Adding sorting to LongList

Sorting the array can be useful when its being used as a map of pairs
that are appended into the array and then later merge-joined against
another array of similar semantics.

Change-Id: I2e346ef5c99ed1347ec0345b44cda0bc29d03e90
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit/src/org/eclipse/jgit/util/LongList.java

@@ -44,6 +44,8 @@
 
 package org.eclipse.jgit.util;
 
+import java.util.Arrays;
+
 /** A more efficient List<Long> using a primitive long array. */
 public class LongList {
 	private long[] entries;
@@ -146,6 +148,11 @@ public class LongList {
 			add(val);
 	}
 
+	/** Sort the list of longs according to their natural ordering. */
+	public void sort() {
+		Arrays.sort(entries, 0, count);
+	}
+
 	private void grow() {
 		final long[] n = new long[(entries.length + 16) * 3 / 2];
 		System.arraycopy(entries, 0, n, 0, count);