Replace deprecated release() methods by close()

See the discussion [1] in the Gerrit mailing list.

[1] https://groups.google.com/forum/#!topic/repo-discuss/RRQT_xCqz4o

Change-Id: I2c67384309c5c2e8511a7d0d4e088b4e95f819ff
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

30 files changed, 313 insertions, 385 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CloneCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CloneCommandTest.java
index ea07beed70..3b2fa6c37d 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CloneCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CloneCommandTest.java
@@ -414,17 +414,19 @@ public class CloneCommandTest extends RepositoryTestCase {
 		assertEquals(commit, pathStatus.getHeadId());
 		assertEquals(commit, pathStatus.getIndexId());
 
-		SubmoduleWalk walk = SubmoduleWalk.forIndex(git2.getRepository());
-		assertTrue(walk.next());
-		Repository clonedSub1 = walk.getRepository();
-		addRepoToClose(clonedSub1);
-		assertNotNull(clonedSub1);
-		assertEquals(
-				new File(git2.getRepository().getWorkTree(), walk.getPath()),
-				clonedSub1.getWorkTree());
-		assertEquals(new File(new File(git2.getRepository().getDirectory(),
-				"modules"), walk.getPath()), clonedSub1.getDirectory());
-		walk.release();
+		try (SubmoduleWalk walk = SubmoduleWalk
+				.forIndex(git2.getRepository())) {
+			assertTrue(walk.next());
+			Repository clonedSub1 = walk.getRepository();
+			addRepoToClose(clonedSub1);
+			assertNotNull(clonedSub1);
+			assertEquals(new File(git2.getRepository().getWorkTree(),
+					walk.getPath()), clonedSub1.getWorkTree());
+			assertEquals(
+					new File(new File(git2.getRepository().getDirectory(),
+							"modules"), walk.getPath()),
+					clonedSub1.getDirectory());
+		}
 	}
 
 	@Test
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CommitCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CommitCommandTest.java
index 1f71402879..2c70a166e3 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CommitCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CommitCommandTest.java
@@ -509,9 +509,9 @@ public class CommitCommandTest extends RepositoryTestCase {
 				+ "[unmerged2, mode:100644, stage:3]",
 				indexState(0));
 
-		TreeWalk walk = TreeWalk.forPath(db, "unmerged1", commit.getTree());
-		assertEquals(FileMode.REGULAR_FILE, walk.getFileMode(0));
-		walk.release();
+		try (TreeWalk walk = TreeWalk.forPath(db, "unmerged1", commit.getTree())) {
+			assertEquals(FileMode.REGULAR_FILE, walk.getFileMode(0));
+		}
 	}
 
 	private static void addUnmergedEntry(String file, DirCacheBuilder builder) {
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/DiffCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/DiffCommandTest.java
index c5608b3f1e..4ad01cf6f0 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/DiffCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/DiffCommandTest.java
@@ -247,12 +247,9 @@ public class DiffCommandTest extends RepositoryTestCase {
 		if (id == null)
 			throw new IllegalArgumentException(name);
 		final CanonicalTreeParser p = new CanonicalTreeParser();
-		final ObjectReader or = db.newObjectReader();
-		try {
+		try (ObjectReader or = db.newObjectReader()) {
 			p.reset(or, new RevWalk(db).parseTree(id));
 			return p;
-		} finally {
-			or.release();
 		}
 	}
 }
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PathCheckoutCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PathCheckoutCommandTest.java
index eb092ad6c8..db811cdf59 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PathCheckoutCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PathCheckoutCommandTest.java
@@ -193,8 +193,8 @@ public class PathCheckoutCommandTest extends RepositoryTestCase {
 	public static void validateIndex(Git git) throws NoWorkTreeException,
 			IOException {
 		DirCache dc = git.getRepository().lockDirCache();
-		ObjectReader r = git.getRepository().getObjectDatabase().newReader();
-		try {
+		try (ObjectReader r = git.getRepository().getObjectDatabase()
+				.newReader()) {
 			for (int i = 0; i < dc.getEntryCount(); ++i) {
 				DirCacheEntry entry = dc.getEntry(i);
 				if (entry.getLength() > 0)
@@ -203,7 +203,6 @@ public class PathCheckoutCommandTest extends RepositoryTestCase {
 			}
 		} finally {
 			dc.unlock();
-			r.release();
 		}
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PullCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PullCommandTest.java
index d4805d0aa1..57888e70a8 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PullCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PullCommandTest.java
@@ -474,34 +474,35 @@ public class PullCommandTest extends RepositoryTestCase {
 		}
 		assertFileContentsEqual(sourceFile, "content");
 
-		RevWalk rw = new RevWalk(dbTarget);
-		rw.sort(RevSort.TOPO);
-		rw.markStart(rw.parseCommit(dbTarget.resolve("refs/heads/master")));
+		try (RevWalk rw = new RevWalk(dbTarget)) {
+			rw.sort(RevSort.TOPO);
+			rw.markStart(rw.parseCommit(dbTarget.resolve("refs/heads/master")));
 
-		RevCommit next;
-		if (expectedPullMode == TestPullMode.MERGE) {
-			next = rw.next();
-			assertEquals(2, next.getParentCount());
-			assertEquals(merge, next.getParent(0));
-			assertEquals(sourceCommit, next.getParent(1));
-			// since both parents are known do no further checks here
-		} else {
-			if (expectedPullMode == TestPullMode.REBASE_PREASERVE) {
+			RevCommit next;
+			if (expectedPullMode == TestPullMode.MERGE) {
 				next = rw.next();
 				assertEquals(2, next.getParentCount());
+				assertEquals(merge, next.getParent(0));
+				assertEquals(sourceCommit, next.getParent(1));
+				// since both parents are known do no further checks here
+			} else {
+				if (expectedPullMode == TestPullMode.REBASE_PREASERVE) {
+					next = rw.next();
+					assertEquals(2, next.getParentCount());
+				}
+				next = rw.next();
+				assertEquals(t2.getShortMessage(), next.getShortMessage());
+				next = rw.next();
+				assertEquals(t1.getShortMessage(), next.getShortMessage());
+				next = rw.next();
+				assertEquals(sourceCommit, next);
+				next = rw.next();
+				assertEquals("Initial commit for source",
+						next.getShortMessage());
+				next = rw.next();
+				assertNull(next);
 			}
-			next = rw.next();
-			assertEquals(t2.getShortMessage(), next.getShortMessage());
-			next = rw.next();
-			assertEquals(t1.getShortMessage(), next.getShortMessage());
-			next = rw.next();
-			assertEquals(sourceCommit, next);
-			next = rw.next();
-			assertEquals("Initial commit for source", next.getShortMessage());
-			next = rw.next();
-			assertNull(next);
 		}
-		rw.release();
 	}
 
