Start using ObjectInserter instead of ObjectWriter

Some newer style APIs are updated to use the newer ObjectInserter
interface instead of the now deprecated ObjectWriter.  In many of
the unit tests we don't bother to release the inserter, these are
typically using the file backend which doesn't need a release,
but in the future should use an in-memory HashMap based store,
which really wouldn't need it either.

Change-Id: I91a15e1dc42da68e6715397814e30fbd87fa2e73
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/TestRepository.java

@@ -79,7 +79,7 @@
 import org.eclipse.jgit.lib.ObjectChecker;
 import org.eclipse.jgit.lib.ObjectDirectory;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectWriter;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.PackFile;
 import org.eclipse.jgit.lib.PackWriter;
 import org.eclipse.jgit.lib.PersonIdent;
@@ -128,7 +128,7 @@ public class TestRepository<R extends Repository> {
 
 	private final RevWalk pool;
 
-	private final ObjectWriter writer;
+	private final ObjectInserter inserter;
 
 	private long now;
 
@@ -155,7 +155,7 @@ public TestRepository(R db) throws IOException {
 	public TestRepository(R db, RevWalk rw) throws IOException {
 		this.db = db;
 		this.pool = rw;
-		this.writer = new ObjectWriter(db);
+		this.inserter = db.newObjectInserter();
 		this.now = 1236977987000L;
 	}
 
@@ -205,7 +205,14 @@ public RevBlob blob(final String content) throws Exception {
 	 * @throws Exception
 	 */
 	public RevBlob blob(final byte[] content) throws Exception {
-		return pool.lookupBlob(writer.writeBlob(content));
+		ObjectId id;
+		try {
+			id = inserter.insert(Constants.OBJ_BLOB, content);
+			inserter.flush();
+		} finally {
+			inserter.release();
+		}
+		return pool.lookupBlob(id);
 	}
 
 	/**
@@ -241,7 +248,14 @@ public RevTree tree(final DirCacheEntry... entries) throws Exception {
 		for (final DirCacheEntry e : entries)
 			b.add(e);
 		b.finish();
-		return pool.lookupTree(dc.writeTree(writer));
+		ObjectId root;
+		try {
+			root = dc.writeTree(inserter);
+			inserter.flush();
+		} finally {
+			inserter.release();
+		}
+		return pool.lookupTree(root);
 	}
 
 	/**
@@ -351,7 +365,14 @@ public RevCommit commit(final int secDelta, final RevTree tree,
 		c.setAuthor(new PersonIdent(author, new Date(now)));
 		c.setCommitter(new PersonIdent(committer, new Date(now)));
 		c.setMessage("");
-		return pool.lookupCommit(writer.writeCommit(c));
+		ObjectId id;
+		try {
+			id = inserter.insert(Constants.OBJ_COMMIT, inserter.format(c));
+			inserter.flush();
+		} finally {
+			inserter.release();
+		}
+		return pool.lookupCommit(id);
 	}
 
 	/** @return a new commit builder. */
@@ -382,7 +403,14 @@ public RevTag tag(final String name, final RevObject dst) throws Exception {
 		t.setTag(name);
 		t.setTagger(new PersonIdent(committer, new Date(now)));
 		t.setMessage("");
-		return (RevTag) pool.lookupAny(writer.writeTag(t), Constants.OBJ_TAG);
+		ObjectId id;
+		try {
+			id = inserter.insert(Constants.OBJ_TAG, inserter.format(t));
+			inserter.flush();
+		} finally {
+			inserter.release();
+		}
+		return (RevTag) pool.lookupAny(id, Constants.OBJ_TAG);
 	}
 
 	/**
@@ -777,13 +805,21 @@ public RevCommit create() throws Exception {
 				TestRepository.this.tick(tick);
 
 				final Commit c = new Commit(db);
-				c.setTreeId(pool.lookupTree(tree.writeTree(writer)));
 				c.setParentIds(parents.toArray(new RevCommit[parents.size()]));
 				c.setAuthor(new PersonIdent(author, new Date(now)));
 				c.setCommitter(new PersonIdent(committer, new Date(now)));
 				c.setMessage(message);
 
