| /** |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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 org.apache.camel.component.disruptor; |
| |
| import java.util.concurrent.CountDownLatch; |
| import java.util.concurrent.TimeUnit; |
| |
| import com.lmax.disruptor.InsufficientCapacityException; |
| |
| import org.apache.camel.AsyncCallback; |
| import org.apache.camel.Exchange; |
| import org.apache.camel.ExchangeTimedOutException; |
| import org.apache.camel.WaitForTaskToComplete; |
| import org.apache.camel.impl.DefaultAsyncProducer; |
| import org.apache.camel.support.SynchronizationAdapter; |
| import org.apache.camel.util.ExchangeHelper; |
| |
| /** |
| * A Producer for the Disruptor component. |
| */ |
| public class DisruptorProducer extends DefaultAsyncProducer { |
| |
| private final WaitForTaskToComplete waitForTaskToComplete; |
| private final long timeout; |
| |
| private final DisruptorEndpoint endpoint; |
| private boolean blockWhenFull; |
| |
| public DisruptorProducer(final DisruptorEndpoint endpoint, |
| final WaitForTaskToComplete waitForTaskToComplete, |
| final long timeout, boolean blockWhenFull) { |
| super(endpoint); |
| this.waitForTaskToComplete = waitForTaskToComplete; |
| this.timeout = timeout; |
| this.endpoint = endpoint; |
| this.blockWhenFull = blockWhenFull; |
| } |
| |
| @Override |
| public DisruptorEndpoint getEndpoint() { |
| return endpoint; |
| } |
| |
| @Override |
| protected void doStart() throws Exception { |
| getEndpoint().onStarted(this); |
| } |
| |
| @Override |
| protected void doStop() throws Exception { |
| getEndpoint().onStopped(this); |
| } |
| |
| @Override |
| public boolean process(final Exchange exchange, final AsyncCallback callback) { |
| WaitForTaskToComplete wait = waitForTaskToComplete; |
| if (exchange.getProperty(Exchange.ASYNC_WAIT) != null) { |
| wait = exchange.getProperty(Exchange.ASYNC_WAIT, WaitForTaskToComplete.class); |
| } |
| |
| if (wait == WaitForTaskToComplete.Always |
| || (wait == WaitForTaskToComplete.IfReplyExpected && ExchangeHelper.isOutCapable(exchange))) { |
| |
| // do not handover the completion as we wait for the copy to complete, and copy its result back when it done |
| final Exchange copy = prepareCopy(exchange, false); |
| |
| // latch that waits until we are complete |
| final CountDownLatch latch = new CountDownLatch(1); |
| |
| // we should wait for the reply so install a on completion so we know when its complete |
| copy.addOnCompletion(new SynchronizationAdapter() { |
| @Override |
| public void onDone(final Exchange response) { |
| // check for timeout, which then already would have invoked the latch |
| if (latch.getCount() == 0) { |
| if (log.isTraceEnabled()) { |
| log.trace("{}. Timeout occurred so response will be ignored: {}", this, |
| response.hasOut() ? response.getOut() : response.getIn()); |
| } |
| } else { |
| if (log.isTraceEnabled()) { |
| log.trace("{} with response: {}", this, |
| response.hasOut() ? response.getOut() : response.getIn()); |
| } |
| try { |
| ExchangeHelper.copyResults(exchange, response); |
| } finally { |
| // always ensure latch is triggered |
| latch.countDown(); |
| } |
| } |
| } |
| |
| @Override |
| public boolean allowHandover() { |
| // do not allow handover as we want to seda producer to have its completion triggered |
| // at this point in the routing (at this leg), instead of at the very last (this ensure timeout is honored) |
| return false; |
| } |
| |
| @Override |
| public String toString() { |
| return "onDone at endpoint: " + endpoint; |
| } |
| }); |
| |
| doPublish(copy); |
| |
| if (timeout > 0) { |
| if (log.isTraceEnabled()) { |
| log.trace("Waiting for task to complete using timeout (ms): {} at [{}]", timeout, |
| endpoint.getEndpointUri()); |
| } |
| // lets see if we can get the task done before the timeout |
| boolean done = false; |
| try { |
| done = latch.await(timeout, TimeUnit.MILLISECONDS); |
| } catch (InterruptedException e) { |
| // ignore |
| } |
| if (!done) { |
| // Remove timed out Exchange from disruptor endpoint. |
| |
| // We can't actually remove a published exchange from an active Disruptor. |
| // Instead we prevent processing of the exchange by setting a Property on the exchange and the value |
| // would be an AtomicBoolean. This is set by the Producer and the Consumer would look up that Property and |
| // check the AtomicBoolean. If the AtomicBoolean says that we are good to proceed, it will process the |
| // exchange. If false, it will simply disregard the exchange. |
| // But since the Property map is a Concurrent one, maybe we don't need the AtomicBoolean. Check with Simon. |
| // Also check the TimeoutHandler of the new Disruptor 3.0.0, consider making the switch to the latest version. |
| exchange.setProperty(DisruptorEndpoint.DISRUPTOR_IGNORE_EXCHANGE, true); |
| |
| exchange.setException(new ExchangeTimedOutException(exchange, timeout)); |
| |
| // count down to indicate timeout |
| latch.countDown(); |
| } |
| } else { |
| if (log.isTraceEnabled()) { |
| log.trace("Waiting for task to complete (blocking) at [{}]", endpoint.getEndpointUri()); |
| } |
| // no timeout then wait until its done |
| try { |
| latch.await(); |
| } catch (InterruptedException e) { |
| // ignore |
| } |
| } |
| } else { |
| // no wait, eg its a InOnly then just publish to the ringbuffer and return |
| // handover the completion so its the copy which performs that, as we do not wait |
| final Exchange copy = prepareCopy(exchange, true); |
| doPublish(copy); |
| } |
| |
| // we use OnCompletion on the Exchange to callback and wait for the Exchange to be done |
| // so we should just signal the callback we are done synchronously |
| callback.done(true); |
| return true; |
| } |
| |
| private void doPublish(Exchange exchange) { |
| log.trace("Publishing Exchange to disruptor ringbuffer: {}", exchange); |
| |
| try { |
| if (blockWhenFull) { |
| endpoint.publish(exchange); |
| } else { |
| endpoint.tryPublish(exchange); |
| } |
| } catch (DisruptorNotStartedException e) { |
| throw new IllegalStateException("Disruptor was not started", e); |
| } catch (InsufficientCapacityException e) { |
| throw new IllegalStateException("Disruptors ringbuffer was full", e); |
| } |
| } |
| |
| |
| private Exchange prepareCopy(final Exchange exchange, final boolean handover) { |
| // use a new copy of the exchange to route async |
| final Exchange copy = ExchangeHelper.createCorrelatedCopy(exchange, handover); |
| // set a new from endpoint to be the disruptor |
| copy.setFromEndpoint(endpoint); |
| return copy; |
| } |
| } |