 	@Override
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/RebaseCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/RebaseCommandTest.java
index 6b641c495f..8b0ed5f39d 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/RebaseCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/RebaseCommandTest.java
@@ -114,13 +114,14 @@ public class RebaseCommandTest extends RepositoryTestCase {
 
 	private void checkoutCommit(RevCommit commit) throws IllegalStateException,
 			IOException {
-		RevWalk walk = new RevWalk(db);
-		RevCommit head = walk.parseCommit(db.resolve(Constants.HEAD));
-		DirCacheCheckout dco = new DirCacheCheckout(db, head.getTree(), db
-				.lockDirCache(), commit.getTree());
-		dco.setFailOnConflict(true);
-		dco.checkout();
-		walk.release();
+		RevCommit head;
+		try (RevWalk walk = new RevWalk(db)) {
+			head = walk.parseCommit(db.resolve(Constants.HEAD));
+			DirCacheCheckout dco = new DirCacheCheckout(db, head.getTree(),
+					db.lockDirCache(), commit.getTree());
+			dco.setFailOnConflict(true);
+			dco.checkout();
+		}
 		// update the HEAD
 		RefUpdate refUpdate = db.updateRef(Constants.HEAD, true);
 		refUpdate.setNewObjectId(commit);
@@ -472,11 +473,12 @@ public class RebaseCommandTest extends RepositoryTestCase {
 	}
 
 	private String readFile(String path, RevCommit commit) throws IOException {
-		TreeWalk walk = TreeWalk.forPath(db, path, commit.getTree());
-		ObjectLoader loader = db.open(walk.getObjectId(0), Constants.OBJ_BLOB);
-		String result = RawParseUtils.decode(loader.getCachedBytes());
-		walk.release();
-		return result;
+		try (TreeWalk walk = TreeWalk.forPath(db, path, commit.getTree())) {
+			ObjectLoader loader = db.open(walk.getObjectId(0),
+					Constants.OBJ_BLOB);
+			String result = RawParseUtils.decode(loader.getCachedBytes());
+			return result;
+		}
 	}
 
 	@Test
@@ -2073,14 +2075,11 @@ public class RebaseCommandTest extends RepositoryTestCase {
 	private List<DiffEntry> diffWorkingAgainstHead(final RevCommit commit,
 			RevWalk revWalk)
 			throws IOException {
-		TreeWalk walk = createTreeWalk();
 		RevCommit parentCommit = revWalk.parseCommit(commit.getParent(0));
-		try {
+		try (TreeWalk walk = createTreeWalk()) {
 			walk.addTree(parentCommit.getTree());
 			walk.addTree(commit.getTree());
 			return DiffEntry.scan(walk);
-		} finally {
-			walk.release();
 		}
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/ResetCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/ResetCommandTest.java
index c48b412401..9997c8c426 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/ResetCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/ResetCommandTest.java
@@ -537,16 +537,10 @@ public class ResetCommandTest extends RepositoryTestCase {
 	 */
 	private boolean inHead(String path) throws IOException {
 		ObjectId headId = db.resolve(Constants.HEAD);
-		RevWalk rw = new RevWalk(db);
-		TreeWalk tw = null;
-		try {
-			tw = TreeWalk.forPath(db, path, rw.parseTree(headId));
+		try (RevWalk rw = new RevWalk(db);
+				TreeWalk tw = TreeWalk.forPath(db, path,
+						rw.parseTree(headId))) {
 			return tw != null;
-		} finally {
-			rw.release();
-			rw.dispose();
-			if (tw != null)
-				tw.release();
 		}
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java
index 387120342f..c317e3beef 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/StashCreateCommandTest.java
@@ -118,12 +118,9 @@ public class StashCreateCommandTest extends RepositoryTestCase {
 		assertEquals(parentCount, commit.getParentCount());
 
 		// Load parents
-		RevWalk walk = new RevWalk(db);
-		try {
+		try (RevWalk walk = new RevWalk(db)) {
 			for (RevCommit parent : commit.getParents())
 				walk.parseBody(parent);
-		} finally {
-			walk.release();
 		}
 
 		assertEquals(1, commit.getParent(1).getParentCount());
@@ -144,37 +141,28 @@ public class StashCreateCommandTest extends RepositoryTestCase {
 
 	private List<DiffEntry> diffWorkingAgainstHead(final RevCommit commit)
 			throws IOException {
-		TreeWalk walk = createTreeWalk();
-		try {
+		try (TreeWalk walk = createTreeWalk()) {
 			walk.addTree(commit.getParent(0).getTree());
 			walk.addTree(commit.getTree());
 			return DiffEntry.scan(walk);
-		} finally {
-			walk.release();
 		}
 	}
 
 	private List<DiffEntry> diffIndexAgainstHead(final RevCommit commit)
 			throws IOException {
-		TreeWalk walk = createTreeWalk();
-		try {
+		try (TreeWalk walk = createTreeWalk()) {
 			walk.addTree(commit.getParent(0).getTree());
 			walk.addTree(commit.getParent(1).getTree());
 			return DiffEntry.scan(walk);
-		} finally {
-			walk.release();
 		}
 	}
 
 	private List<DiffEntry> diffIndexAgainstWorking(final RevCommit commit)
 			throws IOException {
-		TreeWalk walk = createTreeWalk();
-		try {
+		try (TreeWalk walk = createTreeWalk()) {
 			walk.addTree(commit.getParent(1).getTree());
 			walk.addTree(commit.getTree());
 			return DiffEntry.scan(walk);
-		} finally {
-			walk.release();
 		}
 	}
 
@@ -224,11 +212,12 @@ public class StashCreateCommandTest extends RepositoryTestCase {
 		writeTrashFile("file", "content2");
 		RevCommit stashedWorkTree = Git.wrap(db).stashCreate().call();
 		validateStashedCommit(stashedWorkTree);
-		RevWalk walk = new RevWalk(db);
-		RevCommit stashedIndex = stashedWorkTree.getParent(1);
-		walk.parseBody(stashedIndex);
-		walk.parseBody(stashedIndex.getTree());
-		walk.parseBody(stashedIndex.getParent(0));
+		try (RevWalk walk = new RevWalk(db)) {
+			RevCommit stashedIndex = stashedWorkTree.getParent(1);
+			walk.parseBody(stashedIndex);
+			walk.parseBody(stashedIndex.getTree());
+			walk.parseBody(stashedIndex.getParent(0));
+		}
 		List<DiffEntry> workTreeStashAgainstWorkTree = diffWorkingAgainstHead(stashedWorkTree);
 		assertEquals(1, workTreeStashAgainstWorkTree.size());
 		List<DiffEntry> workIndexAgainstWorkTree = diffIndexAgainstHead(stashedWorkTree);
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/blame/BlameGeneratorTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/blame/BlameGeneratorTest.java
index a7bce1e11e..42909f0d76 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/blame/BlameGeneratorTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/blame/BlameGeneratorTest.java
@@ -70,8 +70,7 @@ public class BlameGeneratorTest extends RepositoryTestCase {
 		git.add().addFilepattern("file.txt").call();
 		RevCommit c2 = git.commit().setMessage("create file").call();
 
