diff --git a/src/main/java/com/googlesource/gerrit/plugins/automerger/ConfigLoader.java b/src/main/java/com/googlesource/gerrit/plugins/automerger/ConfigLoader.java
index f99b3fe..ef5379c 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/automerger/ConfigLoader.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/automerger/ConfigLoader.java
@@ -217,7 +217,7 @@
     if (toBranch == null) {
       throw new IllegalArgumentException("toBranch cannot be null");
     }
-    Set<String> upstreamBranches = new HashSet<String>();
+    Set<String> upstreamBranches = new HashSet<>();
     // List all subsections of automerger, split by :
     Set<String> subsections = getConfig().getSubsections(pluginName);
     for (String subsection : subsections) {
@@ -250,7 +250,7 @@
    */
   public Set<String> getDownstreamBranches(String fromBranch, String project)
       throws RestApiException, IOException, ConfigInvalidException {
-    Set<String> downstreamBranches = new HashSet<String>();
+    Set<String> downstreamBranches = new HashSet<>();
     // List all subsections of automerger, split by :
     Set<String> subsections = getConfig().getSubsections(pluginName);
     for (String subsection : subsections) {
diff --git a/src/main/java/com/googlesource/gerrit/plugins/automerger/DownstreamCreator.java b/src/main/java/com/googlesource/gerrit/plugins/automerger/DownstreamCreator.java
index 1d49922..4bd1a6c 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/automerger/DownstreamCreator.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/automerger/DownstreamCreator.java
@@ -570,7 +570,7 @@
     }
 
     // Map whether or not we should merge it or skip it for each downstream
-    Map<String, Boolean> dsBranchMap = new HashMap<String, Boolean>();
+    Map<String, Boolean> dsBranchMap = new HashMap<>();
     for (String downstreamBranch : downstreamBranches) {
       boolean isSkipMerge = config.isSkipMerge(change.branch, downstreamBranch, change.subject);
       dsBranchMap.put(downstreamBranch, !isSkipMerge);
@@ -619,7 +619,7 @@
     log.debug("Giving {} for label {} to {}", vote, label, change.id);
     // Vote on all downstream branches unless merge conflict.
     ReviewInput reviewInput = new ReviewInput();
-    Map<String, Short> labels = new HashMap<String, Short>();
+    Map<String, Short> labels = new HashMap<>();
     labels.put(label, vote);
     reviewInput.labels = labels;
     reviewInput.notify = NotifyHandling.NONE;
diff --git a/src/main/java/com/googlesource/gerrit/plugins/automerger/FailedMergeException.java b/src/main/java/com/googlesource/gerrit/plugins/automerger/FailedMergeException.java
index 2813c60..96c567c 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/automerger/FailedMergeException.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/automerger/FailedMergeException.java
@@ -57,7 +57,7 @@
    * @return A string representation of the conflicts.
    */
   public String getDisplayString() {
-    List<String> conflictMessages = new ArrayList<String>();
+    List<String> conflictMessages = new ArrayList<>();
     for (Map.Entry<String, String> branchMapEntry : failedMergeBranchMap.entrySet()) {
       String branch = branchMapEntry.getKey();
       String mergeConflictMessage = branchMapEntry.getValue();
diff --git a/src/main/java/com/googlesource/gerrit/plugins/automerger/ManifestReader.java b/src/main/java/com/googlesource/gerrit/plugins/automerger/ManifestReader.java
index 80d26c0..a71e1c0 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/automerger/ManifestReader.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/automerger/ManifestReader.java
@@ -48,7 +48,7 @@
    * @return The set of projects in the manifest.
    */
   public Set<String> getProjects() {
-    Set<String> projectSet = new HashSet<String>();
+    Set<String> projectSet = new HashSet<>();
 
     try {
       DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
diff --git a/src/main/java/com/googlesource/gerrit/plugins/automerger/QueryBuilder.java b/src/main/java/com/googlesource/gerrit/plugins/automerger/QueryBuilder.java
index 9defd08..ff5767c 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/automerger/QueryBuilder.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/automerger/QueryBuilder.java
@@ -24,7 +24,7 @@
   private Map<String, String> queryStringMap;
 
   public QueryBuilder() {
-    this.queryStringMap = new HashMap<String, String>();
+    this.queryStringMap = new HashMap<>();
   }
 
   public void addParameter(String key, String value) throws InvalidQueryParameterException {
@@ -48,7 +48,7 @@
   }
 
