Merge branch 'stable-4.1'

* stable-4.1:
  pgm: Open RevWalk and TreeWalk in try-with-resource
  ant: Open Repository and Git in try-with-resource
  pgm: Create instances of Git in try-with-resource
  FanoutBucket: Create ObjectInserter.Formatter in try-with-resource
  Fix compiler warnings in DiffFormatter.writeGitLinkText

Change-Id: I448ecc9a1334977d9f304dd61ea20c7a8e692b10
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

20 files changed, 320 insertions, 292 deletions

diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Add.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Add.java
index 12aac77e9d..c36c485197 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Add.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Add.java
@@ -62,10 +62,12 @@ class Add extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		AddCommand addCmd = new Git(db).add();
-		addCmd.setUpdate(update);
-		for (String p : filepatterns)
-			addCmd.addFilepattern(p);
-		addCmd.call();
+		try (Git git = new Git(db)) {
+			AddCommand addCmd = git.add();
+			addCmd.setUpdate(update);
+			for (String p : filepatterns)
+				addCmd.addFilepattern(p);
+			addCmd.call();
+		}
 	}
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Archive.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Archive.java
index 80bb9ec9df..fe2ba83bc6 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Archive.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Archive.java
@@ -87,8 +87,8 @@ class Archive extends TextBuiltin {
 			else
 				stream = outs;
 
-			try {
-				ArchiveCommand cmd = new Git(db).archive()
+			try (Git git = new Git(db)) {
+				ArchiveCommand cmd = git.archive()
 					.setTree(tree)
 					.setFormat(format)
 					.setPrefix(prefix)
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Branch.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Branch.java
index 72e37158cd..83a1ca7e25 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Branch.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Branch.java
@@ -186,29 +186,31 @@ class Branch extends TextBuiltin {
 		// This can happen if HEAD is stillborn
 		if (head != null) {
 			String current = head.getLeaf().getName();
-			ListBranchCommand command = new Git(db).branchList();
-			if (all)
-				command.setListMode(ListMode.ALL);
-			else if (remote)
-				command.setListMode(ListMode.REMOTE);
+			try (Git git = new Git(db)) {
+				ListBranchCommand command = git.branchList();
+				if (all)
+					command.setListMode(ListMode.ALL);
+				else if (remote)
+					command.setListMode(ListMode.REMOTE);
 
-			if (containsCommitish != null)
-				command.setContains(containsCommitish);
+				if (containsCommitish != null)
+					command.setContains(containsCommitish);
 
-			List<Ref> refs = command.call();
-			for (Ref ref : refs) {
-				if (ref.getName().equals(Constants.HEAD))
-					addRef("(no branch)", head); //$NON-NLS-1$
-			}
+				List<Ref> refs = command.call();
+				for (Ref ref : refs) {
+					if (ref.getName().equals(Constants.HEAD))
+						addRef("(no branch)", head); //$NON-NLS-1$
+				}
 
-			addRefs(refs, Constants.R_HEADS);
-			addRefs(refs, Constants.R_REMOTES);
+				addRefs(refs, Constants.R_HEADS);
+				addRefs(refs, Constants.R_REMOTES);
 
-			try (ObjectReader reader = db.newObjectReader()) {
-				for (final Entry<String, Ref> e : printRefs.entrySet()) {
-					final Ref ref = e.getValue();
-					printHead(reader, e.getKey(),
-							current.equals(ref.getName()), ref);
+				try (ObjectReader reader = db.newObjectReader()) {
+					for (final Entry<String, Ref> e : printRefs.entrySet()) {
+						final Ref ref = e.getValue();
+						printHead(reader, e.getKey(),
+								current.equals(ref.getName()), ref);
+					}
 				}
 			}
 		}
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Checkout.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Checkout.java
index 56d4fcff02..45794629ec 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Checkout.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Checkout.java
@@ -89,47 +89,49 @@ class Checkout extends TextBuiltin {
 				throw die(CLIText.get().onBranchToBeBorn);
 		}
 
