      u.getConfig().upsertLabelType(verified);
       u.save();
     }
 
diff --git a/javatests/com/google/gerrit/acceptance/rest/change/MoveChangeIT.java b/javatests/com/google/gerrit/acceptance/rest/change/MoveChangeIT.java
index 37b1713..542085c 100644
--- a/javatests/com/google/gerrit/acceptance/rest/change/MoveChangeIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/change/MoveChangeIT.java
@@ -245,7 +245,7 @@
 
     LabelType patchSetLock = TestLabels.patchSetLock();
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(patchSetLock.getName(), patchSetLock);
+      u.getConfig().upsertLabelType(patchSetLock);
       u.save();
     }
     projectOperations
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/GetLabelIT.java b/javatests/com/google/gerrit/acceptance/rest/project/GetLabelIT.java
index 940fae5..3e35f04 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/GetLabelIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/project/GetLabelIT.java
@@ -22,7 +22,6 @@
 import com.google.gerrit.acceptance.NoHttpd;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.LabelFunction;
-import com.google.gerrit.common.data.LabelType;
 import com.google.gerrit.extensions.common.LabelDefinitionInfo;
 import com.google.gerrit.extensions.restapi.AuthException;
 import com.google.gerrit.extensions.restapi.ResourceNotFoundException;
@@ -75,9 +74,7 @@
 
     // set default value
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setDefaultValue((short) 1);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", labelType -> labelType.setDefaultValue((short) 1));
       u.save();
     }
 
@@ -100,11 +97,14 @@
 
     // unset rules which are enabled by default
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCanOverride(false);
-      labelType.setCopyAllScoresIfNoChange(false);
-      labelType.setAllowPostSubmit(false);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig()
+          .updateLabelType(
+              "foo",
+              labelType -> {
+                labelType.setCanOverride(false);
+                labelType.setCopyAllScoresIfNoChange(false);
+                labelType.setAllowPostSubmit(false);
+              });
       u.save();
     }
 
@@ -128,16 +128,19 @@
 
     // set rules which are not enabled by default
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyAnyScore(true);
-      labelType.setCopyMinScore(true);
-      labelType.setCopyMaxScore(true);
-      labelType.setCopyAllScoresIfNoCodeChange(true);
-      labelType.setCopyAllScoresOnTrivialRebase(true);
-      labelType.setCopyAllScoresOnMergeFirstParentUpdate(true);
-      labelType.setCopyValues(ImmutableList.of((short) -1, (short) 1));
-      labelType.setIgnoreSelfApproval(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig()
+          .updateLabelType(
+              "foo",
+              labelType -> {
+                labelType.setCopyAnyScore(true);
+                labelType.setCopyMinScore(true);
+                labelType.setCopyMaxScore(true);
+                labelType.setCopyAllScoresIfNoCodeChange(true);
+                labelType.setCopyAllScoresOnTrivialRebase(true);
+                labelType.setCopyAllScoresOnMergeFirstParentUpdate(true);
+                labelType.setCopyValues(ImmutableList.of((short) -1, (short) 1));
+                labelType.setIgnoreSelfApproval(true);
+              });
       u.save();
     }
 
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/ListLabelsIT.java b/javatests/com/google/gerrit/acceptance/rest/project/ListLabelsIT.java
index ef08079..33a0654 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/ListLabelsIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/project/ListLabelsIT.java
@@ -27,7 +27,6 @@
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.LabelFunction;
-import com.google.gerrit.common.data.LabelType;
 import com.google.gerrit.common.data.Permission;
 import com.google.gerrit.entities.Project;
 import com.google.gerrit.entities.RefNames;
@@ -88,9 +87,7 @@
 
     // set default value
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setDefaultValue((short) 1);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", labelType -> labelType.setDefaultValue((short) 1));
       u.save();
     }
 
@@ -119,11 +116,14 @@
 
     // unset rules which are enabled by default
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCanOverride(false);
-      labelType.setCopyAllScoresIfNoChange(false);
-      labelType.setAllowPostSubmit(false);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig()
+          .updateLabelType(
+              "foo",
+              labelType -> {
+                labelType.setCanOverride(false);
+                labelType.setCopyAllScoresIfNoChange(false);
+                labelType.setAllowPostSubmit(false);
+              });
       u.save();
     }
 