   public String get() {
-    List<String> queryStringList = new ArrayList<String>();
+    List<String> queryStringList = new ArrayList<>();
     for (Map.Entry<String, String> entry : queryStringMap.entrySet()) {
       queryStringList.add(entry.getKey() + ":" + entry.getValue());
     }
diff --git a/src/test/java/com/googlesource/gerrit/plugins/automerger/ConfigLoaderIT.java b/src/test/java/com/googlesource/gerrit/plugins/automerger/ConfigLoaderIT.java
index 3817c3e..d07fded 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/automerger/ConfigLoaderIT.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/automerger/ConfigLoaderIT.java
@@ -57,7 +57,7 @@
   @Test
   public void getProjectsInScopeTest_addProjects() throws Exception {
     defaultSetup("automerger.config");
-    Set<String> expectedProjects = new HashSet<String>();
+    Set<String> expectedProjects = new HashSet<>();
     expectedProjects.add("platform/whee");
     expectedProjects.add("platform/added/project");
     assertThat(configLoader.getProjectsInScope("master", "ds_one")).isEqualTo(expectedProjects);
@@ -66,7 +66,7 @@
   @Test
   public void getProjectsInScopeTest_setProjects() throws Exception {
     defaultSetup("automerger.config");
-    Set<String> otherExpectedProjects = new HashSet<String>();
+    Set<String> otherExpectedProjects = new HashSet<>();
     otherExpectedProjects.add("platform/some/project");
     otherExpectedProjects.add("platform/other/project");
     otherExpectedProjects.add("platform/added/project");
@@ -87,7 +87,7 @@
   @Test
   public void getProjectsInScope_ignoreSourceManifest() throws Exception {
     defaultSetup("alternate.config");
-    Set<String> expectedProjects = new HashSet<String>();
+    Set<String> expectedProjects = new HashSet<>();
     expectedProjects.add("platform/whee");
     expectedProjects.add("whuu");
     assertThat(configLoader.getProjectsInScope("master", "ds_two")).isEqualTo(expectedProjects);
@@ -150,7 +150,7 @@
   @Test
   public void upstreamBranchesTest() throws Exception {
     defaultSetup("automerger.config");
-    Set<String> expectedBranches = new HashSet<String>();
+    Set<String> expectedBranches = new HashSet<>();
     expectedBranches.add("master");
     assertThat(configLoader.getUpstreamBranches("ds_two", "platform/some/project"))
         .isEqualTo(expectedBranches);
@@ -159,7 +159,7 @@
   @Test
   public void upstreamBranchesTest_nonexistentBranch() throws Exception {
     defaultSetup("automerger.config");
-    Set<String> expectedBranches = new HashSet<String>();
+    Set<String> expectedBranches = new HashSet<>();
     assertThat(configLoader.getUpstreamBranches("master", "platform/some/project"))
         .isEqualTo(expectedBranches);
   }
@@ -167,7 +167,7 @@
   @Test
   public void downstreamBranchesTest() throws Exception {
     defaultSetup("automerger.config");
-    Set<String> expectedBranches = new HashSet<String>();
+    Set<String> expectedBranches = new HashSet<>();
     expectedBranches.add("ds_two");
     assertThat(configLoader.getDownstreamBranches("master", "platform/some/project"))
         .isEqualTo(expectedBranches);
@@ -176,7 +176,7 @@
   @Test
   public void downstreamBranchesTest_nonexistentBranch() throws Exception {
     defaultSetup("automerger.config");
-    Set<String> expectedBranches = new HashSet<String>();
+    Set<String> expectedBranches = new HashSet<>();
     assertThat(configLoader.getDownstreamBranches("idontexist", "platform/some/project"))
         .isEqualTo(expectedBranches);
   }
diff --git a/src/test/java/com/googlesource/gerrit/plugins/automerger/FailedMergeExceptionTest.java b/src/test/java/com/googlesource/gerrit/plugins/automerger/FailedMergeExceptionTest.java
index f7c0cdc..b3e6ba4 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/automerger/FailedMergeExceptionTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/automerger/FailedMergeExceptionTest.java
@@ -35,7 +35,7 @@
 
   @Before
   public void setUp() throws Exception {
-    failedMergeBranches = new TreeMap<String, String>();
+    failedMergeBranches = new TreeMap<>();
     failedMergeBranches.put("branch1", "branch1 merge conflict");
     failedMergeBranches.put("branch2", "branch2 merge conflict");
     failedMergeBranches.put("branch3", "branch3 merge conflict");
diff --git a/src/test/java/com/googlesource/gerrit/plugins/automerger/ManifestReaderTest.java b/src/test/java/com/googlesource/gerrit/plugins/automerger/ManifestReaderTest.java
index faeffa8..256b798 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/automerger/ManifestReaderTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/automerger/ManifestReaderTest.java
@@ -39,7 +39,7 @@
 
   @Test
   public void basicParseTest() throws Exception {
-    Set<String> expectedSet = new HashSet<String>();
+    Set<String> expectedSet = new HashSet<>();
     expectedSet.add("platform/whee");
     expectedSet.add("whoo");
     assertThat(manifestReader.getProjects()).isEqualTo(expectedSet);
@@ -48,7 +48,7 @@
   @Test
   public void branchDifferentFromDefaultRevisionTest() throws Exception {
     ManifestReader aospManifestReader = new ManifestReader("mirror-aosp-master", manifestString);
-    Set<String> expectedSet = new HashSet<String>();
+    Set<String> expectedSet = new HashSet<>();
     expectedSet.add("platform/whaa");
     assertThat(aospManifestReader.getProjects()).isEqualTo(expectedSet);
   }
diff --git a/src/test/java/com/googlesource/gerrit/plugins/automerger/MergeValidatorIT.java b/src/test/java/com/googlesource/gerrit/plugins/automerger/MergeValidatorIT.java
index 60001a5..0608d63 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/automerger/MergeValidatorIT.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/automerger/MergeValidatorIT.java
@@ -190,7 +190,7 @@
   }
 
   private List<ChangeInfo> sortedChanges(List<ChangeInfo> changes) {
-    List<ChangeInfo> listCopy = new ArrayList<ChangeInfo>(changes);
+    List<ChangeInfo> listCopy = new ArrayList<>(changes);
     Collections.sort(
         listCopy,
         new Comparator<ChangeInfo>() {