-				self = pool.lookupCommit(writer.writeCommit(c));
+				ObjectId commitId;
+				try {
+					c.setTreeId(tree.writeTree(inserter));
+					commitId = inserter.insert(Constants.OBJ_COMMIT, inserter
+							.format(c));
+					inserter.flush();
+				} finally {
+					inserter.release();
+				}
+				self = pool.lookupCommit(commitId);
 
 				if (branch != null)
 					branch.update(self);

org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/ReadTreeTest.java

@@ -123,11 +123,15 @@ private Tree buildTree(HashMap<String, String> headEntries) throws IOException {
 	}
 
 	ObjectId genSha1(String data) {
-		ObjectWriter objectWriter = new ObjectWriter(db);
+		ObjectInserter w = db.newObjectInserter();
 		try {
-			return objectWriter.writeBlob(data.getBytes());
+			ObjectId id = w.insert(Constants.OBJ_BLOB, data.getBytes());
+			w.flush();
+			return id;
 		} catch (IOException e) {
 			fail(e.toString());
+		} finally {
+			w.release();
 		}
 		return null;
 	}

org.eclipse.jgit.test/tst/org/eclipse/jgit/merge/CherryPickTest.java

@@ -44,7 +44,8 @@
 
 package org.eclipse.jgit.merge;
 
-import java.io.ByteArrayInputStream;
+import static org.eclipse.jgit.lib.Constants.OBJ_BLOB;
+import static org.eclipse.jgit.lib.Constants.OBJ_COMMIT;
 
 import org.eclipse.jgit.dircache.DirCache;
 import org.eclipse.jgit.dircache.DirCacheBuilder;
@@ -53,7 +54,7 @@
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectWriter;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.RepositoryTestCase;
 import org.eclipse.jgit.treewalk.TreeWalk;
@@ -93,7 +94,7 @@ public void testPick() throws Exception {
 			t.finish();
 		}
 
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter ow = db.newObjectInserter();
 		final ObjectId B = commit(ow, treeB, new ObjectId[] {});
 		final ObjectId O = commit(ow, treeO, new ObjectId[] { B });
 		final ObjectId P = commit(ow, treeP, new ObjectId[] { B });
@@ -128,15 +129,17 @@ private void assertCorrectId(final DirCache treeT, final TreeWalk tw) {
 				.getObjectId(0));
 	}
 
-	private ObjectId commit(final ObjectWriter ow, final DirCache treeB,
+	private ObjectId commit(final ObjectInserter odi, final DirCache treeB,
 			final ObjectId[] parentIds) throws Exception {
 		final Commit c = new Commit(db);
-		c.setTreeId(treeB.writeTree(ow));
+		c.setTreeId(treeB.writeTree(odi));
 		c.setAuthor(new PersonIdent("A U Thor", "a.u.thor", 1L, 0));
 		c.setCommitter(c.getAuthor());
 		c.setParentIds(parentIds);
 		c.setMessage("Tree " + c.getTreeId().name());
-		return ow.writeCommit(c);
+		ObjectId id = odi.insert(OBJ_COMMIT, odi.format(c));
+		odi.flush();
+		return id;
 	}
 
 	private DirCacheEntry makeEntry(final String path, final FileMode mode)
@@ -148,9 +151,8 @@ private DirCacheEntry makeEntry(final String path, final FileMode mode,
 			final String content) throws Exception {
 		final DirCacheEntry ent = new DirCacheEntry(path);
 		ent.setFileMode(mode);
-		final byte[] contentBytes = Constants.encode(content);
+		ent.setObjectId(new ObjectInserter.Formatter().idFor(OBJ_BLOB,
-		ent.setObjectId(new ObjectWriter(db).computeBlobSha1(
+				Constants.encode(content)));
-				contentBytes.length, new ByteArrayInputStream(contentBytes)));
 		return ent;
 	}
 }

org.eclipse.jgit.test/tst/org/eclipse/jgit/merge/SimpleMergeTest.java

@@ -44,7 +44,9 @@
 
 package org.eclipse.jgit.merge;
 