-		CheckoutCommand command = new Git(db).checkout();
-		if (paths.size() > 0) {
-			command.setStartPoint(name);
-			for (String path : paths)
-				command.addPath(path);
-		} else {
-			command.setCreateBranch(createBranch);
-			command.setName(name);
-			command.setForce(force);
-			command.setOrphan(orphan);
-		}
-		try {
-			String oldBranch = db.getBranch();
-			Ref ref = command.call();
-			if (ref == null)
-				return;
-			if (Repository.shortenRefName(ref.getName()).equals(oldBranch)) {
+		try (Git git = new Git(db)) {
+			CheckoutCommand command = git.checkout();
+			if (paths.size() > 0) {
+				command.setStartPoint(name);
+				for (String path : paths)
+					command.addPath(path);
+			} else {
+				command.setCreateBranch(createBranch);
+				command.setName(name);
+				command.setForce(force);
+				command.setOrphan(orphan);
+			}
+			try {
+				String oldBranch = db.getBranch();
+				Ref ref = command.call();
+				if (ref == null)
+					return;
+				if (Repository.shortenRefName(ref.getName()).equals(oldBranch)) {
+					outw.println(MessageFormat.format(
+							CLIText.get().alreadyOnBranch,
+							name));
+					return;
+				}
+				if (createBranch || orphan)
+					outw.println(MessageFormat.format(
+							CLIText.get().switchedToNewBranch, name));
+				else
+					outw.println(MessageFormat.format(
+							CLIText.get().switchedToBranch,
+							Repository.shortenRefName(ref.getName())));
+			} catch (RefNotFoundException e) {
 				outw.println(MessageFormat.format(
-						CLIText.get().alreadyOnBranch,
+						CLIText.get().pathspecDidNotMatch,
+						name));
+			} catch (RefAlreadyExistsException e) {
+				throw die(MessageFormat.format(CLIText.get().branchAlreadyExists,
 						name));
-				return;
+			} catch (CheckoutConflictException e) {
+				outw.println(CLIText.get().checkoutConflict);
+				for (String path : e.getConflictingPaths())
+					outw.println(MessageFormat.format(
+							CLIText.get().checkoutConflictPathLine, path));
 			}
-			if (createBranch || orphan)
-				outw.println(MessageFormat.format(
-						CLIText.get().switchedToNewBranch, name));
-			else
-				outw.println(MessageFormat.format(
-						CLIText.get().switchedToBranch,
-						Repository.shortenRefName(ref.getName())));
-		} catch (RefNotFoundException e) {
-			outw.println(MessageFormat.format(
-					CLIText.get().pathspecDidNotMatch,
-					name));
-		} catch (RefAlreadyExistsException e) {
-			throw die(MessageFormat.format(CLIText.get().branchAlreadyExists,
-					name));
-		} catch (CheckoutConflictException e) {
-			outw.println(CLIText.get().checkoutConflict);
-			for (String path : e.getConflictingPaths())
-				outw.println(MessageFormat.format(
-						CLIText.get().checkoutConflictPathLine, path));
 		}
 	}
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Commit.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Commit.java
index 14c449a6b3..f18242d684 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Commit.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Commit.java
@@ -80,37 +80,39 @@ class Commit extends TextBuiltin {
 	@Override
 	protected void run() throws NoHeadException, NoMessageException,
 			ConcurrentRefUpdateException, JGitInternalException, Exception {
-		CommitCommand commitCmd = new Git(db).commit();
-		if (author != null)
-			commitCmd.setAuthor(RawParseUtils.parsePersonIdent(author));
-		if (message != null)
-			commitCmd.setMessage(message);
-		if (only && paths.isEmpty())
-			throw die(CLIText.get().pathsRequired);
-		if (only && all)
-			throw die(CLIText.get().onlyOneOfIncludeOnlyAllInteractiveCanBeUsed);
-		if (!paths.isEmpty())
-			for (String p : paths)
-				commitCmd.setOnly(p);
-		commitCmd.setAmend(amend);
-		commitCmd.setAll(all);
-		Ref head = db.getRef(Constants.HEAD);
-		RevCommit commit;
-		try {
-			commit = commitCmd.call();
-		} catch (JGitInternalException e) {
-			throw die(e.getMessage());
-		}
+		try (Git git = new Git(db)) {
+			CommitCommand commitCmd = git.commit();
+			if (author != null)
+				commitCmd.setAuthor(RawParseUtils.parsePersonIdent(author));
+			if (message != null)
+				commitCmd.setMessage(message);
+			if (only && paths.isEmpty())
+				throw die(CLIText.get().pathsRequired);
+			if (only && all)
+				throw die(CLIText.get().onlyOneOfIncludeOnlyAllInteractiveCanBeUsed);
+			if (!paths.isEmpty())
+				for (String p : paths)
+					commitCmd.setOnly(p);
+			commitCmd.setAmend(amend);
+			commitCmd.setAll(all);
+			Ref head = db.getRef(Constants.HEAD);
+			RevCommit commit;
+			try {
+				commit = commitCmd.call();
+			} catch (JGitInternalException e) {
+				throw die(e.getMessage());
+			}
 
