/*
 * Copyright (c) 2014 Spotify AB.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package com.spotify.helios;

import java.util.concurrent.Callable;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;

import static com.google.common.base.Throwables.propagate;
import static com.google.common.base.Throwables.propagateIfInstanceOf;
import static java.lang.System.nanoTime;

public class Polling {

  public static <T> T await(final long timeout, final TimeUnit timeUnit, final Callable<T> callable)
      throws Exception {
    final long deadline = nanoTime() + timeUnit.toNanos(timeout);
    while (nanoTime() < deadline) {
      final T value = callable.call();
      if (value != null) {
        return value;
      }
      Thread.sleep(500);
    }
    throw new TimeoutException();
  }

  public static <T> T awaitUnchecked(final long timeout, final TimeUnit timeUnit,
                                     final Callable<T> callable) throws TimeoutException {
    try {
      return await(timeout, timeUnit, callable);
    } catch (Throwable e) {
      propagateIfInstanceOf(e, TimeoutException.class);
      throw propagate(e);
    }
  }
}

@@ -1293,24 +1293,656 @@
 (500);%0A    %7D
+%0A%0A    final String msg = String.format(%0A        %22The callable %25s defined in %25s failed to return anything after %25d ms%22,%0A        callable.getClass().getName(),%0A        // since this is just test code, include the class/method/line number that called this%0A        // method  to help diagnose where the failure was since most Callables will just be%0A        // anonymous classes.%0A        // The class that called this method will be the 3rd element in the array - the first is the%0A        // getStackTrace method and the second is Polling.await%0A        Thread.currentThread().getStackTrace()%5B2%5D,%0A        timeUnit.toMillis(timeout)%0A    );
 %0A    throw n
@@ -1961,16 +1961,19 @@
 ception(
+msg
 );%0A  %7D%0A%0A

make Polling.await exception messages friendlier