@@ -150,16 +150,19 @@
 
     // set rules which are not enabled by default
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyAnyScore(true);
-      labelType.setCopyMinScore(true);
-      labelType.setCopyMaxScore(true);
-      labelType.setCopyAllScoresIfNoCodeChange(true);
-      labelType.setCopyAllScoresOnTrivialRebase(true);
-      labelType.setCopyAllScoresOnMergeFirstParentUpdate(true);
-      labelType.setCopyValues(ImmutableList.of((short) -1, (short) 1));
-      labelType.setIgnoreSelfApproval(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig()
+          .updateLabelType(
+              "foo",
+              labelType -> {
+                labelType.setCopyAnyScore(true);
+                labelType.setCopyMinScore(true);
+                labelType.setCopyMaxScore(true);
+                labelType.setCopyAllScoresIfNoCodeChange(true);
+                labelType.setCopyAllScoresOnTrivialRebase(true);
+                labelType.setCopyAllScoresOnMergeFirstParentUpdate(true);
+                labelType.setCopyValues(ImmutableList.of((short) -1, (short) 1));
+                labelType.setIgnoreSelfApproval(true);
+              });
       u.save();
     }
 
diff --git a/javatests/com/google/gerrit/acceptance/rest/project/SetLabelIT.java b/javatests/com/google/gerrit/acceptance/rest/project/SetLabelIT.java
index b08c72b..a1817d9 100644
--- a/javatests/com/google/gerrit/acceptance/rest/project/SetLabelIT.java
+++ b/javatests/com/google/gerrit/acceptance/rest/project/SetLabelIT.java
@@ -26,7 +26,6 @@
 import com.google.gerrit.acceptance.testsuite.project.ProjectOperations;
 import com.google.gerrit.acceptance.testsuite.request.RequestScopeOperations;
 import com.google.gerrit.common.data.LabelFunction;
-import com.google.gerrit.common.data.LabelType;
 import com.google.gerrit.common.data.Permission;
 import com.google.gerrit.entities.RefNames;
 import com.google.gerrit.extensions.common.LabelDefinitionInfo;
@@ -450,9 +449,7 @@
   public void setCanOverride() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCanOverride(false);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setCanOverride(false));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().canOverride).isNull();
@@ -501,9 +498,7 @@
   public void unsetCopyAnyScore() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyAnyScore(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setCopyAnyScore(true));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().copyAnyScore).isTrue();
@@ -537,9 +532,7 @@
   public void unsetCopyMinScore() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyMinScore(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setCopyMinScore(true));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().copyMinScore).isTrue();
@@ -573,9 +566,7 @@
   public void unsetCopyMaxScore() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyMaxScore(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setCopyMaxScore(true));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().copyMaxScore).isTrue();
@@ -594,9 +585,7 @@
   public void setCopyAllScoresIfNoChange() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyAllScoresIfNoChange(false);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setCopyAllScoresIfNoChange(false));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoChange)
@@ -651,9 +640,7 @@
   public void unsetCopyAllScoresIfNoCodeChange() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyAllScoresIfNoCodeChange(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setCopyAllScoresIfNoCodeChange(true));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresIfNoCodeChange)
@@ -691,9 +678,7 @@
   public void unsetCopyAllScoresOnTrivialRebase() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyAllScoresOnTrivialRebase(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setCopyAllScoresOnTrivialRebase(true));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().copyAllScoresOnTrivialRebase)
@@ -741,9 +726,7 @@
   public void unsetCopyAllScoresOnMergeFirstParentUpdate() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyAllScoresOnMergeFirstParentUpdate(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setCopyAllScoresOnMergeFirstParentUpdate(true));
       u.save();
     }
     assertThat(
@@ -791,9 +774,8 @@
   public void unsetCopyValues() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setCopyValues(ImmutableList.of((short) -1, (short) 1));
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig()
+          .updateLabelType("foo", lt -> lt.setCopyValues(ImmutableList.of((short) -1, (short) 1)));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().copyValues).isNotEmpty();
@@ -812,9 +794,7 @@
   public void setAllowPostSubmit() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setAllowPostSubmit(false);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setAllowPostSubmit(false));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().allowPostSubmit).isNull();
@@ -863,9 +843,7 @@
   public void unsetIgnoreSelfApproval() throws Exception {
     configLabel("foo", LabelFunction.NO_OP);
     try (ProjectConfigUpdate u = updateProject(project)) {
-      LabelType labelType = u.getConfig().getLabelSections().get("foo");
-      labelType.setIgnoreSelfApproval(true);
-      u.getConfig().getLabelSections().put(labelType.getName(), labelType);
+      u.getConfig().updateLabelType("foo", lt -> lt.setIgnoreSelfApproval(true));
       u.save();
     }
     assertThat(gApi.projects().name(project.get()).label("foo").get().ignoreSelfApproval).isTrue();
diff --git a/javatests/com/google/gerrit/acceptance/server/event/CommentAddedEventIT.java b/javatests/com/google/gerrit/acceptance/server/event/CommentAddedEventIT.java
index 8469fff..17eb534 100644
--- a/javatests/com/google/gerrit/acceptance/server/event/CommentAddedEventIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/event/CommentAddedEventIT.java
@@ -61,8 +61,8 @@
 