-		String branchName;
-		if (!head.isSymbolic())
-			branchName = CLIText.get().branchDetachedHEAD;
-		else {
-			branchName = head.getTarget().getName();
-			if (branchName.startsWith(Constants.R_HEADS))
-				branchName = branchName.substring(Constants.R_HEADS.length());
+			String branchName;
+			if (!head.isSymbolic())
+				branchName = CLIText.get().branchDetachedHEAD;
+			else {
+				branchName = head.getTarget().getName();
+				if (branchName.startsWith(Constants.R_HEADS))
+					branchName = branchName.substring(Constants.R_HEADS.length());
+			}
+			outw.println("[" + branchName + " " + commit.name() + "] " //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
+					+ commit.getShortMessage());
 		}
-		outw.println("[" + branchName + " " + commit.name() + "] " //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
-				+ commit.getShortMessage());
 	}
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Describe.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Describe.java
index 901e5604ae..ec000f388b 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Describe.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Describe.java
@@ -61,20 +61,21 @@ class Describe extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		DescribeCommand cmd = new Git(db).describe();
-		if (tree != null)
-			cmd.setTarget(tree);
-		cmd.setLong(longDesc);
-		String result = null;
-		try {
-			result = cmd.call();
-		} catch (RefNotFoundException e) {
-			throw die(CLIText.get().noNamesFound, e);
-		}
-		if (result == null)
-			throw die(CLIText.get().noNamesFound);
+		try (Git git = new Git(db)) {
+			DescribeCommand cmd = git.describe();
+			if (tree != null)
+				cmd.setTarget(tree);
+			cmd.setLong(longDesc);
+			String result = null;
+			try {
+				result = cmd.call();
+			} catch (RefNotFoundException e) {
+				throw die(CLIText.get().noNamesFound, e);
+			}
+			if (result == null)
+				throw die(CLIText.get().noNamesFound);
 
-		outw.println(result);
+			outw.println(result);
+		}
 	}
-
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/DiffTree.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/DiffTree.java
index d89053c4cb..32adf6df0c 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/DiffTree.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/DiffTree.java
@@ -74,46 +74,47 @@ class DiffTree extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		final TreeWalk walk = new TreeWalk(db);
-		walk.setRecursive(recursive);
-		for (final AbstractTreeIterator i : trees)
-			walk.addTree(i);
-		walk.setFilter(AndTreeFilter.create(TreeFilter.ANY_DIFF, pathFilter));
+		try (final TreeWalk walk = new TreeWalk(db)) {
+			walk.setRecursive(recursive);
+			for (final AbstractTreeIterator i : trees)
+				walk.addTree(i);
+			walk.setFilter(AndTreeFilter.create(TreeFilter.ANY_DIFF, pathFilter));
 