-		BlameGenerator generator = new BlameGenerator(db, "file.txt");
-		try {
+		try (BlameGenerator generator = new BlameGenerator(db, "file.txt")) {
 			generator.push(null, db.resolve(Constants.HEAD));
 			assertEquals(3, generator.getResultContents().size());
 
@@ -94,8 +93,6 @@ public class BlameGeneratorTest extends RepositoryTestCase {
 			assertEquals("file.txt", generator.getSourcePath());
 
 			assertFalse(generator.next());
-		} finally {
-			generator.release();
 		}
 	}
 
@@ -123,8 +120,7 @@ public class BlameGeneratorTest extends RepositoryTestCase {
 		git.add().addFilepattern(FILENAME_2).call();
 		RevCommit c2 = git.commit().setMessage("change file2").call();
 
-		BlameGenerator generator = new BlameGenerator(db, FILENAME_2);
-		try {
+		try (BlameGenerator generator = new BlameGenerator(db, FILENAME_2)) {
 			generator.push(null, db.resolve(Constants.HEAD));
 			assertEquals(3, generator.getResultContents().size());
 
@@ -147,13 +143,10 @@ public class BlameGeneratorTest extends RepositoryTestCase {
 			assertEquals(FILENAME_1, generator.getSourcePath());
 
 			assertFalse(generator.next());
-		} finally {
-			generator.release();
 		}
 
 		// and test again with other BlameGenerator API:
-		generator = new BlameGenerator(db, FILENAME_2);
-		try {
+		try (BlameGenerator generator = new BlameGenerator(db, FILENAME_2)) {
 			generator.push(null, db.resolve(Constants.HEAD));
 			BlameResult result = generator.computeBlameResult();
 
@@ -167,9 +160,6 @@ public class BlameGeneratorTest extends RepositoryTestCase {
 
 			assertEquals(c1, result.getSourceCommit(2));
 			assertEquals(FILENAME_1, result.getSourcePath(2));
-
-		} finally {
-			generator.release();
 		}
 	}
 
@@ -193,8 +183,7 @@ public class BlameGeneratorTest extends RepositoryTestCase {
 		git.add().addFilepattern("file.txt").call();
 		RevCommit c3 = git.commit().setMessage("create file").call();
 
-		BlameGenerator generator = new BlameGenerator(db, "file.txt");
-		try {
+		try (BlameGenerator generator = new BlameGenerator(db, "file.txt")) {
 			generator.push(null, db.resolve(Constants.HEAD));
 			assertEquals(3, generator.getResultContents().size());
 
@@ -204,8 +193,6 @@ public class BlameGeneratorTest extends RepositoryTestCase {
 			assertEquals(3, generator.getResultEnd());
 
 			assertFalse(generator.next());
-		} finally {
-			generator.release();
 		}
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffFormatterTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffFormatterTest.java
index 91498e7dfc..02e485d41e 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffFormatterTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/diff/DiffFormatterTest.java
@@ -98,8 +98,9 @@ public class DiffFormatterTest extends RepositoryTestCase {
 	@Override
 	@After
 	public void tearDown() throws Exception {
-		if (df != null)
-			df.release();
+		if (df != null) {
+			df.close();
+		}
 		super.tearDown();
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/dfs/DfsInserterTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/dfs/DfsInserterTest.java
index 693388c0bf..fc8cbaa437 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/dfs/DfsInserterTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/dfs/DfsInserterTest.java
@@ -78,12 +78,11 @@ public class DfsInserterTest {
 
 	@Test
 	public void testInserterDiscardsPack() throws IOException {
-		ObjectInserter ins = db.newObjectInserter();
-		ins.insert(Constants.OBJ_BLOB, Constants.encode("foo"));
-		ins.insert(Constants.OBJ_BLOB, Constants.encode("bar"));
-		assertEquals(0, db.getObjectDatabase().listPacks().size());
-
-		ins.release();
+		try (ObjectInserter ins = db.newObjectInserter()) {
+			ins.insert(Constants.OBJ_BLOB, Constants.encode("foo"));
+			ins.insert(Constants.OBJ_BLOB, Constants.encode("bar"));
+			assertEquals(0, db.getObjectDatabase().listPacks().size());
+		}
 		assertEquals(0, db.getObjectDatabase().listPacks().size());
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/AbbreviationTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/AbbreviationTest.java
index 3a0b827b3f..987540399b 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/AbbreviationTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/AbbreviationTest.java
@@ -94,8 +94,9 @@ public class AbbreviationTest extends LocalDiskRepositoryTestCase {
 
 	@After
 	public void tearDown() throws Exception {
-		if (reader != null)
-			reader.release();
+		if (reader != null) {
+			reader.close();
+		}
 	}
 
 	@Test
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/ConcurrentRepackTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/ConcurrentRepackTest.java
index 562cde72ca..514e00f356 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/ConcurrentRepackTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/ConcurrentRepackTest.java
@@ -150,11 +150,11 @@ public class ConcurrentRepackTest extends RepositoryTestCase {
 		// within the pack has been modified.
 		//
 		final RevObject o2 = writeBlob(eden, "o2");
-		final PackWriter pw = new PackWriter(eden);
-		pw.addObject(o2);
-		pw.addObject(o1);
-		write(out1, pw);
-		pw.release();
+		try (PackWriter pw = new PackWriter(eden)) {
+			pw.addObject(o2);
+			pw.addObject(o1);
+			write(out1, pw);
+		}
 
 		// Try the old name, then the new name. The old name should cause the
 		// pack to reload when it opens and the index and pack mismatch.
@@ -216,18 +216,18 @@ public class ConcurrentRepackTest extends RepositoryTestCase {
 
 	private File[] pack(final Repository src, final RevObject... list)
 			throws IOException {
-		final PackWriter pw = new PackWriter(src);
-		for (final RevObject o : list) {
-			pw.addObject(o);
-		}
+		try (PackWriter pw = new PackWriter(src)) {
+			for (final RevObject o : list) {
+				pw.addObject(o);
+			}
 
-		final ObjectId name = pw.computeName();
-		final File packFile = fullPackFileName(name, ".pack");
-		final File idxFile = fullPackFileName(name, ".idx");
-		final File[] files = new File[] { packFile, idxFile };
-		write(files, pw);
-		pw.release();
-		return files;
+			final ObjectId name = pw.computeName();
+			final File packFile = fullPackFileName(name, ".pack");
+			final File idxFile = fullPackFileName(name, ".idx");
+			final File[] files = new File[] { packFile, idxFile };
+			write(files, pw);
+			return files;
+		}
 	}
 
 	private static void write(final File[] files, final PackWriter pw)
@@ -282,13 +282,10 @@ public class ConcurrentRepackTest extends RepositoryTestCase {
 			throws IOException {
 		final RevWalk revWalk = new RevWalk(repo);
 		final byte[] bytes = Constants.encode(data);
-		final ObjectInserter inserter = repo.newObjectInserter();
 		final ObjectId id;
-		try {
+		try (ObjectInserter inserter = repo.newObjectInserter()) {
 			id = inserter.insert(Constants.OBJ_BLOB, bytes);
 			inserter.flush();
-		} finally {
-			inserter.release();
 		}
 		try {
 			parse(id);
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackFileTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackFileTest.java
index 3324627e7f..05055644ec 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackFileTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackFileTest.java
@@ -373,8 +373,9 @@ public class PackFileTest extends LocalDiskRepositoryTestCase {
 