-import java.io.ByteArrayInputStream;
+import static org.eclipse.jgit.lib.Constants.OBJ_BLOB;
+import static org.eclipse.jgit.lib.Constants.OBJ_COMMIT;
+
 import java.io.IOException;
 
 import org.eclipse.jgit.dircache.DirCache;
@@ -54,7 +56,7 @@
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectWriter;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.SampleDataRepositoryTestCase;
 import org.eclipse.jgit.treewalk.TreeWalk;
@@ -126,7 +128,7 @@ public void testTrivialTwoWay_validSubtreeSort() throws Exception {
 			t.finish();
 		}
 
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter ow = db.newObjectInserter();
 		final ObjectId b = commit(ow, treeB, new ObjectId[] {});
 		final ObjectId o = commit(ow, treeO, new ObjectId[] { b });
 		final ObjectId t = commit(ow, treeT, new ObjectId[] { b });
@@ -177,7 +179,7 @@ public void testTrivialTwoWay_concurrentSubtreeChange() throws Exception {
 			t.finish();
 		}
 
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter ow = db.newObjectInserter();
 		final ObjectId b = commit(ow, treeB, new ObjectId[] {});
 		final ObjectId o = commit(ow, treeO, new ObjectId[] { b });
 		final ObjectId t = commit(ow, treeT, new ObjectId[] { b });
@@ -224,7 +226,7 @@ public void testTrivialTwoWay_conflictSubtreeChange() throws Exception {
 			t.finish();
 		}
 
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter ow = db.newObjectInserter();
 		final ObjectId b = commit(ow, treeB, new ObjectId[] {});
 		final ObjectId o = commit(ow, treeO, new ObjectId[] { b });
 		final ObjectId t = commit(ow, treeT, new ObjectId[] { b });
@@ -256,7 +258,7 @@ public void testTrivialTwoWay_leftDFconflict1() throws Exception {
 			t.finish();
 		}
 
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter ow = db.newObjectInserter();
 		final ObjectId b = commit(ow, treeB, new ObjectId[] {});
 		final ObjectId o = commit(ow, treeO, new ObjectId[] { b });
 		final ObjectId t = commit(ow, treeT, new ObjectId[] { b });
@@ -288,7 +290,7 @@ public void testTrivialTwoWay_rightDFconflict1() throws Exception {
 			t.finish();
 		}
 
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter ow = db.newObjectInserter();
 		final ObjectId b = commit(ow, treeB, new ObjectId[] {});
 		final ObjectId o = commit(ow, treeO, new ObjectId[] { b });
 		final ObjectId t = commit(ow, treeT, new ObjectId[] { b });
@@ -318,7 +320,7 @@ public void testTrivialTwoWay_leftDFconflict2() throws Exception {
 			t.finish();
 		}
 
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter ow = db.newObjectInserter();
 		final ObjectId b = commit(ow, treeB, new ObjectId[] {});
 		final ObjectId o = commit(ow, treeO, new ObjectId[] { b });
 		final ObjectId t = commit(ow, treeT, new ObjectId[] { b });
@@ -348,7 +350,7 @@ public void testTrivialTwoWay_rightDFconflict2() throws Exception {
 			t.finish();
 		}
 
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter ow = db.newObjectInserter();
 		final ObjectId b = commit(ow, treeB, new ObjectId[] {});
 		final ObjectId o = commit(ow, treeO, new ObjectId[] { b });
 		final ObjectId t = commit(ow, treeT, new ObjectId[] { b });
@@ -363,15 +365,17 @@ private void assertCorrectId(final DirCache treeT, final TreeWalk tw) {
 				.getObjectId(0));
 	}
 