-		final int nTree = walk.getTreeCount();
-		while (walk.next()) {
-			for (int i = 1; i < nTree; i++)
-				outw.print(':');
-			for (int i = 0; i < nTree; i++) {
-				final FileMode m = walk.getFileMode(i);
-				final String s = m.toString();
-				for (int pad = 6 - s.length(); pad > 0; pad--)
-					outw.print('0');
-				outw.print(s);
-				outw.print(' ');
-			}
+			final int nTree = walk.getTreeCount();
+			while (walk.next()) {
+				for (int i = 1; i < nTree; i++)
+					outw.print(':');
+				for (int i = 0; i < nTree; i++) {
+					final FileMode m = walk.getFileMode(i);
+					final String s = m.toString();
+					for (int pad = 6 - s.length(); pad > 0; pad--)
+						outw.print('0');
+					outw.print(s);
+					outw.print(' ');
+				}
 
-			for (int i = 0; i < nTree; i++) {
-				outw.print(walk.getObjectId(i).name());
-				outw.print(' ');
-			}
+				for (int i = 0; i < nTree; i++) {
+					outw.print(walk.getObjectId(i).name());
+					outw.print(' ');
+				}
 
-			char chg = 'M';
-			if (nTree == 2) {
-				final int m0 = walk.getRawMode(0);
-				final int m1 = walk.getRawMode(1);
-				if (m0 == 0 && m1 != 0)
-					chg = 'A';
-				else if (m0 != 0 && m1 == 0)
-					chg = 'D';
-				else if (m0 != m1 && walk.idEqual(0, 1))
-					chg = 'T';
-			}
-			outw.print(chg);
+				char chg = 'M';
+				if (nTree == 2) {
+					final int m0 = walk.getRawMode(0);
+					final int m1 = walk.getRawMode(1);
+					if (m0 == 0 && m1 != 0)
+						chg = 'A';
+					else if (m0 != 0 && m1 == 0)
+						chg = 'D';
+					else if (m0 != m1 && walk.idEqual(0, 1))
+						chg = 'T';
+				}
+				outw.print(chg);
 
-			outw.print('\t');
-			outw.print(walk.getPathString());
-			outw.println();
+				outw.print('\t');
+				outw.print(walk.getPathString());
+				outw.println();
+			}
 		}
 	}
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Fetch.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Fetch.java
index 186fdd8a22..ed06733a44 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Fetch.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Fetch.java
@@ -104,31 +104,32 @@ class Fetch extends AbstractFetchCommand {
 