 	@After
 	public void release() {
-		if (inserter != null)
-			inserter.release();
+		if (inserter != null) {
+			inserter.close();
+		}
 	}
 
 	private PackParser index(byte[] raw) throws IOException {
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackWriterTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackWriterTest.java
index 873b2cda45..bc880a13ef 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackWriterTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/PackWriterTest.java
@@ -120,11 +120,11 @@ public class PackWriterTest extends SampleDataRepositoryTestCase {
 	@After
 	public void tearDown() throws Exception {
 		if (writer != null) {
-			writer.release();
+			writer.close();
 			writer = null;
 		}
 		if (inserter != null) {
-			inserter.release();
+			inserter.close();
 			inserter = null;
 		}
 		super.tearDown();
@@ -514,26 +514,26 @@ public class PackWriterTest extends SampleDataRepositoryTestCase {
 	private static PackIndex writePack(FileRepository repo,
 			Set<? extends ObjectId> want, Set<ObjectIdSet> excludeObjects)
 			throws IOException {
-		PackWriter pw = new PackWriter(repo);
-		pw.setDeltaBaseAsOffset(true);
-		pw.setReuseDeltaCommits(false);
-		for (ObjectIdSet idx : excludeObjects)
-			pw.excludeObjects(idx);
-		pw.preparePack(NullProgressMonitor.INSTANCE, want,
-				Collections.<ObjectId> emptySet());
-		String id = pw.computeName().getName();
-		File packdir = new File(repo.getObjectsDirectory(), "pack");
-		File packFile = new File(packdir, "pack-" + id + ".pack");
-		FileOutputStream packOS = new FileOutputStream(packFile);
-		pw.writePack(NullProgressMonitor.INSTANCE,
-				NullProgressMonitor.INSTANCE, packOS);
-		packOS.close();
-		File idxFile = new File(packdir, "pack-" + id + ".idx");
-		FileOutputStream idxOS = new FileOutputStream(idxFile);
-		pw.writeIndex(idxOS);
-		idxOS.close();
-		pw.release();
-		return PackIndex.open(idxFile);
+		try (PackWriter pw = new PackWriter(repo)) {
+			pw.setDeltaBaseAsOffset(true);
+			pw.setReuseDeltaCommits(false);
+			for (ObjectIdSet idx : excludeObjects)
+				pw.excludeObjects(idx);
+			pw.preparePack(NullProgressMonitor.INSTANCE, want,
+					Collections.<ObjectId> emptySet());
+			String id = pw.computeName().getName();
+			File packdir = new File(repo.getObjectsDirectory(), "pack");
+			File packFile = new File(packdir, "pack-" + id + ".pack");
+			FileOutputStream packOS = new FileOutputStream(packFile);
+			pw.writePack(NullProgressMonitor.INSTANCE,
+					NullProgressMonitor.INSTANCE, packOS);
+			packOS.close();
+			File idxFile = new File(packdir, "pack-" + id + ".idx");
+			FileOutputStream idxOS = new FileOutputStream(idxFile);
+			pw.writeIndex(idxOS);
+			idxOS.close();
+			return PackIndex.open(idxFile);
+		}
 	}
 
 	// TODO: testWritePackDeltasCycle()
@@ -639,7 +639,7 @@ public class PackWriterTest extends SampleDataRepositoryTestCase {
 		writer.setIgnoreMissingUninteresting(ignoreMissingUninteresting);
 		writer.preparePack(m, interestings, uninterestings);
 		writer.writePack(m, m, os);
-		writer.release();
+		writer.close();
 		verifyOpenPack(thin);
 	}
 
@@ -650,7 +650,7 @@ public class PackWriterTest extends SampleDataRepositoryTestCase {
 		writer.preparePack(objectSource.iterator());
 		assertEquals(objectSource.size(), writer.getObjectCount());
 		writer.writePack(m, m, os);
-		writer.release();
+		writer.close();
 		verifyOpenPack(false);
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/T0003_BasicTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/T0003_BasicTest.java
index 0ab013baff..5670a9634d 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/T0003_BasicTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/internal/storage/file/T0003_BasicTest.java
@@ -304,11 +304,12 @@ public class T0003_BasicTest extends SampleDataRepositoryTestCase {
 		// object (as it already exists in the pack).
 		//
 		final Repository newdb = createBareRepository();
-		final ObjectInserter oi = newdb.newObjectInserter();
-		final ObjectId treeId = oi.insert(new TreeFormatter());
-		oi.release();
+		try (final ObjectInserter oi = newdb.newObjectInserter()) {
+			final ObjectId treeId = oi.insert(new TreeFormatter());
+			assertEquals("4b825dc642cb6eb9a060e54bf8d69288fbee4904",
+					treeId.name());
+		}
 
-		assertEquals("4b825dc642cb6eb9a060e54bf8d69288fbee4904", treeId.name());
 		final File o = new File(new File(new File(newdb.getDirectory(),
 				"objects"), "4b"), "825dc642cb6eb9a060e54bf8d69288fbee4904");
 		assertTrue("Exists " + o, o.isFile());
@@ -569,8 +570,7 @@ public class T0003_BasicTest extends SampleDataRepositoryTestCase {
 	@Test
 	public void test026_CreateCommitMultipleparents() throws IOException {
 		final ObjectId treeId;
-		final ObjectInserter oi = db.newObjectInserter();
-		try {
+		try (final ObjectInserter oi = db.newObjectInserter()) {
 			final ObjectId blobId = oi.insert(Constants.OBJ_BLOB,
 					"and this is the data in me\n".getBytes(Constants.CHARSET
 							.name()));
@@ -578,8 +578,6 @@ public class T0003_BasicTest extends SampleDataRepositoryTestCase {
 			fmt.append("i-am-a-file", FileMode.REGULAR_FILE, blobId);
 			treeId = oi.insert(fmt);
 			oi.flush();
-		} finally {
-			oi.release();
 		}
 		assertEquals(ObjectId
 				.fromString("00b1f73724f493096d1ffa0b0f1f1482dbb8c936"), treeId);
@@ -741,80 +739,59 @@ public class T0003_BasicTest extends SampleDataRepositoryTestCase {
 
 	private ObjectId insertEmptyBlob() throws IOException {
 		final ObjectId emptyId;
-		ObjectInserter oi = db.newObjectInserter();
-		try {
+		try (ObjectInserter oi = db.newObjectInserter()) {
 			emptyId = oi.insert(Constants.OBJ_BLOB, new byte[] {});
 			oi.flush();
-		} finally {
-			oi.release();
 		}
 		return emptyId;
 	}
 