   private void saveLabelConfig() throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(label.getName(), label);
-      u.getConfig().getLabelSections().put(pLabel.getName(), pLabel);
+      u.getConfig().upsertLabelType(label);
+      u.getConfig().upsertLabelType(pLabel);
       u.save();
     }
   }
diff --git a/javatests/com/google/gerrit/acceptance/server/project/CustomLabelIT.java b/javatests/com/google/gerrit/acceptance/server/project/CustomLabelIT.java
index 1d5204b..813a715 100644
--- a/javatests/com/google/gerrit/acceptance/server/project/CustomLabelIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/project/CustomLabelIT.java
@@ -32,6 +32,7 @@
 import static com.google.gerrit.server.project.testing.TestLabels.value;
 import static com.google.gerrit.testing.GerritJUnit.assertThrows;
 
+import com.google.common.collect.ImmutableList;
 import com.google.gerrit.acceptance.AbstractDaemonTest;
 import com.google.gerrit.acceptance.ExtensionRegistry;
 import com.google.gerrit.acceptance.ExtensionRegistry.Registration;
@@ -48,39 +49,38 @@
 import com.google.gerrit.extensions.restapi.ResourceConflictException;
 import com.google.gerrit.server.project.ProjectConfig;
 import com.google.inject.Inject;
-import java.util.Arrays;
 import org.junit.Before;
 import org.junit.Test;
 
 @NoHttpd
 public class CustomLabelIT extends AbstractDaemonTest {
+  private static final String LABEL_NAME = "CustomLabel";
+  private static final LabelType LABEL =
+      label("CustomLabel", value(1, "Positive"), value(0, "No score"), value(-1, "Negative"));
+  private static final String P_LABEL_NAME = "CustomLabel2";
+  private static final LabelType P =
+      label("CustomLabel2", value(1, "Positive"), value(0, "No score"));
 
   @Inject private ProjectOperations projectOperations;
   @Inject private ExtensionRegistry extensionRegistry;
 
-  private final LabelType label =
-      label("CustomLabel", value(1, "Positive"), value(0, "No score"), value(-1, "Negative"));
-
-  private final LabelType P = label("CustomLabel2", value(1, "Positive"), value(0, "No score"));
-
   @Before
   public void setUp() throws Exception {
     projectOperations
         .project(project)
         .forUpdate()
-        .add(allowLabel(label.getName()).ref("refs/heads/*").group(ANONYMOUS_USERS).range(-1, 1))
-        .add(allowLabel(P.getName()).ref("refs/heads/*").group(ANONYMOUS_USERS).range(0, 1))
+        .add(allowLabel(LABEL_NAME).ref("refs/heads/*").group(ANONYMOUS_USERS).range(-1, 1))
+        .add(allowLabel(P_LABEL_NAME).ref("refs/heads/*").group(ANONYMOUS_USERS).range(0, 1))
         .update();
   }
 