-	private ObjectId commit(final ObjectWriter ow, final DirCache treeB,
+	private ObjectId commit(final ObjectInserter odi, final DirCache treeB,
 			final ObjectId[] parentIds) throws Exception {
 		final Commit c = new Commit(db);
-		c.setTreeId(treeB.writeTree(ow));
+		c.setTreeId(treeB.writeTree(odi));
 		c.setAuthor(new PersonIdent("A U Thor", "a.u.thor", 1L, 0));
 		c.setCommitter(c.getAuthor());
 		c.setParentIds(parentIds);
 		c.setMessage("Tree " + c.getTreeId().name());
-		return ow.writeCommit(c);
+		ObjectId id = odi.insert(OBJ_COMMIT, odi.format(c));
+		odi.flush();
+		return id;
 	}
 
 	private DirCacheEntry makeEntry(final String path, final FileMode mode)
@@ -383,9 +387,8 @@ private DirCacheEntry makeEntry(final String path, final FileMode mode,
 			final String content) throws Exception {
 		final DirCacheEntry ent = new DirCacheEntry(path);
 		ent.setFileMode(mode);
-		final byte[] contentBytes = Constants.encode(content);
+		ent.setObjectId(new ObjectInserter.Formatter().idFor(OBJ_BLOB,
-		ent.setObjectId(new ObjectWriter(db).computeBlobSha1(
+				Constants.encode(content)));
-				contentBytes.length, new ByteArrayInputStream(contentBytes)));
 		return ent;
 	}
 }

org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/filter/PathSuffixFilterTestCase.java

@@ -43,6 +43,8 @@
 
 package org.eclipse.jgit.treewalk.filter;
 
+import static org.eclipse.jgit.lib.Constants.OBJ_BLOB;
+
 import java.io.IOException;
 import java.util.LinkedList;
 import java.util.List;
@@ -52,16 +54,16 @@
 import org.eclipse.jgit.dircache.DirCacheEntry;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectWriter;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.RepositoryTestCase;
 import org.eclipse.jgit.treewalk.TreeWalk;
 
 public class PathSuffixFilterTestCase extends RepositoryTestCase {
 
 	public void testNonRecursiveFiltering() throws IOException {
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter odi = db.newObjectInserter();
-		final ObjectId aSth = ow.writeBlob("a.sth".getBytes());
+		final ObjectId aSth = odi.insert(OBJ_BLOB, "a.sth".getBytes());
-		final ObjectId aTxt = ow.writeBlob("a.txt".getBytes());
+		final ObjectId aTxt = odi.insert(OBJ_BLOB, "a.txt".getBytes());
 		final DirCache dc = DirCache.read(db);
 		final DirCacheBuilder builder = dc.builder();
 		final DirCacheEntry aSthEntry = new DirCacheEntry("a.sth");
@@ -73,7 +75,8 @@ public void testNonRecursiveFiltering() throws IOException {
 		builder.add(aSthEntry);
 		builder.add(aTxtEntry);
 		builder.finish();
-		final ObjectId treeId = dc.writeTree(ow);
+		final ObjectId treeId = dc.writeTree(odi);
+		odi.flush();
 
 
 		final TreeWalk tw = new TreeWalk(db);
@@ -92,11 +95,11 @@ public void testNonRecursiveFiltering() throws IOException {
 	}
 