 	@Override
 	protected void run() throws Exception {
-		Git git = new Git(db);
-		FetchCommand fetch = git.fetch();
-		if (fsck != null)
-			fetch.setCheckFetchedObjects(fsck.booleanValue());
-		if (prune != null)
-			fetch.setRemoveDeletedRefs(prune.booleanValue());
-		if (toget != null)
-			fetch.setRefSpecs(toget);
-		if (tags != null) {
-			fetch.setTagOpt(tags.booleanValue() ? TagOpt.FETCH_TAGS
-					: TagOpt.NO_TAGS);
+		try (Git git = new Git(db)) {
+			FetchCommand fetch = git.fetch();
+			if (fsck != null)
+				fetch.setCheckFetchedObjects(fsck.booleanValue());
+			if (prune != null)
+				fetch.setRemoveDeletedRefs(prune.booleanValue());
+			if (toget != null)
+				fetch.setRefSpecs(toget);
+			if (tags != null) {
+				fetch.setTagOpt(tags.booleanValue() ? TagOpt.FETCH_TAGS
+						: TagOpt.NO_TAGS);
+			}
+			if (0 <= timeout)
+				fetch.setTimeout(timeout);
+			fetch.setDryRun(dryRun);
+			fetch.setRemote(remote);
+			if (thin != null)
+				fetch.setThin(thin.booleanValue());
+			if (quiet == null || !quiet.booleanValue())
+				fetch.setProgressMonitor(new TextProgressMonitor(errw));
+
+			FetchResult result = fetch.call();
+			if (result.getTrackingRefUpdates().isEmpty())
+				return;
+
+			showFetchResult(result);
 		}
-		if (0 <= timeout)
-			fetch.setTimeout(timeout);
-		fetch.setDryRun(dryRun);
-		fetch.setRemote(remote);
-		if (thin != null)
-			fetch.setThin(thin.booleanValue());
-		if (quiet == null || !quiet.booleanValue())
-			fetch.setProgressMonitor(new TextProgressMonitor(errw));
-
-		FetchResult result = fetch.call();
-		if (result.getTrackingRefUpdates().isEmpty())
-			return;
-
-		showFetchResult(result);
 	}
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/LsTree.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/LsTree.java
index 4b16ed8800..872ea67774 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/LsTree.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/LsTree.java
@@ -72,27 +72,28 @@ class LsTree extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		final TreeWalk walk = new TreeWalk(db);
-		walk.reset(); // drop the first empty tree, which we do not need here
-		if (paths.size() > 0)
-			walk.setFilter(PathFilterGroup.createFromStrings(paths));
-		walk.setRecursive(recursive);
-		walk.addTree(tree);
+		try (final TreeWalk walk = new TreeWalk(db)) {
+			walk.reset(); // drop the first empty tree, which we do not need here
+			if (paths.size() > 0)
+				walk.setFilter(PathFilterGroup.createFromStrings(paths));
+			walk.setRecursive(recursive);
+			walk.addTree(tree);
 
-		while (walk.next()) {
-			final FileMode mode = walk.getFileMode(0);
-			if (mode == FileMode.TREE)
-				outw.print('0');
-			outw.print(mode);
-			outw.print(' ');
-			outw.print(Constants.typeString(mode.getObjectType()));
+			while (walk.next()) {
+				final FileMode mode = walk.getFileMode(0);
+				if (mode == FileMode.TREE)
+					outw.print('0');
+				outw.print(mode);
+				outw.print(' ');
+				outw.print(Constants.typeString(mode.getObjectType()));
 
-			outw.print(' ');
-			outw.print(walk.getObjectId(0).name());
+				outw.print(' ');
+				outw.print(walk.getObjectId(0).name());
 
-			outw.print('\t');
-			outw.print(QuotedString.GIT_PATH.quote(walk.getPathString()));
-			outw.println();
+				outw.print('\t');
+				outw.print(QuotedString.GIT_PATH.quote(walk.getPathString()));
+				outw.println();
+			}
 		}
 	}
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Merge.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Merge.java
index 93c4388dbc..e0ff0583cb 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Merge.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Merge.java
@@ -121,22 +121,23 @@ class Merge extends TextBuiltin {
 					CLIText.get().refDoesNotExistOrNoCommit, ref));
 
 		Ref oldHead = db.getRef(Constants.HEAD);
-		Git git = new Git(db);
-		MergeCommand mergeCmd = git.merge().setStrategy(mergeStrategy)
-				.setSquash(squash).setFastForward(ff).setCommit(!noCommit);
-		if (srcRef != null)
-			mergeCmd.include(srcRef);
-		else
-			mergeCmd.include(src);
+		MergeResult result;
+		try (Git git = new Git(db)) {
+			MergeCommand mergeCmd = git.merge().setStrategy(mergeStrategy)
+					.setSquash(squash).setFastForward(ff).setCommit(!noCommit);
+			if (srcRef != null)
+				mergeCmd.include(srcRef);
+			else
+				mergeCmd.include(src);
 
-		if (message != null)
-			mergeCmd.setMessage(message);
+			if (message != null)
+				mergeCmd.setMessage(message);
 