   @Test
   public void customLabelNoOp_NegativeVoteNotBlock() throws Exception {
-    label.setFunction(NO_OP);
-    saveLabelConfig();
+    saveLabelConfig(LABEL.toBuilder().setFunction(NO_OP));
     PushOneCommit.Result r = createChange();
-    revision(r).review(new ReviewInput().label(label.getName(), -1));
+    revision(r).review(new ReviewInput().label(LABEL_NAME, -1));
     ChangeInfo c = getWithLabels(r);
-    LabelInfo q = c.labels.get(label.getName());
+    LabelInfo q = c.labels.get(LABEL_NAME);
     assertThat(q.all).hasSize(1);
     assertThat(q.approved).isNull();
     assertThat(q.recommended).isNull();
@@ -91,12 +91,11 @@
 
   @Test
   public void customLabelNoBlock_NegativeVoteNotBlock() throws Exception {
-    label.setFunction(NO_BLOCK);
-    saveLabelConfig();
+    saveLabelConfig(LABEL.toBuilder().setFunction(NO_BLOCK));
     PushOneCommit.Result r = createChange();
-    revision(r).review(new ReviewInput().label(label.getName(), -1));
+    revision(r).review(new ReviewInput().label(LABEL_NAME, -1));
     ChangeInfo c = getWithLabels(r);
-    LabelInfo q = c.labels.get(label.getName());
+    LabelInfo q = c.labels.get(LABEL_NAME);
     assertThat(q.all).hasSize(1);
     assertThat(q.approved).isNull();
     assertThat(q.recommended).isNull();
@@ -107,12 +106,11 @@
 
   @Test
   public void customLabelMaxNoBlock_NegativeVoteNotBlock() throws Exception {
-    label.setFunction(MAX_NO_BLOCK);
-    saveLabelConfig();
+    saveLabelConfig(LABEL.toBuilder().setFunction(MAX_NO_BLOCK));
     PushOneCommit.Result r = createChange();
-    revision(r).review(new ReviewInput().label(label.getName(), -1));
+    revision(r).review(new ReviewInput().label(LABEL_NAME, -1));
     ChangeInfo c = getWithLabels(r);
-    LabelInfo q = c.labels.get(label.getName());
+    LabelInfo q = c.labels.get(LABEL_NAME);
     assertThat(q.all).hasSize(1);
     assertThat(q.approved).isNull();
     assertThat(q.recommended).isNull();
@@ -123,16 +121,14 @@
 
   @Test
   public void customLabelMaxNoBlock_MaxVoteSubmittable() throws Exception {
-    label.setFunction(MAX_NO_BLOCK);
-    P.setFunction(NO_OP);
-    saveLabelConfig();
+    saveLabelConfig(LABEL.toBuilder().setFunction(MAX_NO_BLOCK), P.toBuilder().setFunction(NO_OP));
     PushOneCommit.Result r = createChange();
     assertThat(info(r.getChangeId()).submittable).isNull();
-    revision(r).review(ReviewInput.approve().label(label.getName(), 1));
+    revision(r).review(ReviewInput.approve().label(LABEL_NAME, 1));
 
     ChangeInfo c = getWithLabels(r);
     assertThat(c.submittable).isTrue();
-    LabelInfo q = c.labels.get(label.getName());
+    LabelInfo q = c.labels.get(LABEL_NAME);
     assertThat(q.all).hasSize(1);
     assertThat(q.approved).isNotNull();
     assertThat(q.recommended).isNull();
@@ -143,12 +139,11 @@
 
