Expose AnyObjectId compareTo(byte[]) and compareTo(int[])

Storage systems can use these implementations to compare a passed
AnyObjectId with a stored representation of an ObjectId in the
canonical network byte order format.  This can be useful to do a
binary search, or just linear scan, over an encoded storage file.

Change-Id: I8c72993c4f4c6e98d599ac2c9867453752f25fd2
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

1 files changed, 24 insertions, 2 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/AnyObjectId.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/AnyObjectId.java
index d4d53574b3..7d08f3d4c9 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/AnyObjectId.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/AnyObjectId.java
@@ -142,7 +142,18 @@ public abstract class AnyObjectId implements Comparable {
 		return compareTo(((ObjectId) other));
 	}
 
-	int compareTo(final byte[] bs, final int p) {
+	/**
+	 * Compare this ObjectId to a network-byte-order ObjectId.
+	 *
+	 * @param bs
+	 *            array containing the other ObjectId in network byte order.
+	 * @param p
+	 *            position within {@code bs} to start the compare at. At least
+	 *            20 bytes, starting at this position are required.
+	 * @return a negative integer, zero, or a positive integer as this object is
+	 *         less than, equal to, or greater than the specified object.
+	 */
+	public int compareTo(final byte[] bs, final int p) {
 		int cmp;
 
 		cmp = NB.compareUInt32(w1, NB.decodeInt32(bs, p));
@@ -164,7 +175,18 @@ public abstract class AnyObjectId implements Comparable {
 		return NB.compareUInt32(w5, NB.decodeInt32(bs, p + 16));
 	}
 
-	int compareTo(final int[] bs, final int p) {
+	/**
+	 * Compare this ObjectId to a network-byte-order ObjectId.
+	 *
+	 * @param bs
+	 *            array containing the other ObjectId in network byte order.
+	 * @param p
+	 *            position within {@code bs} to start the compare at. At least 5
+	 *            integers, starting at this position are required.
+	 * @return a negative integer, zero, or a positive integer as this object is
+	 *         less than, equal to, or greater than the specified object.
+	 */
+	public int compareTo(final int[] bs, final int p) {
 		int cmp;
 
 		cmp = NB.compareUInt32(w1, bs[p]);