pgm: Handle exceptions in Show command

This avoids we show a stacktrace on the console by default when this
type of exception is thrown during the run method is executed.

Change-Id: I1c6cc5ecdc44b81e5f3f9b7dc64c3653de5475ba
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Show.java

@@ -59,6 +59,7 @@ import org.eclipse.jgit.diff.RenameDetector;
 import org.eclipse.jgit.errors.CorruptObjectException;
 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
 import org.eclipse.jgit.errors.MissingObjectException;
+import org.eclipse.jgit.errors.RevisionSyntaxException;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.FileMode;
 import org.eclipse.jgit.lib.ObjectId;
@@ -175,7 +176,7 @@ class Show extends TextBuiltin {
 	/** {@inheritDoc} */
 	@SuppressWarnings("boxing")
 	@Override
-	protected void run() throws Exception {
+	protected void run() {
 		diffFmt.setRepository(db);
 		try {
 			diffFmt.setPathFilter(pathFilter);
@@ -224,6 +225,8 @@ class Show extends TextBuiltin {
 							obj.getType()));
 				}
 			}
+		} catch (RevisionSyntaxException | IOException e) {
+			throw die(e.getMessage(), e);
 		} finally {
 			diffFmt.close();
 		}
@@ -273,7 +276,7 @@ class Show extends TextBuiltin {
 		}
 	}
 
-	private void show(RevWalk rw, RevCommit c) throws Exception {
+	private void show(RevWalk rw, RevCommit c) throws IOException {
 		char[] outbuffer = new char[Constants.OBJECT_ID_LENGTH * 2];
 
 		outw.print(CLIText.get().commitLabel);