Example usage for java.util Queue peek

Introduction

In this page you can find the example usage for java.util Queue peek.

Prototype

E peek();

Source Link

Document

Retrieves, but does not remove, the head of this queue, or returns null if this queue is empty.

Usage

From source file:pt.webdetails.cda.cache.scheduler.CacheActivator.java

public static void reschedule(Queue<CachedQuery> queue) {
    CachedQuery q = queue.peek();

    Date dueAt = (q != null) ? q.getNextExecution() : null;
    IPentahoSession session = new StandaloneSession(JOB_GROUP);
    Scheduler sched = QuartzSystemListener.getSchedulerInstance();

    SchedulerHelper.deleteJob(session, JOB_ACTION, JOB_GROUP);
    SchedulerHelper.createSimpleTriggerJob(session, "system", "cda/actions", JOB_ACTION, TRIGGER_NAME,
            JOB_GROUP, "", dueAt, null, 0, 0);
}

From source file:test.jamocha.languages.clips.BindTest.java

@Test
public void testTranslateRHSBind() throws ParseException {
    final Network network = new Network();
    final ByteArrayOutputStream out = initializeAppender(network);
    run(network, "(unwatch all)\n");
    {//from w  ww  .j a  v a2s .  co m
        final Pair<Queue<Object>, Queue<Warning>> returnValues = run(network,
                "(deftemplate f1 (slot s1 (type INTEGER)))\n"
                        + "(defrule r1 (f1 (s1 ?x)) => (bind ?y (+ ?x 2)) (assert (f1 (s1 ?y))) ) \n");
        assertThat(returnValues.getLeft(), empty());
        assertThat(returnValues.getRight(), empty());
        assertThat(out.toString(), isEmptyString());
        out.reset();
    }
    {
        final Pair<Queue<Object>, Queue<Warning>> returnValues = run(network, "(assert (f1 (s1 5)))");
        final Queue<Object> left = returnValues.getLeft();
        assertThat(left, hasSize(1));
        assertThat(left.peek(), instanceOf(String.class));
        assertThat(returnValues.getRight(), empty());
        assertThat(out.toString(), isEmptyString());
        out.reset();
    }
    {
        final Pair<Queue<Object>, Queue<Warning>> returnValues = run(network, "(watch facts)");
        assertThat(returnValues.getLeft(), empty());
        assertThat(returnValues.getRight(), empty());
        assertThat(out.toString(), isEmptyString());
        out.reset();
    }
    {
        final Pair<Queue<Object>, Queue<Warning>> returnValues = run(network, "(run 1)");
        assertThat(returnValues.getLeft(), empty());
        assertThat(returnValues.getRight(), empty());
        final String output = out.toString();
        assertThat(output, not(isEmptyString()));
        final String[] lines = output.split(LINE_SEPARATOR);
        assertThat(lines, arrayWithSize(1));
        assertEquals("==> f-3\t(f1 (s1 7))", lines[0]);
        out.reset();
    }
}