 	private ObjectId insertTree(Tree tree) throws IOException {
-		ObjectInserter oi = db.newObjectInserter();
-		try {
+		try (ObjectInserter oi = db.newObjectInserter()) {
 			ObjectId id = oi.insert(Constants.OBJ_TREE, tree.format());
 			oi.flush();
 			return id;
-		} finally {
-			oi.release();
 		}
 	}
 
 	private ObjectId insertTree(TreeFormatter tree) throws IOException {
-		ObjectInserter oi = db.newObjectInserter();
-		try {
+		try (ObjectInserter oi = db.newObjectInserter()) {
 			ObjectId id = oi.insert(tree);
 			oi.flush();
 			return id;
-		} finally {
-			oi.release();
 		}
 	}
 
 	private ObjectId insertCommit(final CommitBuilder builder)
 			throws IOException, UnsupportedEncodingException {
-		ObjectInserter oi = db.newObjectInserter();
-		try {
+		try (ObjectInserter oi = db.newObjectInserter()) {
 			ObjectId id = oi.insert(builder);
 			oi.flush();
 			return id;
-		} finally {
-			oi.release();
 		}
 	}
 
 	private RevCommit parseCommit(AnyObjectId id)
 			throws MissingObjectException, IncorrectObjectTypeException,
 			IOException {
-		RevWalk rw = new RevWalk(db);
-		try {
+		try (RevWalk rw = new RevWalk(db)) {
 			return rw.parseCommit(id);
-		} finally {
-			rw.release();
 		}
 	}
 
 	private ObjectId insertTag(final TagBuilder tag) throws IOException,
 			UnsupportedEncodingException {
-		ObjectInserter oi = db.newObjectInserter();
-		try {
+		try (ObjectInserter oi = db.newObjectInserter()) {
 			ObjectId id = oi.insert(tag);
 			oi.flush();
 			return id;
-		} finally {
-			oi.release();
 		}
 	}
 
 	private RevTag parseTag(AnyObjectId id) throws MissingObjectException,
 			IncorrectObjectTypeException, IOException {
-		RevWalk rw = new RevWalk(db);
-		try {
+		try (RevWalk rw = new RevWalk(db)) {
 			return rw.parseTag(id);
-		} finally {
-			rw.release();
 		}
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/DirCacheCheckoutTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/DirCacheCheckoutTest.java
index 48debae932..7a115e1076 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/DirCacheCheckoutTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/DirCacheCheckoutTest.java
@@ -356,15 +356,12 @@ public class DirCacheCheckoutTest extends RepositoryTestCase {
 	}
 
 	ObjectId genSha1(String data) {
-		ObjectInserter w = db.newObjectInserter();
-		try {
+		try (ObjectInserter w = db.newObjectInserter()) {
 			ObjectId id = w.insert(Constants.OBJ_BLOB, data.getBytes());
 			w.flush();
 			return id;
 		} catch (IOException e) {
 			fail(e.toString());
-		} finally {
-			w.release();
 		}
 		return null;
 	}
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/IndexDiffTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/IndexDiffTest.java
index a85198f019..a5cd7b5c0b 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/IndexDiffTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/IndexDiffTest.java
@@ -384,13 +384,10 @@ public class IndexDiffTest extends RepositoryTestCase {
 	}
 
 	private ObjectId insertTree(Tree tree) throws IOException {
-		ObjectInserter oi = db.newObjectInserter();
-		try {
+		try (ObjectInserter oi = db.newObjectInserter()) {
 			ObjectId id = oi.insert(Constants.OBJ_TREE, tree.format());
 			oi.flush();
 			return id;
-		} finally {
-			oi.release();
 		}
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/ReflogConfigTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/ReflogConfigTest.java
index cf8d42f724..7b6d7d4b0d 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/ReflogConfigTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/ReflogConfigTest.java
@@ -109,14 +109,11 @@ public class ReflogConfigTest extends RepositoryTestCase {
 		commit.setAuthor(author);
 		commit.setCommitter(committer);
 		commit.setMessage(commitMsg);
-		ObjectInserter inserter = db.newObjectInserter();
 		ObjectId id;
-		try {
+		try (ObjectInserter inserter = db.newObjectInserter()) {
 			commit.setTreeId(inserter.insert(new TreeFormatter()));
 			id = inserter.insert(commit);
 			inserter.flush();
-		} finally {
-			inserter.release();
 		}
 
 		int nl = commitMsg.indexOf('\n');
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/DefaultNoteMergerTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/DefaultNoteMergerTest.java
index 91608ead13..d3a6f18389 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/DefaultNoteMergerTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/DefaultNoteMergerTest.java
@@ -86,8 +86,8 @@ public class DefaultNoteMergerTest extends RepositoryTestCase {
 	@Override
 	@After
 	public void tearDown() throws Exception {
-		reader.release();
-		inserter.release();
+		reader.close();
+		inserter.close();
 		super.tearDown();
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapMergerTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapMergerTest.java
index 8010fb1aac..be7bead6bd 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapMergerTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapMergerTest.java
@@ -127,8 +127,8 @@ public class NoteMapMergerTest extends RepositoryTestCase {
 	@Override
 	@After
 	public void tearDown() throws Exception {
-		reader.release();
-		inserter.release();
+		reader.close();
+		inserter.close();
 		super.tearDown();
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapTest.java
index c2f63d617f..4539a013f3 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapTest.java
@@ -91,8 +91,8 @@ public class NoteMapTest extends RepositoryTestCase {
 	@Override
 	@After
 	public void tearDown() throws Exception {
-		reader.release();
-		inserter.release();
+		reader.close();
+		inserter.close();
 		super.tearDown();
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/ObjectWalkTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/ObjectWalkTest.java
index dfde7fcf2c..2a59f58c66 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/ObjectWalkTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/ObjectWalkTest.java
@@ -229,15 +229,12 @@ public class ObjectWalkTest extends RevWalkTestCase {
 			Tree A_A = A.addTree("A");
 			Tree A_B = A.addTree("B");
 
-			final ObjectInserter inserter = db.newObjectInserter();
-			try {
+			try (final ObjectInserter inserter = db.newObjectInserter()) {
 				A_A.setId(inserter.insert(Constants.OBJ_TREE, A_A.format()));
 				A_B.setId(inserter.insert(Constants.OBJ_TREE, A_B.format()));
 				A.setId(inserter.insert(Constants.OBJ_TREE, A.format()));
 				root.setId(inserter.insert(Constants.OBJ_TREE, root.format()));
 				inserter.flush();
-			} finally {
-				inserter.release();
 			}
 
 			tree_root = rw.parseTree(root.getId());
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/RevWalkUtilsReachableTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/RevWalkUtilsReachableTest.java
index 855bb80569..10bea0a8b5 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/RevWalkUtilsReachableTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/revwalk/RevWalkUtilsReachableTest.java
@@ -103,12 +103,9 @@ public class RevWalkUtilsReachableTest extends RevWalkTestCase {
 		RevCommit a = commit();
 		Ref branchA = branch("a", a);
 