 	public void testRecursiveFiltering() throws IOException {
-		final ObjectWriter ow = new ObjectWriter(db);
+		final ObjectInserter odi = db.newObjectInserter();
-		final ObjectId aSth = ow.writeBlob("a.sth".getBytes());
+		final ObjectId aSth = odi.insert(OBJ_BLOB, "a.sth".getBytes());
-		final ObjectId aTxt = ow.writeBlob("a.txt".getBytes());
+		final ObjectId aTxt = odi.insert(OBJ_BLOB, "a.txt".getBytes());
-		final ObjectId bSth = ow.writeBlob("b.sth".getBytes());
+		final ObjectId bSth = odi.insert(OBJ_BLOB, "b.sth".getBytes());
-		final ObjectId bTxt = ow.writeBlob("b.txt".getBytes());
+		final ObjectId bTxt = odi.insert(OBJ_BLOB, "b.txt".getBytes());
 		final DirCache dc = DirCache.read(db);
 		final DirCacheBuilder builder = dc.builder();
 		final DirCacheEntry aSthEntry = new DirCacheEntry("a.sth");
@@ -116,7 +119,8 @@ public void testRecursiveFiltering() throws IOException {
 		builder.add(bSthEntry);
 		builder.add(bTxtEntry);
 		builder.finish();
-		final ObjectId treeId = dc.writeTree(ow);
+		final ObjectId treeId = dc.writeTree(odi);
+		odi.flush();
 
 
 		final TreeWalk tw = new TreeWalk(db);

org.eclipse.jgit/src/org/eclipse/jgit/api/CommitCommand.java

@@ -54,13 +54,13 @@
 import org.eclipse.jgit.lib.Commit;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectWriter;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.PersonIdent;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.RefUpdate;
-import org.eclipse.jgit.lib.RefUpdate.Result;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.lib.RepositoryState;
+import org.eclipse.jgit.lib.RefUpdate.Result;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevWalk;
 
@@ -141,52 +141,59 @@ public RevCommit call() throws NoHeadException, NoMessageException,
 			// lock the index
 			DirCache index = DirCache.lock(repo);
 			try {
-				ObjectWriter repoWriter = new ObjectWriter(repo);
+				ObjectInserter odi = repo.newObjectInserter();
+				try {
+					// Write the index as tree to the object database. This may
+					// fail for example when the index contains unmerged paths
+					// (unresolved conflicts)
+					ObjectId indexTreeId = index.writeTree(odi);
 
-				// Write the index as tree to the object database. This may fail
+					// Create a Commit object, populate it and write it
-				// for example when the index contains unmerged pathes
+					Commit commit = new Commit(repo);
-				// (unresolved conflicts)
+					commit.setCommitter(committer);
-				ObjectId indexTreeId = index.writeTree(repoWriter);
+					commit.setAuthor(author);
+					commit.setMessage(message);
 
-				// Create a Commit object, populate it and write it
+					commit.setParentIds(parents.toArray(new ObjectId[] {}));
-				Commit commit = new Commit(repo);
+					commit.setTreeId(indexTreeId);
-				commit.setCommitter(committer);
+					ObjectId commitId = odi.insert(Constants.OBJ_COMMIT, odi
-				commit.setAuthor(author);
+							.format(commit));
-				commit.setMessage(message);
+					odi.flush();
 
-				commit.setParentIds(parents.toArray(new ObjectId[]{}));
+					RevCommit revCommit = new RevWalk(repo)
-				commit.setTreeId(indexTreeId);
+							.parseCommit(commitId);
-				ObjectId commitId = repoWriter.writeCommit(commit);
+					RefUpdate ru = repo.updateRef(Constants.HEAD);
+					ru.setNewObjectId(commitId);
+					ru.setRefLogMessage("commit : "
+							+ revCommit.getShortMessage(), false);
 
