/*
* Copyright © 2014 Cask Data, Inc.
*
* 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 co.cask.cdap.common.discovery;
import org.apache.twill.discovery.Discoverable;
import java.util.concurrent.TimeUnit;
/**
* An {@link EndpointStrategy} that make sure it picks an endpoint within the given
* timeout limit.
*/
public final class TimeLimitEndpointStrategy implements EndpointStrategy {
private final EndpointStrategy delegate;
private final long timeout;
private final TimeUnit timeoutUnit;
public TimeLimitEndpointStrategy(EndpointStrategy delegate, long timeout, TimeUnit timeoutUnit) {
this.delegate = delegate;
this.timeout = timeout;
this.timeoutUnit = timeoutUnit;
}
@Override
public Discoverable pick() {
Discoverable pick = delegate.pick();
try {
long count = 0;
while (pick == null && count++ < timeout) {
timeoutUnit.sleep(1);
pick = delegate.pick();
}
} catch (InterruptedException e) {
// Simply propagate the interrupt.
Thread.currentThread().interrupt();
}
return pick;
}
}