-		RevWalk walk = new RevWalk(db);
-		try {
+		try (RevWalk walk = new RevWalk(db)) {
 			RevCommit parsedCommit = walk.parseCommit(a.getId());
 			assertContains(parsedCommit, asList(branchA));
-		} finally {
-			walk.release();
 		}
 	}
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/PackParserTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/PackParserTest.java
index 6859dd53a6..c829be900e 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/PackParserTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/PackParserTest.java
@@ -486,8 +486,9 @@ public class PackParserTest extends RepositoryTestCase {
 
 	@After
 	public void release() {
-		if (inserter != null)
-			inserter.release();
+		if (inserter != null) {
+			inserter.close();
+		}
 	}
 
 	private PackParser index(InputStream in) throws IOException {
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ReceivePackAdvertiseRefsHookTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ReceivePackAdvertiseRefsHookTest.java
index 2bd9077677..aa5914fe03 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ReceivePackAdvertiseRefsHookTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/transport/ReceivePackAdvertiseRefsHookTest.java
@@ -543,8 +543,9 @@ public class ReceivePackAdvertiseRefsHookTest extends LocalDiskRepositoryTestCas
 
 	@After
 	public void release() {
-		if (inserter != null)
-			inserter.release();
+		if (inserter != null) {
+			inserter.close();
+		}
 	}
 
 	private void openPack(TemporaryBuffer.Heap buf) throws IOException {
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/FileTreeIteratorJava7Test.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/FileTreeIteratorJava7Test.java
index 741396c519..88754109f7 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/FileTreeIteratorJava7Test.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/FileTreeIteratorJava7Test.java
@@ -89,20 +89,19 @@ public class FileTreeIteratorJava7Test extends RepositoryTestCase {
 		DirCacheEditor dce = dc.editor();
 		final String UNNORMALIZED = "target/";
 		final byte[] UNNORMALIZED_BYTES = Constants.encode(UNNORMALIZED);
-		ObjectInserter oi = db.newObjectInserter();
-		final ObjectId linkid = oi.insert(Constants.OBJ_BLOB,
-				UNNORMALIZED_BYTES, 0,
-				UNNORMALIZED_BYTES.length);
-		oi.release();
-		dce.add(new DirCacheEditor.PathEdit("link") {
-			@Override
-			public void apply(DirCacheEntry ent) {
-				ent.setFileMode(FileMode.SYMLINK);
-				ent.setObjectId(linkid);
-				ent.setLength(UNNORMALIZED_BYTES.length);
-			}
-		});
-		assertTrue(dce.commit());
+		try (ObjectInserter oi = db.newObjectInserter()) {
+			final ObjectId linkid = oi.insert(Constants.OBJ_BLOB,
+					UNNORMALIZED_BYTES, 0, UNNORMALIZED_BYTES.length);
+			dce.add(new DirCacheEditor.PathEdit("link") {
+				@Override
+				public void apply(DirCacheEntry ent) {
+					ent.setFileMode(FileMode.SYMLINK);
+					ent.setObjectId(linkid);
+					ent.setLength(UNNORMALIZED_BYTES.length);
+				}
+			});
+			assertTrue(dce.commit());
+		}
 		new Git(db).commit().setMessage("Adding link").call();
 		new Git(db).reset().setMode(ResetType.HARD).call();
 		DirCacheIterator dci = new DirCacheIterator(db.readDirCache());
@@ -129,19 +128,19 @@ public class FileTreeIteratorJava7Test extends RepositoryTestCase {
 		DirCacheEditor dce = dc.editor();
 		final String NORMALIZED = "target";
 		final byte[] NORMALIZED_BYTES = Constants.encode(NORMALIZED);
-		ObjectInserter oi = db.newObjectInserter();
-		final ObjectId linkid = oi.insert(Constants.OBJ_BLOB, NORMALIZED_BYTES,
-				0, NORMALIZED_BYTES.length);
-		oi.release();
-		dce.add(new DirCacheEditor.PathEdit("link") {
-			@Override
-			public void apply(DirCacheEntry ent) {
-				ent.setFileMode(FileMode.SYMLINK);
-				ent.setObjectId(linkid);
-				ent.setLength(NORMALIZED_BYTES.length);
-			}
-		});
-		assertTrue(dce.commit());
+		try (ObjectInserter oi = db.newObjectInserter()) {
+			final ObjectId linkid = oi.insert(Constants.OBJ_BLOB,
+					NORMALIZED_BYTES, 0, NORMALIZED_BYTES.length);
+			dce.add(new DirCacheEditor.PathEdit("link") {
+				@Override
+				public void apply(DirCacheEntry ent) {
+					ent.setFileMode(FileMode.SYMLINK);
+					ent.setObjectId(linkid);
+					ent.setLength(NORMALIZED_BYTES.length);
+				}
+			});
+			assertTrue(dce.commit());
+		}
 		new Git(db).commit().setMessage("Adding link").call();
 		new Git(db).reset().setMode(ResetType.HARD).call();
 		DirCacheIterator dci = new DirCacheIterator(db.readDirCache());
@@ -166,21 +165,21 @@ public class FileTreeIteratorJava7Test extends RepositoryTestCase {
 	public void testSymlinkActuallyModified() throws Exception {
 		final String NORMALIZED = "target";
 		final byte[] NORMALIZED_BYTES = Constants.encode(NORMALIZED);
-		ObjectInserter oi = db.newObjectInserter();
-		final ObjectId linkid = oi.insert(Constants.OBJ_BLOB, NORMALIZED_BYTES,
-				0, NORMALIZED_BYTES.length);
-		oi.release();
-		DirCache dc = db.lockDirCache();
-		DirCacheEditor dce = dc.editor();
-		dce.add(new DirCacheEditor.PathEdit("link") {
-			@Override
-			public void apply(DirCacheEntry ent) {
-				ent.setFileMode(FileMode.SYMLINK);
-				ent.setObjectId(linkid);
-				ent.setLength(NORMALIZED_BYTES.length);
-			}
-		});
-		assertTrue(dce.commit());
+		try (ObjectInserter oi = db.newObjectInserter()) {
+			final ObjectId linkid = oi.insert(Constants.OBJ_BLOB,
+					NORMALIZED_BYTES, 0, NORMALIZED_BYTES.length);
+			DirCache dc = db.lockDirCache();
+			DirCacheEditor dce = dc.editor();
+			dce.add(new DirCacheEditor.PathEdit("link") {
+				@Override
+				public void apply(DirCacheEntry ent) {
+					ent.setFileMode(FileMode.SYMLINK);
+					ent.setObjectId(linkid);
+					ent.setLength(NORMALIZED_BYTES.length);
+				}
+			});
+			assertTrue(dce.commit());
+		}
 		new Git(db).commit().setMessage("Adding link").call();
 		new Git(db).reset().setMode(ResetType.HARD).call();
 