-		MergeResult result;
-		try {
-			result = mergeCmd.call();
-		} catch (CheckoutConflictException e) {
-			result = new MergeResult(e.getConflictingPaths()); // CHECKOUT_CONFLICT
+			try {
+				result = mergeCmd.call();
+			} catch (CheckoutConflictException e) {
+				result = new MergeResult(e.getConflictingPaths()); // CHECKOUT_CONFLICT
+			}
 		}
 
 		switch (result.getMergeStatus()) {
@@ -206,12 +207,13 @@ class Merge extends TextBuiltin {
 
 	private boolean isMergedInto(Ref oldHead, AnyObjectId src)
 			throws IOException {
-		RevWalk revWalk = new RevWalk(db);
-		ObjectId oldHeadObjectId = oldHead.getPeeledObjectId();
-		if (oldHeadObjectId == null)
-			oldHeadObjectId = oldHead.getObjectId();
-		RevCommit oldHeadCommit = revWalk.lookupCommit(oldHeadObjectId);
-		RevCommit srcCommit = revWalk.lookupCommit(src);
-		return revWalk.isMergedInto(oldHeadCommit, srcCommit);
+		try (RevWalk revWalk = new RevWalk(db)) {
+			ObjectId oldHeadObjectId = oldHead.getPeeledObjectId();
+			if (oldHeadObjectId == null)
+				oldHeadObjectId = oldHead.getObjectId();
+			RevCommit oldHeadCommit = revWalk.lookupCommit(oldHeadObjectId);
+			RevCommit srcCommit = revWalk.lookupCommit(src);
+			return revWalk.isMergedInto(oldHeadCommit, srcCommit);
+		}
 	}
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Push.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Push.java
index 4268f214fd..1879ef51ff 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Push.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Push.java
@@ -109,24 +109,25 @@ class Push extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		Git git = new Git(db);
-		PushCommand push = git.push();
-		push.setDryRun(dryRun);
-		push.setForce(force);
-		push.setProgressMonitor(new TextProgressMonitor(errw));
-		push.setReceivePack(receivePack);
-		push.setRefSpecs(refSpecs);
-		if (all)
-			push.setPushAll();
-		if (tags)
-			push.setPushTags();
-		push.setRemote(remote);
-		push.setThin(thin);
-		push.setTimeout(timeout);
-		Iterable<PushResult> results = push.call();
-		for (PushResult result : results) {
-			try (ObjectReader reader = db.newObjectReader()) {
-				printPushResult(reader, result.getURI(), result);
+		try (Git git = new Git(db)) {
+			PushCommand push = git.push();
+			push.setDryRun(dryRun);
+			push.setForce(force);
+			push.setProgressMonitor(new TextProgressMonitor(errw));
+			push.setReceivePack(receivePack);
+			push.setRefSpecs(refSpecs);
+			if (all)
+				push.setPushAll();
+			if (tags)
+				push.setPushTags();
+			push.setRemote(remote);
+			push.setThin(thin);
+			push.setTimeout(timeout);
+			Iterable<PushResult> results = push.call();
+			for (PushResult result : results) {
+				try (ObjectReader reader = db.newObjectReader()) {
+					printPushResult(reader, result.getURI(), result);
+				}
 			}
 		}
 	}
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Reflog.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Reflog.java
index aa90f8d50c..86a021dee1 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Reflog.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Reflog.java
@@ -59,13 +59,15 @@ class Reflog extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		ReflogCommand cmd = new Git(db).reflog();
-		if (ref != null)
-			cmd.setRef(ref);
-		Collection<ReflogEntry> entries = cmd.call();
-		int i = 0;
-		for (ReflogEntry entry : entries) {
-			outw.println(toString(entry, i++));
+		try (Git git = new Git(db)) {
+			ReflogCommand cmd = git.reflog();
+			if (ref != null)
+				cmd.setRef(ref);
+			Collection<ReflogEntry> entries = cmd.call();
+			int i = 0;
+			for (ReflogEntry entry : entries) {
+				outw.println(toString(entry, i++));
+			}
 		}
 	}
 
