text: public RebaseCommand setUpstream(AnyObjectId upstream) {try {this.upstreamCommit = walk.parseCommit(upstream);this.upstreamCommitName = upstream.name();} catch (IOException e) {throw new JGitInternalException(MessageFormat.format(JGitText.get().couldNotReadObjectWhileParsingCommit,upstream.name()), e);}return this;}