   @Test
   public void customLabelAnyWithBlock_NegativeVoteBlock() throws Exception {
-    label.setFunction(ANY_WITH_BLOCK);
-    saveLabelConfig();
+    saveLabelConfig(LABEL.toBuilder().setFunction(ANY_WITH_BLOCK));
     PushOneCommit.Result r = createChange();
-    revision(r).review(new ReviewInput().label(label.getName(), -1));
+    revision(r).review(new ReviewInput().label(LABEL_NAME, -1));
     ChangeInfo c = getWithLabels(r);
-    LabelInfo q = c.labels.get(label.getName());
+    LabelInfo q = c.labels.get(LABEL_NAME);
     assertThat(q.all).hasSize(1);
     assertThat(q.approved).isNull();
     assertThat(q.recommended).isNull();
@@ -170,19 +165,18 @@
   public void customLabelAnyWithBlock_Addreviewer_ZeroVote() throws Exception {
     TestListener testListener = new TestListener();
     try (Registration registration = extensionRegistry.newRegistration().add(testListener)) {
-      P.setFunction(ANY_WITH_BLOCK);
-      saveLabelConfig();
+      saveLabelConfig(P.toBuilder().setFunction(ANY_WITH_BLOCK));
       PushOneCommit.Result r = createChange();
       AddReviewerInput in = new AddReviewerInput();
       in.reviewer = user.email();
       gApi.changes().id(r.getChangeId()).addReviewer(in);
 
-      ReviewInput input = new ReviewInput().label(P.getName(), 0);
+      ReviewInput input = new ReviewInput().label(P_LABEL_NAME, 0);
       input.message = "foo";
 
       revision(r).review(input);
       ChangeInfo c = getWithLabels(r);
-      LabelInfo q = c.labels.get(P.getName());
+      LabelInfo q = c.labels.get(P_LABEL_NAME);
       assertThat(q.all).hasSize(1);
       assertThat(q.approved).isNull();
       assertThat(q.recommended).isNull();
@@ -196,12 +190,11 @@
 
   @Test
   public void customLabelMaxWithBlock_NegativeVoteBlock() throws Exception {
-    label.setFunction(MAX_WITH_BLOCK);
-    saveLabelConfig();
+    saveLabelConfig(LABEL.toBuilder().setFunction(MAX_WITH_BLOCK));
     PushOneCommit.Result r = createChange();
-    revision(r).review(new ReviewInput().label(label.getName(), -1));
+    revision(r).review(new ReviewInput().label(LABEL_NAME, -1));
     ChangeInfo c = getWithLabels(r);
-    LabelInfo q = c.labels.get(label.getName());
+    LabelInfo q = c.labels.get(LABEL_NAME);
     assertThat(q.all).hasSize(1);
     assertThat(q.approved).isNull();
     assertThat(q.recommended).isNull();
@@ -212,16 +205,15 @@
 
   @Test
   public void customLabelMaxWithBlock_MaxVoteSubmittable() throws Exception {
-    label.setFunction(MAX_WITH_BLOCK);
-    P.setFunction(NO_OP);
-    saveLabelConfig();
+    saveLabelConfig(
+        LABEL.toBuilder().setFunction(MAX_WITH_BLOCK), P.toBuilder().setFunction(NO_OP));
     PushOneCommit.Result r = createChange();
     assertThat(info(r.getChangeId()).submittable).isNull();
-    revision(r).review(ReviewInput.approve().label(label.getName(), 1));
+    revision(r).review(ReviewInput.approve().label(LABEL_NAME, 1));
 
     ChangeInfo c = getWithLabels(r);
     assertThat(c.submittable).isTrue();
-    LabelInfo q = c.labels.get(label.getName());
+    LabelInfo q = c.labels.get(LABEL_NAME);
     assertThat(q.all).hasSize(1);
     assertThat(q.approved).isNotNull();
     assertThat(q.recommended).isNull();
@@ -232,13 +224,12 @@
 
   @Test
   public void customLabelMaxWithBlock_MaxVoteNegativeVoteBlock() throws Exception {
-    label.setFunction(MAX_WITH_BLOCK);
-    saveLabelConfig();
+    saveLabelConfig(LABEL.toBuilder().setFunction(MAX_WITH_BLOCK));
     PushOneCommit.Result r = createChange();
-    revision(r).review(new ReviewInput().label(label.getName(), 1));
-    revision(r).review(new ReviewInput().label(label.getName(), -1));
+    revision(r).review(new ReviewInput().label(LABEL_NAME, 1));
+    revision(r).review(new ReviewInput().label(LABEL_NAME, -1));
     ChangeInfo c = getWithLabels(r);
-    LabelInfo q = c.labels.get(label.getName());
+    LabelInfo q = c.labels.get(LABEL_NAME);
     assertThat(q.all).hasSize(1);
     assertThat(q.approved).isNull();
     assertThat(q.recommended).isNull();
@@ -249,10 +240,9 @@
 