-				RevCommit revCommit = new RevWalk(repo).parseCommit(commitId);
+					ru.setExpectedOldObjectId(headId);
-				RefUpdate ru = repo.updateRef(Constants.HEAD);
+					Result rc = ru.update();
-				ru.setNewObjectId(commitId);
+					switch (rc) {
-				ru.setRefLogMessage("commit : " + revCommit.getShortMessage(),
+					case NEW:
-						false);
+					case FAST_FORWARD:
-
+						setCallable(false);
-				ru.setExpectedOldObjectId(headId);
+						if (state == RepositoryState.MERGING_RESOLVED) {
-				Result rc = ru.update();
+							// Commit was successful. Now delete the files
-				switch (rc) {
+							// used for merge commits
-				case NEW:
+							new File(repo.getDirectory(), Constants.MERGE_HEAD)
-				case FAST_FORWARD:
+									.delete();
-					setCallable(false);
+							new File(repo.getDirectory(), Constants.MERGE_MSG)
-					if (state == RepositoryState.MERGING_RESOLVED) {
+									.delete();
-						// Commit was successful. Now delete the files
+						}
-						// used for merge commits
+						return revCommit;
-						new File(repo.getDirectory(), Constants.MERGE_HEAD)
+					case REJECTED:
-								.delete();
+					case LOCK_FAILURE:
-						new File(repo.getDirectory(), Constants.MERGE_MSG)
+						throw new ConcurrentRefUpdateException(
-								.delete();
+								JGitText.get().couldNotLockHEAD, ru.getRef(),
+								rc);
+					default:
+						throw new JGitInternalException(MessageFormat.format(
+								JGitText.get().updatingRefFailed,
+								Constants.HEAD, commitId.toString(), rc));
 					}
-					return revCommit;
+				} finally {
-				case REJECTED:
+					odi.release();
-				case LOCK_FAILURE:
-					throw new ConcurrentRefUpdateException(
-							JGitText.get().couldNotLockHEAD, ru.getRef(), rc);
-				default:
-					throw new JGitInternalException(MessageFormat.format(
-							JGitText.get().updatingRefFailed
-							, Constants.HEAD, commitId.toString(), rc));
 				}
 			} finally {
 				index.unlock();

org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCache.java

@@ -66,7 +66,7 @@
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.LockFile;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectWriter;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.util.IO;
 import org.eclipse.jgit.util.MutableInteger;
@@ -772,7 +772,9 @@ public DirCacheTree getCacheTree(final boolean build) {
 	 * Write all index trees to the object store, returning the root tree.
 	 *
 	 * @param ow
-	 *            the writer to use when serializing to the store.
+	 *            the writer to use when serializing to the store. The caller is
+	 *            responsible for flushing the inserter before trying to use the
+	 *            returned tree identity.
 	 * @return identity for the root tree.
 	 * @throws UnmergedPathException
 	 *             one or more paths contain higher-order stages (stage > 0),
@@ -783,7 +785,7 @@ public DirCacheTree getCacheTree(final boolean build) {
 	 * @throws IOException
 	 *             an unexpected error occurred writing to the object store.
 	 */
-	public ObjectId writeTree(final ObjectWriter ow)
+	public ObjectId writeTree(final ObjectInserter ow)
 			throws UnmergedPathException, IOException {
 		return getCacheTree(true).writeTree(sortedEntries, 0, 0, ow);
 	}

org.eclipse.jgit/src/org/eclipse/jgit/dircache/DirCacheTree.java

@@ -57,7 +57,7 @@
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectWriter;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.util.MutableInteger;
 import org.eclipse.jgit.util.RawParseUtils;
 
@@ -311,7 +311,7 @@ public String getPathString() {
 	 *             an unexpected error occurred writing to the object store.
 	 */
 	ObjectId writeTree(final DirCacheEntry[] cache, int cIdx,
-			final int pathOffset, final ObjectWriter ow)
+			final int pathOffset, final ObjectInserter ow)
 			throws UnmergedPathException, IOException {
 		if (id == null) {
 			final int endIdx = cIdx + entrySpan;
@@ -346,13 +346,13 @@ ObjectId writeTree(final DirCacheEntry[] cache, int cIdx,
 				entryIdx++;
 			}
 
