### Question:
GrepCommand implements CliCommand { @Override public int run(ProcessStream process) throws CmdLineException { CONFIG.setupDecorateMethods(); Binding binding = CONFIG.getDefaultBinding(process, Collections.<String>emptyList(), runtime); GroovyShell shell = new GroovyShell(binding, CONFIG.getCompilerConfiguration()); CONFIG.setupDecorateMethods(); String script = String.format(SCRIPT_STUB, predicate); ThreadSet<?, ?, ?> set = (ThreadSet<?, ?, ?>) shell.run(script, "dumpling-script", Collections.emptyList()); set.toString(process.out(), porcelain ? Mode.MACHINE : Mode.HUMAN); process.err().printf("Threads: %d%n", set.size()); return set.isEmpty() ? 1 : 0; }  @Override String getName(); @Override String getDescription(); @Override int run(ProcessStream process);  }### Answer:
@Test public void cli() throws Exception { final String log = Util.asFile(Util.resource("jstack/producer-consumer.log")).getAbsolutePath(); run("grep", "thread.name == 'blocked_thread'", "--in", "threaddump:" + log); assertThat(this, succeeded()); assertThat(err.toString(), equalTo(String.format("Threads: 1%n"))); assertThat(out.toString(), containsString("\"blocked_thread\"")); assertThat(out.toString(), not(containsString("\"owning_thread\""))); run("grep", "false", "--in", "threaddump:" + log); assertThat(exitValue, equalTo(1)); assertThat(err.toString(), equalTo(String.format("Threads: 0%n"))); assertThat(out.toString(), not(containsString("\"blocked_thread\""))); assertThat(out.toString(), not(containsString("\"owning_thread\""))); run("grep", "--in", "threaddump:" + log); assertThat(exitValue, equalTo(-1)); }
@Test public void porcelain() throws Exception { final String log = Util.asFile(Util.resource("jstack/producer-consumer.log")).getAbsolutePath(); run("grep", "thread.status.blocked", "--in", "threaddump:" + log); assertThat(out.toString(), containsString("\"blocked_thread\" prio=10 tid=0x2ad39c16b800 nid=32297")); assertThat(out.toString(), containsString("- waiting to lock <0x4063a9378> (a hudson.model.Queue)")); run("grep", "thread.status.blocked", "--in", "threaddump:" + log, "--porcelain"); assertThat(out.toString(), containsString("\"blocked_thread\" prio=10 tid=0x00002ad39c16b800 nid=0x7e29")); assertThat(out.toString(), containsString("- waiting to lock <0x00000004063a9378> (a hudson.model.Queue)")); }
@Test public void hasHelp() { run("help", "grep"); assertThat(out.toString(), containsString("Thread to be examined in the predicate is named 'thread'")); }