   @Test
   public void customLabel_DisallowPostSubmit() throws Exception {
-    label.setFunction(NO_OP);
-    label.setAllowPostSubmit(false);
-    P.setFunction(NO_OP);
-    saveLabelConfig();
+    saveLabelConfig(
+        LABEL.toBuilder().setFunction(NO_OP).setAllowPostSubmit(false),
+        P.toBuilder().setFunction(NO_OP));
 
     PushOneCommit.Result r = createChange();
     revision(r).review(ReviewInput.approve());
@@ -260,20 +250,20 @@
 
     ChangeInfo info = getWithLabels(r);
     assertPermitted(info, "Code-Review", 2);
-    assertPermitted(info, P.getName(), 0, 1);
-    assertPermitted(info, label.getName());
+    assertPermitted(info, P_LABEL_NAME, 0, 1);
+    assertPermitted(info, LABEL_NAME);
 
     ReviewInput postSubmitReview1 = new ReviewInput();
     postSubmitReview1.label(P.getName(), P.getMax().getValue());
     revision(r).review(postSubmitReview1);
 
     ReviewInput postSubmitReview2 = new ReviewInput();
-    postSubmitReview2.label(label.getName(), label.getMax().getValue());
+    postSubmitReview2.label(LABEL.getName(), LABEL.getMax().getValue());
     ResourceConflictException thrown =
         assertThrows(ResourceConflictException.class, () -> revision(r).review(postSubmitReview2));
     assertThat(thrown)
         .hasMessageThat()
-        .contains("Voting on labels disallowed after submit: " + label.getName());
+        .contains("Voting on labels disallowed after submit: " + LABEL_NAME);
   }
 
   @Test
@@ -331,10 +321,9 @@
 
   @Test
   public void customLabel_withBranch() throws Exception {
-    label.setRefPatterns(Arrays.asList("master"));
-    saveLabelConfig();
+    saveLabelConfig(LABEL.toBuilder().setRefPatterns(ImmutableList.of("master")));
     ProjectConfig cfg = projectCache.get(project).orElseThrow(illegalState(project)).getConfig();
-    assertThat(cfg.getLabelSections().get(label.getName()).getRefPatterns()).contains("master");
+    assertThat(cfg.getLabelSections().get(LABEL_NAME).getRefPatterns()).contains("master");
   }
 
   private void assertLabelStatus(String changeId, String testLabel) throws Exception {
@@ -348,10 +337,11 @@
     assertThat(labelInfo.blocking).isNull();
   }
 