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/FileTreeIteratorTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/FileTreeIteratorTest.java
index 7964578c36..767e13d114 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/FileTreeIteratorTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/FileTreeIteratorTest.java
@@ -274,9 +274,9 @@ public class FileTreeIteratorTest extends RepositoryTestCase {
 		ObjectId fromRaw = ObjectId.fromRaw(fti.idBuffer(), fti.idOffset());
 		assertEquals("6b584e8ece562ebffc15d38808cd6b98fc3d97ea",
 				fromRaw.getName());
-		ObjectReader objectReader = db.newObjectReader();
-		assertFalse(fti.isModified(dce, false, objectReader));
-		objectReader.release();
+		try (ObjectReader objectReader = db.newObjectReader()) {
+			assertFalse(fti.isModified(dce, false, objectReader));
+		}
 	}
 
 	@Test
@@ -291,15 +291,15 @@ public class FileTreeIteratorTest extends RepositoryTestCase {
 		// Modify previously committed DirCacheEntry and write it back to disk
 		DirCacheEntry dce = db.readDirCache().getEntry("symlink");
 		dce.setFileMode(FileMode.SYMLINK);
-		ObjectReader objectReader = db.newObjectReader();
-		DirCacheCheckout.checkoutEntry(db, dce, objectReader);
-
-		FileTreeIterator fti = new FileTreeIterator(trash, db.getFS(), db
-				.getConfig().get(WorkingTreeOptions.KEY));
-		while (!fti.getEntryPathString().equals("symlink"))
-			fti.next(1);
-		assertFalse(fti.isModified(dce, false, objectReader));
-		objectReader.release();
+		try (ObjectReader objectReader = db.newObjectReader()) {
+			DirCacheCheckout.checkoutEntry(db, dce, objectReader);
+
+			FileTreeIterator fti = new FileTreeIterator(trash, db.getFS(),
+					db.getConfig().get(WorkingTreeOptions.KEY));
+			while (!fti.getEntryPathString().equals("symlink"))
+				fti.next(1);
+			assertFalse(fti.isModified(dce, false, objectReader));
+		}
 	}
 
 	@Test
@@ -327,9 +327,9 @@ public class FileTreeIteratorTest extends RepositoryTestCase {
 		// If the rounding trick does not work we could skip the compareMetaData
 		// test and hope that we are usually testing the intended code path.
 		assertEquals(MetadataDiff.SMUDGED, fti.compareMetadata(dce));
-		ObjectReader objectReader = db.newObjectReader();
-		assertTrue(fti.isModified(dce, false, objectReader));
-		objectReader.release();
+		try (ObjectReader objectReader = db.newObjectReader()) {
+			assertTrue(fti.isModified(dce, false, objectReader));
+		}
 	}
 
 	@Test
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/ForPathTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/ForPathTest.java
index 59c4a8d1bb..eaee8bb4b9 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/ForPathTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/ForPathTest.java
@@ -68,70 +68,69 @@ public class ForPathTest extends RepositoryTestCase {
 	public void testFindObjects() throws Exception {
 		final DirCache tree0 = DirCache.newInCore();
 		final DirCacheBuilder b0 = tree0.builder();
-		ObjectReader or = db.newObjectReader();
-		ObjectInserter oi = db.newObjectInserter();
-
-		DirCacheEntry aDotB = createEntry("a.b", EXECUTABLE_FILE);
-		b0.add(aDotB);
-		DirCacheEntry aSlashB = createEntry("a/b", REGULAR_FILE);
-		b0.add(aSlashB);
-		DirCacheEntry aSlashCSlashD = createEntry("a/c/d", REGULAR_FILE);
-		b0.add(aSlashCSlashD);
-		DirCacheEntry aZeroB = createEntry("a0b", SYMLINK);
-		b0.add(aZeroB);
-		b0.finish();
-		assertEquals(4, tree0.getEntryCount());
-		ObjectId tree = tree0.writeTree(oi);
-
-		// Find the directories that were implicitly created above.
-		TreeWalk tw = new TreeWalk(or);
-		tw.addTree(tree);
-		ObjectId a = null;
-		ObjectId aSlashC = null;
-		while (tw.next()) {
-			if (tw.getPathString().equals("a")) {
-				a = tw.getObjectId(0);
-				tw.enterSubtree();
-				while (tw.next()) {
-					if (tw.getPathString().equals("a/c")) {
-						aSlashC = tw.getObjectId(0);
-						break;
+		try (ObjectReader or = db.newObjectReader();
+				ObjectInserter oi = db.newObjectInserter()) {
+
+			DirCacheEntry aDotB = createEntry("a.b", EXECUTABLE_FILE);
+			b0.add(aDotB);
+			DirCacheEntry aSlashB = createEntry("a/b", REGULAR_FILE);
+			b0.add(aSlashB);
+			DirCacheEntry aSlashCSlashD = createEntry("a/c/d", REGULAR_FILE);
+			b0.add(aSlashCSlashD);
+			DirCacheEntry aZeroB = createEntry("a0b", SYMLINK);
+			b0.add(aZeroB);
+			b0.finish();
+			assertEquals(4, tree0.getEntryCount());
+			ObjectId tree = tree0.writeTree(oi);
+
+			// Find the directories that were implicitly created above.
+			TreeWalk tw = new TreeWalk(or);
+			tw.addTree(tree);
+			ObjectId a = null;
+			ObjectId aSlashC = null;
+			while (tw.next()) {
+				if (tw.getPathString().equals("a")) {
+					a = tw.getObjectId(0);
+					tw.enterSubtree();
+					while (tw.next()) {
+						if (tw.getPathString().equals("a/c")) {
+							aSlashC = tw.getObjectId(0);
+							break;
+						}
 					}
+					break;
 				}
-				break;
 			}
-		}
-
-		assertEquals(a, TreeWalk.forPath(or, "a", tree).getObjectId(0));
-		assertEquals(a, TreeWalk.forPath(or, "a/", tree).getObjectId(0));
-		assertEquals(null, TreeWalk.forPath(or, "/a", tree));
-		assertEquals(null, TreeWalk.forPath(or, "/a/", tree));
-
-		assertEquals(aDotB.getObjectId(), TreeWalk.forPath(or, "a.b", tree)
-				.getObjectId(0));
-		assertEquals(null, TreeWalk.forPath(or, "/a.b", tree));
-		assertEquals(null, TreeWalk.forPath(or, "/a.b/", tree));
-		assertEquals(aDotB.getObjectId(), TreeWalk.forPath(or, "a.b/", tree)
-				.getObjectId(0));
-
-		assertEquals(aZeroB.getObjectId(), TreeWalk.forPath(or, "a0b", tree)
-				.getObjectId(0));
 