-			id = ow.writeCanonicalTree(out.toByteArray());
+			id = ow.insert(Constants.OBJ_TREE, out.toByteArray());
 		}
 		return id;
 	}
 
 	private int computeSize(final DirCacheEntry[] cache, int cIdx,
-			final int pathOffset, final ObjectWriter ow)
+			final int pathOffset, final ObjectInserter ow)
 			throws UnmergedPathException, IOException {
 		final int endIdx = cIdx + entrySpan;
 		int childIdx = 0;

org.eclipse.jgit/src/org/eclipse/jgit/lib/Commit.java

@@ -339,7 +339,14 @@ public void setMessage(final String m) {
 	public void commit() throws IOException {
 		if (getCommitId() != null)
 			throw new IllegalStateException(MessageFormat.format(JGitText.get().commitAlreadyExists, getCommitId()));
-		setCommitId(new ObjectWriter(objdb).writeCommit(this));
+		ObjectInserter odi = objdb.getObjectDatabase().newInserter();
+		try {
+			ObjectId id = odi.insert(Constants.OBJ_COMMIT, odi.format(this));
+			odi.flush();
+			setCommitId(id);
+		} finally {
+			odi.release();
+		}
 	}
 
 	public String toString() {

org.eclipse.jgit/src/org/eclipse/jgit/lib/Tag.java

@@ -203,9 +203,14 @@ public void tag() throws IOException {
 		final RefUpdate ru;
 
 		if (tagger!=null || message!=null || type!=null) {
-			ObjectId tagid = new ObjectWriter(objdb).writeTag(this);
+			ObjectInserter odi = objdb.newObjectInserter();
-			setTagId(tagid);
+			try {
-			id = tagid;
+				id = odi.insert(Constants.OBJ_TAG, odi.format(this));
+				odi.flush();
+				setTagId(id);
+			} finally {
+				odi.release();
+			}
 		} else {
 			id = objId;
 		}

org.eclipse.jgit/src/org/eclipse/jgit/merge/Merger.java

@@ -51,7 +51,7 @@
 import org.eclipse.jgit.lib.AnyObjectId;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
-import org.eclipse.jgit.lib.ObjectWriter;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.lib.WindowCursor;
 import org.eclipse.jgit.revwalk.RevCommit;
@@ -73,7 +73,7 @@ public abstract class Merger {
 	/** A RevWalk for computing merge bases, or listing incoming commits. */
 	protected final RevWalk walk;
 
-	private ObjectWriter writer;
+	private ObjectInserter inserter;
 
 	/** The original objects supplied in the merge; this can be any tree-ish. */
 	protected RevObject[] sourceObjects;
@@ -105,10 +105,10 @@ public Repository getRepository() {
 	/**
 	 * @return an object writer to create objects in {@link #getRepository()}.
 	 */
-	public ObjectWriter getObjectWriter() {
+	public ObjectInserter getObjectInserter() {
-		if (writer == null)
+		if (inserter == null)
-			writer = new ObjectWriter(getRepository());
+			inserter = getRepository().newObjectInserter();
-		return writer;
+		return inserter;
 	}
 
 	/**

org.eclipse.jgit/src/org/eclipse/jgit/merge/StrategySimpleTwoWayInCore.java

@@ -51,6 +51,7 @@
 import org.eclipse.jgit.errors.UnmergedPathException;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.treewalk.AbstractTreeIterator;
 import org.eclipse.jgit.treewalk.NameConflictTreeWalk;
@@ -152,7 +153,16 @@ else if (tw.isSubtree()) {
 			if (hasConflict)
 				return false;
 			try {
-				resultTree = cache.writeTree(getObjectWriter());
+				ObjectInserter odi = getObjectInserter();
+				try {
+					resultTree = cache.writeTree(odi);
+					odi.flush();
+				} finally {
+					// We don't know if our caller will release the
+					// inserter, so make sure we do it ourselves.
+					//
+					odi.release();
+				}
 				return true;
 			} catch (UnmergedPathException upe) {
 				resultTree = null;