-  private void saveLabelConfig() throws Exception {
+  private void saveLabelConfig(LabelType.Builder... builders) throws Exception {
     try (ProjectConfigUpdate u = updateProject(project)) {
-      u.getConfig().getLabelSections().put(label.getName(), label);
-      u.getConfig().getLabelSections().put(P.getName(), P);
+      for (LabelType.Builder b : builders) {
+        u.getConfig().upsertLabelType(b.build());
+      }
       u.save();
     }
   }
diff --git a/javatests/com/google/gerrit/acceptance/server/rules/IgnoreSelfApprovalRuleIT.java b/javatests/com/google/gerrit/acceptance/server/rules/IgnoreSelfApprovalRuleIT.java
index 1c820af..90d4e09 100644
--- a/javatests/com/google/gerrit/acceptance/server/rules/IgnoreSelfApprovalRuleIT.java
+++ b/javatests/com/google/gerrit/acceptance/server/rules/IgnoreSelfApprovalRuleIT.java
@@ -89,7 +89,7 @@
       if (localLabelSections.isEmpty()) {
         localLabelSections.putAll(projectCache.getAllProjects().getConfig().getLabelSections());
       }
-      localLabelSections.get(labelName).setIgnoreSelfApproval(newState);
+      u.getConfig().updateLabelType(labelName, lt -> lt.setIgnoreSelfApproval(newState));
       u.save();
     }
   }
diff --git a/javatests/com/google/gerrit/common/data/LabelFunctionTest.java b/javatests/com/google/gerrit/common/data/LabelFunctionTest.java
index 6f5232b..8fea072 100644
--- a/javatests/com/google/gerrit/common/data/LabelFunctionTest.java
+++ b/javatests/com/google/gerrit/common/data/LabelFunctionTest.java
@@ -87,12 +87,12 @@
   private static LabelType makeLabel() {
     List<LabelValue> values = new ArrayList<>();
     // The label text is irrelevant here, only the numerical value is used
-    values.add(new LabelValue((short) -2, "Great job, please fix compilation."));
-    values.add(new LabelValue((short) -1, "Really good, please make some minor changes."));
-    values.add(new LabelValue((short) 0, "No vote."));
-    values.add(new LabelValue((short) 1, "Closest thing perfection."));
-    values.add(new LabelValue((short) 2, "Perfect!"));
-    return new LabelType(LABEL_NAME, values);
+    values.add(LabelValue.create((short) -2, "Great job, please fix compilation."));
+    values.add(LabelValue.create((short) -1, "Really good, please make some minor changes."));
+    values.add(LabelValue.create((short) 0, "No vote."));
+    values.add(LabelValue.create((short) 1, "Closest thing perfection."));
+    values.add(LabelValue.create((short) 2, "Perfect!"));
+    return LabelType.create(LABEL_NAME, values);
   }
 
   private static PatchSetApproval makeApproval(int value) {
diff --git a/javatests/com/google/gerrit/common/data/LabelTypeTest.java b/javatests/com/google/gerrit/common/data/LabelTypeTest.java
index 6c3befb..76ea6e1 100644
--- a/javatests/com/google/gerrit/common/data/LabelTypeTest.java
+++ b/javatests/com/google/gerrit/common/data/LabelTypeTest.java
@@ -22,26 +22,26 @@
 public class LabelTypeTest {
   @Test
   public void sortLabelValues() {
-    LabelValue v0 = new LabelValue((short) 0, "Zero");
-    LabelValue v1 = new LabelValue((short) 1, "One");
-    LabelValue v2 = new LabelValue((short) 2, "Two");
-    LabelType types = new LabelType("Label", ImmutableList.of(v2, v0, v1));
+    LabelValue v0 = LabelValue.create((short) 0, "Zero");
+    LabelValue v1 = LabelValue.create((short) 1, "One");
+    LabelValue v2 = LabelValue.create((short) 2, "Two");
+    LabelType types = LabelType.create("Label", ImmutableList.of(v2, v0, v1));
     assertThat(types.getValues()).containsExactly(v0, v1, v2).inOrder();
   }
 
   @Test
   public void insertMissingLabelValues() {
-    LabelValue v0 = new LabelValue((short) 0, "Zero");
-    LabelValue v2 = new LabelValue((short) 2, "Two");
-    LabelValue v5 = new LabelValue((short) 5, "Five");
-    LabelType types = new LabelType("Label", ImmutableList.of(v2, v5, v0));
+    LabelValue v0 = LabelValue.create((short) 0, "Zero");
+    LabelValue v2 = LabelValue.create((short) 2, "Two");
+    LabelValue v5 = LabelValue.create((short) 5, "Five");
+    LabelType types = LabelType.create("Label", ImmutableList.of(v2, v5, v0));
     assertThat(types.getValues())
         .containsExactly(
             v0,
-            new LabelValue((short) 1, ""),
+            LabelValue.create((short) 1, ""),
             v2,
-            new LabelValue((short) 3, ""),
-            new LabelValue((short) 4, ""),
+            LabelValue.create((short) 3, ""),
+            LabelValue.create((short) 4, ""),
             v5)
         .inOrder();
   }
diff --git a/javatests/com/google/gerrit/server/change/LabelNormalizerTest.java b/javatests/com/google/gerrit/server/change/LabelNormalizerTest.java
index c259e60..ba8485b 100644
--- a/javatests/com/google/gerrit/server/change/LabelNormalizerTest.java
+++ b/javatests/com/google/gerrit/server/change/LabelNormalizerTest.java
@@ -105,7 +105,7 @@
     }
     LabelType lt =
         label("Verified", value(1, "Verified"), value(0, "No score"), value(-1, "Fails"));
-    pc.getLabelSections().put(lt.getName(), lt);
+    pc.upsertLabelType(lt);
     save(pc);
   }
 
