Subject: [PATCH JGIT] Method invokes inefficient Number constructor; use static valueOf instead

From: Yann Simon <[email-masked]>
Date: Thu, 19 Mar 2009 10:14:59 +0100

>>From FindBugs:
Using new Integer(int) is guaranteed to always result in a new object
whereas Integer.valueOf(int) allows caching of values to be done by the
compiler, class library, or JVM. Using of cached values avoids object
allocation and the code will be faster.
Values between -128 and 127 are guaranteed to have corresponding cached
instances and using valueOf is approximately 3.5 times faster than using
constructor. For values outside the constant range the performance of
both styles is the same.

Signed-off-by: Yann Simon <[email-masked]>
---
 .../jgit/errors/NoClosingBracketException.java     |    4 ++--
 .../src/org/spearce/jgit/transport/IndexPack.java  |    6 +++---
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/org.spearce.jgit/src/org/spearce/jgit/errors/NoClosingBracketException.java b/org.spearce.jgit/src/org/spearce/jgit/errors/NoClosingBracketException.java
index 8fe9ab1..b325b45 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/errors/NoClosingBracketException.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/errors/NoClosingBracketException.java
@@ -64,7 +64,7 @@ super(createMessage(indexOfOpeningBracket, openingBracket,
 	private static String createMessage(final int indexOfOpeningBracket,
 			final String openingBracket, final String closingBracket) {
 		return String.format("No closing %s found for %s at index %s.",
-				closingBracket, openingBracket, new Integer(
-						indexOfOpeningBracket));
+				closingBracket, openingBracket,
+				Integer.valueOf(indexOfOpeningBracket));
 	}
 }
diff --git a/org.spearce.jgit/src/org/spearce/jgit/transport/IndexPack.java b/org.spearce.jgit/src/org/spearce/jgit/transport/IndexPack.java
index e0e4855..04ef59d 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/transport/IndexPack.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/transport/IndexPack.java
@@ -383,7 +383,7 @@ private void resolveDeltas(final ProgressMonitor progress)
 	private void resolveDeltas(final PackedObjectInfo oe) throws IOException {
 		final int oldCRC = oe.getCRC();
 		if (baseById.containsKey(oe)
-				|| baseByPos.containsKey(new Long(oe.getOffset())))
+				|| baseByPos.containsKey(Long.valueOf(oe.getOffset())))
 			resolveDeltas(oe.getOffset(), oldCRC, Constants.OBJ_BAD, null, oe);
 	}
 
@@ -448,7 +448,7 @@ private void resolveDeltas(final long pos, final int oldCRC, int type,
 	private void resolveChildDeltas(final long pos, int type, byte[] data,
 			PackedObjectInfo oe) throws IOException {
 		final ArrayList<UnresolvedDelta> a = baseById.remove(oe);
-		final ArrayList<UnresolvedDelta> b = baseByPos.remove(new Long(pos));
+		final ArrayList<UnresolvedDelta> b = baseByPos.remove(Long.valueOf(pos));
 		int ai = 0, bi = 0;
 		if (a != null && b != null) {
 			while (ai < a.size() && bi < b.size()) {
@@ -679,7 +679,7 @@ private void indexOneObject() throws IOException {
 				ofs <<= 7;
 				ofs += (c & 127);
 			}
-			final Long base = new Long(pos - ofs);
+			final Long base = Long.valueOf(pos - ofs);
 			ArrayList<UnresolvedDelta> r = baseByPos.get(base);
 			if (r == null) {
 				r = new ArrayList<UnresolvedDelta>(8);
-- 
1.6.1.2