TemporaryBuffer: Clear block pointer list instead of reallocating

The block pointer list may have been relatively large, so no need to
make more garbage. Instead, just clear the list and null out all the
elements.

Another possible motivation: a caller may have provided an inaccurate
estimated size, so the list might have been resized several times. If
the list is reused later for a similarly underestimated workload, this
fix will prevent additional resizing on subsequent usages.

Change-Id: I511675035dcff1117381a46c294cc11aded10893

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/util/TemporaryBuffer.java b/org.eclipse.jgit/src/org/eclipse/jgit/util/TemporaryBuffer.java
index 0a8c5945d9959b074010326275e594d8c3820863..006c3c0a0102d0a634851ff3c751f5f50a5c5229 100644 (file)
--- a/org.eclipse.jgit/src/org/eclipse/jgit/util/TemporaryBuffer.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/util/TemporaryBuffer.java
@@ -291,13 +291,11 @@ public abstract class TemporaryBuffer extends OutputStream {
                if (overflow != null) {
                        destroy();
                }
-               if (inCoreLimit < Block.SZ) {
-                       blocks = new ArrayList<Block>(1);
-                       blocks.add(new Block(inCoreLimit));
-               } else {
+               if (blocks != null)
+                       blocks.clear();
+               else
                        blocks = new ArrayList<Block>(initialBlocks);
-                       blocks.add(new Block());
-               }
+               blocks.add(new Block(Math.min(inCoreLimit, Block.SZ)));
        }
 
        /**