From 3534fa9c61e0bcc94075b99e08283bd42bbb21f0 Mon Sep 17 00:00:00 2001
From: "Shawn O. Pearce" <spearce@spearce.org>
Date: Mon, 23 Jul 2012 15:50:52 -0700
Subject: [PATCH] Expose some DFS APIs as public or protected

Expose class DfsReader and method DfsPackFile.hasObject() as public.
Applications may want to be able to inquire about some details of
the storage of a repository. Make this possible by exposing some
simple accessor methods.

Expose method DfsObjDatabase.clearCache() as protected, allowing
implementing subclasses to dump the cache if necessary, and force
it to reload on a future request.

Change-Id: Ic592c82d45ace9f2fa5f8d7e4bacfdce96dea969
---
 .../eclipse/jgit/storage/dfs/DfsObjDatabase.java   |  3 ++-
 .../org/eclipse/jgit/storage/dfs/DfsPackFile.java  | 14 +++++++++++++-
 .../org/eclipse/jgit/storage/dfs/DfsReader.java    |  8 +++++++-
 3 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsObjDatabase.java b/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsObjDatabase.java
index b1290d955..32244c1b0 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsObjDatabase.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsObjDatabase.java
@@ -423,7 +423,8 @@ private static Map<DfsPackDescription, DfsPackFile> reuseMap(PackList old) {
 		return forReuse;
 	}
 
-	void clearCache() {
+	/** Clears the cached list of packs, forcing them to be scanned again. */
+	protected void clearCache() {
 		packList.set(NO_PACKS);
 	}
 
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsPackFile.java b/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsPackFile.java
index 419e1e872..daad02a14 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsPackFile.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsPackFile.java
@@ -272,7 +272,19 @@ private PackReverseIndex getReverseIdx(DfsReader ctx) throws IOException {
 		}
 	}
 
-	boolean hasObject(DfsReader ctx, AnyObjectId id) throws IOException {
+	/**
+	 * Check if an object is stored within this pack.
+	 *
+	 * @param ctx
+	 *            reader context to support reading from the backing store if
+	 *            the index is not already loaded in memory.
+	 * @param id
+	 *            object to be located.
+	 * @return true if the object exists in this pack; false if it does not.
+	 * @throws IOException
+	 *             the pack index is not available, or is corrupt.
+	 */
+	public boolean hasObject(DfsReader ctx, AnyObjectId id) throws IOException {
 		final long offset = idx(ctx).findOffset(id);
 		return 0 < offset && !isCorrupt(offset);
 	}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsReader.java b/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsReader.java
index 3e2a0ad5c..6a76258ed 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsReader.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/storage/dfs/DfsReader.java
@@ -90,7 +90,13 @@
 import org.eclipse.jgit.storage.pack.PackWriter;
 import org.eclipse.jgit.util.BlockList;
 
-final class DfsReader extends ObjectReader implements ObjectReuseAsIs {
+/**
+ * Reader to access repository content through.
+ * <p>
+ * See the base {@link ObjectReader} documentation for details. Notably, a
+ * reader is not thread safe.
+ */
+public final class DfsReader extends ObjectReader implements ObjectReuseAsIs {
 	/** Temporary buffer large enough for at least one raw object id. */
 	final byte[] tempId = new byte[OBJECT_ID_LENGTH];