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Reset.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Reset.java
index f4cbcafed1..6d1b1c5481 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Reset.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Reset.java
@@ -66,19 +66,21 @@ class Reset extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		ResetCommand command = new Git(db).reset();
-		command.setRef(commit);
-		ResetType mode = null;
-		if (soft)
-			mode = selectMode(mode, ResetType.SOFT);
-		if (mixed)
-			mode = selectMode(mode, ResetType.MIXED);
-		if (hard)
-			mode = selectMode(mode, ResetType.HARD);
-		if (mode == null)
-			throw die("no reset mode set");
-		command.setMode(mode);
-		command.call();
+		try (Git git = new Git(db)) {
+			ResetCommand command = git.reset();
+			command.setRef(commit);
+			ResetType mode = null;
+			if (soft)
+				mode = selectMode(mode, ResetType.SOFT);
+			if (mixed)
+				mode = selectMode(mode, ResetType.MIXED);
+			if (hard)
+				mode = selectMode(mode, ResetType.HARD);
+			if (mode == null)
+				throw die("no reset mode set");
+			command.setMode(mode);
+			command.call();
+		}
 	}
 
 	private static ResetType selectMode(ResetType mode, ResetType want) {
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Rm.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Rm.java
index 816b3104c2..f4f864b397 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Rm.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Rm.java
@@ -63,10 +63,11 @@ class Rm extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		RmCommand command = new Git(db).rm();
-		for (String p : paths)
-			command.addFilepattern(p);
-		command.call();
+		try (Git git = new Git(db)) {
+			RmCommand command = git.rm();
+			for (String p : paths)
+				command.addFilepattern(p);
+			command.call();
+		}
 	}
-
 }
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Show.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Show.java
index b668139b5e..c5986b01aa 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Show.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Show.java
@@ -251,16 +251,17 @@ class Show extends TextBuiltin {
 
 	private void show(RevTree obj) throws MissingObjectException,
 			IncorrectObjectTypeException, CorruptObjectException, IOException {
-		final TreeWalk walk = new TreeWalk(db);
-		walk.reset();
-		walk.addTree(obj);
-
-		while (walk.next()) {
-			outw.print(walk.getPathString());
-			final FileMode mode = walk.getFileMode(0);
-			if (mode == FileMode.TREE)
-				outw.print("/"); //$NON-NLS-1$
-			outw.println();
+		try (final TreeWalk walk = new TreeWalk(db)) {
+			walk.reset();
+			walk.addTree(obj);
+
+			while (walk.next()) {
+				outw.print(walk.getPathString());
+				final FileMode mode = walk.getFileMode(0);
+				if (mode == FileMode.TREE)
+					outw.print("/"); //$NON-NLS-1$
+				outw.println();
+			}
 		}
 	}
 
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Status.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Status.java
index 12d4208152..be82d070f7 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Status.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Status.java
@@ -88,12 +88,14 @@ class Status extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		StatusCommand statusCommand = new Git(db).status();
-		if (filterPaths != null && filterPaths.size() > 0)
-			for (String path : filterPaths)
-				statusCommand.addPath(path);
-		org.eclipse.jgit.api.Status status = statusCommand.call();
-		printStatus(status);
+		try (Git git = new Git(db)) {
+			StatusCommand statusCommand = git.status();
+			if (filterPaths != null && filterPaths.size() > 0)
+				for (String path : filterPaths)
+					statusCommand.addPath(path);
+			org.eclipse.jgit.api.Status status = statusCommand.call();
+			printStatus(status);
+		}
 	}
 
 	private void printStatus(org.eclipse.jgit.api.Status status)
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Tag.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Tag.java
index a90d4c4dad..45fceb570f 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Tag.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Tag.java
@@ -79,26 +79,28 @@ class Tag extends TextBuiltin {
 