-		assertEquals(aSlashB.getObjectId(), TreeWalk.forPath(or, "a/b", tree)
-				.getObjectId(0));
-		assertEquals(aSlashB.getObjectId(), TreeWalk.forPath(or, "b", a)
-				.getObjectId(0));
-
-		assertEquals(aSlashC, TreeWalk.forPath(or, "a/c", tree).getObjectId(0));
-		assertEquals(aSlashC, TreeWalk.forPath(or, "c", a).getObjectId(0));
-
-		assertEquals(aSlashCSlashD.getObjectId(),
-				TreeWalk.forPath(or, "a/c/d", tree).getObjectId(0));
-		assertEquals(aSlashCSlashD.getObjectId(), TreeWalk
-				.forPath(or, "c/d", a).getObjectId(0));
-
-		or.release();
-		oi.release();
+			assertEquals(a, TreeWalk.forPath(or, "a", tree).getObjectId(0));
+			assertEquals(a, TreeWalk.forPath(or, "a/", tree).getObjectId(0));
+			assertEquals(null, TreeWalk.forPath(or, "/a", tree));
+			assertEquals(null, TreeWalk.forPath(or, "/a/", tree));
+
+			assertEquals(aDotB.getObjectId(),
+					TreeWalk.forPath(or, "a.b", tree).getObjectId(0));
+			assertEquals(null, TreeWalk.forPath(or, "/a.b", tree));
+			assertEquals(null, TreeWalk.forPath(or, "/a.b/", tree));
+			assertEquals(aDotB.getObjectId(),
+					TreeWalk.forPath(or, "a.b/", tree).getObjectId(0));
+
+			assertEquals(aZeroB.getObjectId(),
+					TreeWalk.forPath(or, "a0b", tree).getObjectId(0));
+
+			assertEquals(aSlashB.getObjectId(),
+					TreeWalk.forPath(or, "a/b", tree).getObjectId(0));
+			assertEquals(aSlashB.getObjectId(),
+					TreeWalk.forPath(or, "b", a).getObjectId(0));
+
+			assertEquals(aSlashC,
+					TreeWalk.forPath(or, "a/c", tree).getObjectId(0));
+			assertEquals(aSlashC, TreeWalk.forPath(or, "c", a).getObjectId(0));
+
+			assertEquals(aSlashCSlashD.getObjectId(),
+					TreeWalk.forPath(or, "a/c/d", tree).getObjectId(0));
+			assertEquals(aSlashCSlashD.getObjectId(),
+					TreeWalk.forPath(or, "c/d", a).getObjectId(0));
+		}
 	}
 
 }
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/TreeWalkBasicDiffTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/TreeWalkBasicDiffTest.java
index b52a727d8d..aca7c80fd7 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/TreeWalkBasicDiffTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/treewalk/TreeWalkBasicDiffTest.java
@@ -63,52 +63,51 @@ public class TreeWalkBasicDiffTest extends RepositoryTestCase {
 	@Test
 	public void testMissingSubtree_DetectFileAdded_FileModified()
 			throws Exception {
-		final ObjectInserter inserter = db.newObjectInserter();
-		final ObjectId aFileId = inserter.insert(OBJ_BLOB, encode("a"));
-		final ObjectId bFileId = inserter.insert(OBJ_BLOB, encode("b"));
-		final ObjectId cFileId1 = inserter.insert(OBJ_BLOB, encode("c-1"));
-		final ObjectId cFileId2 = inserter.insert(OBJ_BLOB, encode("c-2"));
+		final ObjectId oldTree, newTree, bFileId, cFileId1, cFileId2;
+		try (ObjectInserter inserter = db.newObjectInserter()) {
+			final ObjectId aFileId = inserter.insert(OBJ_BLOB, encode("a"));
+			bFileId = inserter.insert(OBJ_BLOB, encode("b"));
+			cFileId1 = inserter.insert(OBJ_BLOB, encode("c-1"));
+			cFileId2 = inserter.insert(OBJ_BLOB, encode("c-2"));
 
-		// Create sub-a/empty, sub-c/empty = hello.
-		final ObjectId oldTree;
-		{
-			final Tree root = new Tree(db);
+			// Create sub-a/empty, sub-c/empty = hello.
 			{
-				final Tree subA = root.addTree("sub-a");
-				subA.addFile("empty").setId(aFileId);
-				subA.setId(inserter.insert(OBJ_TREE, subA.format()));
+				final Tree root = new Tree(db);
+				{
+					final Tree subA = root.addTree("sub-a");
+					subA.addFile("empty").setId(aFileId);
+					subA.setId(inserter.insert(OBJ_TREE, subA.format()));
+				}
+				{
+					final Tree subC = root.addTree("sub-c");
+					subC.addFile("empty").setId(cFileId1);
+					subC.setId(inserter.insert(OBJ_TREE, subC.format()));
+				}
+				oldTree = inserter.insert(OBJ_TREE, root.format());
 			}
-			{
-				final Tree subC = root.addTree("sub-c");
-				subC.addFile("empty").setId(cFileId1);
-				subC.setId(inserter.insert(OBJ_TREE, subC.format()));
-			}
-			oldTree = inserter.insert(OBJ_TREE, root.format());
-		}
 
-		// Create sub-a/empty, sub-b/empty, sub-c/empty.
-		final ObjectId newTree;
-		{
-			final Tree root = new Tree(db);
-			{
-				final Tree subA = root.addTree("sub-a");
-				subA.addFile("empty").setId(aFileId);
-				subA.setId(inserter.insert(OBJ_TREE, subA.format()));
-			}
-			{
-				final Tree subB = root.addTree("sub-b");
-				subB.addFile("empty").setId(bFileId);
-				subB.setId(inserter.insert(OBJ_TREE, subB.format()));
-			}
+			// Create sub-a/empty, sub-b/empty, sub-c/empty.
 			{
-				final Tree subC = root.addTree("sub-c");
-				subC.addFile("empty").setId(cFileId2);
-				subC.setId(inserter.insert(OBJ_TREE, subC.format()));
+				final Tree root = new Tree(db);
+				{
+					final Tree subA = root.addTree("sub-a");
+					subA.addFile("empty").setId(aFileId);
+					subA.setId(inserter.insert(OBJ_TREE, subA.format()));
+				}
+				{
+					final Tree subB = root.addTree("sub-b");
+					subB.addFile("empty").setId(bFileId);
+					subB.setId(inserter.insert(OBJ_TREE, subB.format()));
+				}
+				{
+					final Tree subC = root.addTree("sub-c");
+					subC.addFile("empty").setId(cFileId2);
+					subC.setId(inserter.insert(OBJ_TREE, subC.format()));
+				}
+				newTree = inserter.insert(OBJ_TREE, root.format());
 			}
-			newTree = inserter.insert(OBJ_TREE, root.format());
+			inserter.flush();
 		}
-		inserter.flush();
-		inserter.release();
 
 		final TreeWalk tw = new TreeWalk(db);
 		tw.reset(oldTree, newTree);