Provide default shallowCommits getter and setter in ObjectDatabase

I649db9ae679ec2606cf7c530b040f8b6b93eb81a added a default implementation
for getShallowCommits and setShallowCommits to DfsObjDatabase, for the
convenience of any implementers that define subclasses. But we forgot
that some implementers inherit from ObjectDatabase directly instead.
Move the default getter and setter to the base class so that such
callers do not need source changes to unbreak their build.

This also lets us update the api_filters to reflect that this is no
longer an API-breaking change.

Change-Id: I5dcca462eb306e511e57907b7d9264d51b3f3014

2 files changed, 15 insertions, 18 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsObjDatabase.java b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsObjDatabase.java
index c50e03869c..46ec87df54 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsObjDatabase.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/internal/storage/dfs/DfsObjDatabase.java
@@ -29,7 +29,6 @@ import java.util.concurrent.atomic.AtomicReference;
 import org.eclipse.jgit.internal.storage.pack.PackExt;
 import org.eclipse.jgit.lib.AnyObjectId;
 import org.eclipse.jgit.lib.ObjectDatabase;
-import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.ObjectReader;
 
@@ -58,8 +57,6 @@ public abstract class DfsObjDatabase extends ObjectDatabase {
 		}
 	};
 
-	private static final Set<ObjectId> shallowCommits = Collections.emptySet();
-
 	/**
 	 * Sources for a pack file.
 	 * <p>
@@ -507,19 +504,6 @@ public abstract class DfsObjDatabase extends ObjectDatabase {
 	protected abstract DfsOutputStream writeFile(
 			DfsPackDescription desc, PackExt ext) throws IOException;
 
-	@Override
-	public Set<ObjectId> getShallowCommits() throws IOException {
-		return shallowCommits;
-	}
-
-	@Override
-	public void setShallowCommits(Set<ObjectId> shallowCommits) {
-		if (!shallowCommits.isEmpty()) {
-			throw new UnsupportedOperationException(
-					"Shallow commits expected to be empty.");
-		}
-	}
-
 	void addPack(DfsPackFile newPack) throws IOException {
 		PackList o, n;
 		do {
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectDatabase.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectDatabase.java
index 1c0f436090..a39766cbd0 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectDatabase.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/ObjectDatabase.java
@@ -11,6 +11,7 @@
 package org.eclipse.jgit.lib;
 
 import java.io.IOException;
+import java.util.Collections;
 import java.util.Set;
 
 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
@@ -23,6 +24,9 @@ import org.eclipse.jgit.errors.MissingObjectException;
  * {@link org.eclipse.jgit.lib.ObjectId}.
  */
 public abstract class ObjectDatabase implements AutoCloseable {
+
+	private static final Set<ObjectId> shallowCommits = Collections.emptySet();
+
 	/**
 	 * Initialize a new database instance for access.
 	 */
@@ -79,7 +83,10 @@ public abstract class ObjectDatabase implements AutoCloseable {
 	 *
 	 * @since 6.3
 	 */
-	public abstract Set<ObjectId> getShallowCommits() throws IOException;
+	public Set<ObjectId> getShallowCommits() throws IOException {
+		return shallowCommits;
+	}
+
 
 	/**
 	 * Update the shallow commits of the current repository
@@ -90,7 +97,13 @@ public abstract class ObjectDatabase implements AutoCloseable {
 	 *
 	 * @since 6.3
 	 */
-	public abstract void setShallowCommits(Set<ObjectId> shallowCommits) throws IOException;
+	public void setShallowCommits(Set<ObjectId> shallowCommits)
+			throws IOException {
+		if (!shallowCommits.isEmpty()) {
+			throw new UnsupportedOperationException(
+					"Shallow commits expected to be empty."); //$NON-NLS-1$
+		}
+	}
 
 	/**
 	 * Close any resources held by this database.