 	@Override
 	protected void run() throws Exception {
-		Git git = new Git(db);
-		if (tagName != null) {
-			TagCommand command = git.tag().setForceUpdate(force)
-					.setMessage(message).setName(tagName);
+		try (Git git = new Git(db)) {
+			if (tagName != null) {
+				TagCommand command = git.tag().setForceUpdate(force)
+						.setMessage(message).setName(tagName);
 
-			if (object != null) {
-				RevWalk walk = new RevWalk(db);
-				command.setObjectId(walk.parseAny(object));
-			}
-			try {
-				command.call();
-			} catch (RefAlreadyExistsException e) {
-				throw die(MessageFormat.format(CLIText.get().tagAlreadyExists,
-						tagName));
-			}
-		} else {
-			ListTagCommand command = git.tagList();
-			List<Ref> list = command.call();
-			for (Ref ref : list) {
-				outw.println(Repository.shortenRefName(ref.getName()));
+				if (object != null) {
+					try (RevWalk walk = new RevWalk(db)) {
+						command.setObjectId(walk.parseAny(object));
+					}
+				}
+				try {
+					command.call();
+				} catch (RefAlreadyExistsException e) {
+					throw die(MessageFormat.format(CLIText.get().tagAlreadyExists,
+							tagName));
+				}
+			} else {
+				ListTagCommand command = git.tagList();
+				List<Ref> list = command.call();
+				for (Ref ref : list) {
+					outw.println(Repository.shortenRefName(ref.getName()));
+				}
 			}
 		}
 	}
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/DiffAlgorithms.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/DiffAlgorithms.java
index 24d717dfd8..df7ebb78b8 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/DiffAlgorithms.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/DiffAlgorithms.java
@@ -173,9 +173,9 @@ class DiffAlgorithms extends TextBuiltin {
 		int maxN = 0;
 
 		AbbreviatedObjectId startId;
-		try (ObjectReader or = db.newObjectReader()) {
+		try (ObjectReader or = db.newObjectReader();
+			RevWalk rw = new RevWalk(or)) {
 			final MutableObjectId id = new MutableObjectId();
-			RevWalk rw = new RevWalk(or);
 			TreeWalk tw = new TreeWalk(or);
 			tw.setFilter(TreeFilter.ANY_DIFF);
 			tw.setRecursive(true);
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/ShowPackDelta.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/ShowPackDelta.java
index 7b5cdbf8f7..d3eb245cd9 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/ShowPackDelta.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/ShowPackDelta.java
@@ -75,7 +75,10 @@ class ShowPackDelta extends TextBuiltin {
 	@Override
 	protected void run() throws Exception {
 		ObjectReader reader = db.newObjectReader();
-		RevObject obj = new RevWalk(reader).parseAny(objectId);
+		RevObject obj;
+		try (RevWalk rw = new RevWalk(reader)) {
+			obj = rw.parseAny(objectId);
+		}
 		byte[] delta = getDelta(reader, obj);
 
 		// We're crossing our fingers that this will be a delta. Double
diff --git a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/TextHashFunctions.java b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/TextHashFunctions.java
index dcfa8cf00a..dcbc37bed6 100644
--- a/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/TextHashFunctions.java
+++ b/org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/debug/TextHashFunctions.java
@@ -300,10 +300,10 @@ class TextHashFunctions extends TextBuiltin {
 
 		long fileCnt = 0;
 		long lineCnt = 0;
-		try (ObjectReader or = db.newObjectReader()) {
-			final MutableObjectId id = new MutableObjectId();
+		try (ObjectReader or = db.newObjectReader();
 			RevWalk rw = new RevWalk(or);
-			TreeWalk tw = new TreeWalk(or);
+			TreeWalk tw = new TreeWalk(or)) {
+			final MutableObjectId id = new MutableObjectId();
 			tw.reset(rw.parseTree(db.resolve(Constants.HEAD)));
 			tw.setRecursive(true);