diff --git a/javatests/com/google/gerrit/server/permissions/RefControlTest.java b/javatests/com/google/gerrit/server/permissions/RefControlTest.java
index ea92c8c..9029301 100644
--- a/javatests/com/google/gerrit/server/permissions/RefControlTest.java
+++ b/javatests/com/google/gerrit/server/permissions/RefControlTest.java
@@ -207,7 +207,7 @@
         ProjectConfig allProjectsConfig = projectConfigFactory.create(allProjectsName);
         allProjectsConfig.load(md);
         LabelType cr = TestLabels.codeReview();
-        allProjectsConfig.getLabelSections().put(cr.getName(), cr);
+        allProjectsConfig.upsertLabelType(cr);
         allProjectsConfig.commit(md);
       }
     }
diff --git a/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java b/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
index 331bb4c..4104017 100644
--- a/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
+++ b/javatests/com/google/gerrit/server/query/change/AbstractQueryChangesTest.java
@@ -1026,7 +1026,7 @@
     try (MetaDataUpdate md = metaDataUpdateFactory.create(project)) {
       ProjectConfig cfg = projectConfigFactory.create(project);
       cfg.load(md);
-      cfg.getLabelSections().put(verified.getName(), verified);
+      cfg.upsertLabelType(verified);
       cfg.commit(md);
     }
     projectCache.evict(project);
diff --git a/javatests/com/google/gerrit/server/rules/IgnoreSelfApprovalRuleTest.java b/javatests/com/google/gerrit/server/rules/IgnoreSelfApprovalRuleTest.java
index d8af0e5..85a3207 100644
--- a/javatests/com/google/gerrit/server/rules/IgnoreSelfApprovalRuleTest.java
+++ b/javatests/com/google/gerrit/server/rules/IgnoreSelfApprovalRuleTest.java
@@ -72,12 +72,12 @@
   private static LabelType makeLabel(String labelName) {
     List<LabelValue> values = new ArrayList<>();
     // The label text is irrelevant here, only the numerical value is used
-    values.add(new LabelValue((short) -2, "-2"));
-    values.add(new LabelValue((short) -1, "-1"));
-    values.add(new LabelValue((short) 0, "No vote."));
-    values.add(new LabelValue((short) 1, "+1"));
-    values.add(new LabelValue((short) 2, "+2"));
-    return new LabelType(labelName, values);
+    values.add(LabelValue.create((short) -2, "-2"));
+    values.add(LabelValue.create((short) -1, "-1"));
+    values.add(LabelValue.create((short) 0, "No vote."));
+    values.add(LabelValue.create((short) 1, "+1"));
+    values.add(LabelValue.create((short) 2, "+2"));
+    return LabelType.create(labelName, values);
   }
 
   private static PatchSetApproval makeApproval(LabelId labelId, Account.Id accountId, int value) {
diff --git a/javatests/com/google/gerrit/server/schema/AllProjectsCreatorTest.java b/javatests/com/google/gerrit/server/schema/AllProjectsCreatorTest.java
index eceec8b..9cf4896 100644
--- a/javatests/com/google/gerrit/server/schema/AllProjectsCreatorTest.java
+++ b/javatests/com/google/gerrit/server/schema/AllProjectsCreatorTest.java
@@ -44,12 +44,12 @@
 
 public class AllProjectsCreatorTest {
   private static final LabelType TEST_LABEL =
-      new LabelType(
+      LabelType.create(
           "Test-Label",
           ImmutableList.of(
-              new LabelValue((short) 2, "Two"),
-              new LabelValue((short) 0, "Zero"),
-              new LabelValue((short) 1, "One")));
+              LabelValue.create((short) 2, "Two"),
+              LabelValue.create((short) 0, "Zero"),
+              LabelValue.create((short) 1, "One")));
 
   private static final String TEST_LABEL_STRING =
       String.join(