Use StringBuilder instead of String concatenation to avoid O(n^2) performance.
Change-Id: Ib1660d51a8a9c74f0eec6143f5b01cca833259df
diff --git a/java/com/google/gerrit/server/patch/SubmitWithStickyApprovalDiff.java b/java/com/google/gerrit/server/patch/SubmitWithStickyApprovalDiff.java
index 9f58aaf..63e0b7a 100644
--- a/java/com/google/gerrit/server/patch/SubmitWithStickyApprovalDiff.java
+++ b/java/com/google/gerrit/server/patch/SubmitWithStickyApprovalDiff.java
@@ -88,8 +88,10 @@
// If the latest approved patchset is the current patchset, no need to return anything.
return "";
}
- String diff =
- String.format("\n\n%d is the latest approved patch-set.\n", latestApprovedPatchsetId.get());
+ StringBuilder diff =
+ new StringBuilder(
+ String.format(
+ "\n\n%d is the latest approved patch-set.\n", latestApprovedPatchsetId.get()));
PatchList patchList =
getPatchList(
notes.getProjectName(),
@@ -103,19 +105,19 @@
.collect(Collectors.toList());
if (patchListEntryList.isEmpty()) {
- diff +=
- "No files were changed between the latest approved patch-set and the submitted one.\n";
- return diff;
+ diff.append(
+ "No files were changed between the latest approved patch-set and the submitted one.\n");
+ return diff.toString();
}
- diff += "The change was submitted with unreviewed changes in the following files:\n\n";
+ diff.append("The change was submitted with unreviewed changes in the following files:\n\n");
for (PatchListEntry patchListEntry : patchListEntryList) {
- diff +=
+ diff.append(
getDiffForFile(
- notes, currentPatchset.id(), latestApprovedPatchsetId, patchListEntry, currentUser);
+ notes, currentPatchset.id(), latestApprovedPatchsetId, patchListEntry, currentUser));
}
- return diff;
+ return diff.toString();
}
private String getDiffForFile(
@@ -126,12 +128,13 @@
CurrentUser currentUser)
throws AuthException, InvalidChangeOperationException, IOException,
PermissionBackendException {
- String diff =
- String.format(
- "The name of the file: %s\nInsertions: %d, Deletions: %d.\n\n",
- patchListEntry.getNewName(),
- patchListEntry.getInsertions(),
- patchListEntry.getDeletions());
+ StringBuilder diff =
+ new StringBuilder(
+ String.format(
+ "The name of the file: %s\nInsertions: %d, Deletions: %d.\n\n",
+ patchListEntry.getNewName(),
+ patchListEntry.getInsertions(),
+ patchListEntry.getDeletions()));
DiffPreferencesInfo diffPreferencesInfo = createDefaultDiffPreferencesInfo();
PatchScriptFactory patchScriptFactory =
patchScriptFactoryFactory.create(
@@ -145,66 +148,66 @@
try {
patchScript = patchScriptFactory.call();
} catch (LargeObjectException exception) {
- diff += "The file content is too large for showing the full diff. \n\n";
- return diff;
+ diff.append("The file content is too large for showing the full diff. \n\n");
+ return diff.toString();
}
if (patchScript.getChangeType() == ChangeType.RENAMED) {
- diff +=
+ diff.append(
String.format(
"The file %s was renamed to %s\n",
- patchListEntry.getOldName(), patchListEntry.getNewName());
+ patchListEntry.getOldName(), patchListEntry.getNewName()));
}
SparseFileContent.Accessor fileA = patchScript.getA().createAccessor();
SparseFileContent.Accessor fileB = patchScript.getB().createAccessor();
boolean editsExist = false;
if (patchScript.getEdits().stream().anyMatch(e -> e.getType() != Edit.Type.EMPTY)) {
- diff += "```\n";
+ diff.append("```\n");
editsExist = true;
}
for (Edit edit : patchScript.getEdits()) {
- diff += getDiffForEdit(fileA, fileB, edit);
+ diff.append(getDiffForEdit(fileA, fileB, edit));
}
if (editsExist) {
- diff += "```\n";
+ diff.append("```\n");
}
- return diff;
+ return diff.toString();
}
private String getDiffForEdit(Accessor fileA, Accessor fileB, Edit edit) {
- String diff = "";
+ StringBuilder diff = new StringBuilder();
Edit.Type type = edit.getType();
switch (type) {
case INSERT:
- diff += String.format("@@ +%d:%d @@\n", edit.getBeginB(), edit.getEndB());
- diff += getModifiedLines(fileB, edit.getBeginB(), edit.getEndB(), '+');
- diff += "\n";
+ diff.append(String.format("@@ +%d:%d @@\n", edit.getBeginB(), edit.getEndB()));
+ diff.append(getModifiedLines(fileB, edit.getBeginB(), edit.getEndB(), '+'));
+ diff.append("\n");
break;
case DELETE:
- diff += String.format("@@ -%d:%d @@\n", edit.getBeginA(), edit.getEndA());
- diff += getModifiedLines(fileA, edit.getBeginA(), edit.getEndA(), '-');
- diff += "\n";
+ diff.append(String.format("@@ -%d:%d @@\n", edit.getBeginA(), edit.getEndA()));
+ diff.append(getModifiedLines(fileA, edit.getBeginA(), edit.getEndA(), '-'));
+ diff.append("\n");
break;
case REPLACE:
- diff +=
+ diff.append(
String.format(
"@@ -%d:%d, +%d:%d @@\n",
- edit.getBeginA(), edit.getEndA(), edit.getBeginB(), edit.getEndB());
- diff += getModifiedLines(fileA, edit.getBeginA(), edit.getEndA(), '-');
- diff += getModifiedLines(fileB, edit.getBeginB(), edit.getEndB(), '+');
- diff += "\n";
+ edit.getBeginA(), edit.getEndA(), edit.getBeginB(), edit.getEndB()));
+ diff.append(getModifiedLines(fileA, edit.getBeginA(), edit.getEndA(), '-'));
+ diff.append(getModifiedLines(fileB, edit.getBeginB(), edit.getEndB(), '+'));
+ diff.append("\n");
break;
case EMPTY:
// do nothing since there is no change here.
}
- return diff;
+ return diff.toString();
}
private String getModifiedLines(Accessor file, int begin, int end, char modificationType) {
- String diff = "";
+ StringBuilder diff = new StringBuilder();
for (int i = begin; i < end; i++) {
- diff += String.format("%c %s\n", modificationType, file.get(i));
+ diff.append(String.format("%c %s\n", modificationType, file.get(i)));
}
- return diff;
+ return diff.toString();
}
private DiffPreferencesInfo createDefaultDiffPreferencesInfo() {
