org.springframework.integration.scheduling.PollSkipAdvice Maven / Gradle / Ivy
/*
* Copyright 2014-2019 the original author or authors.
*
* 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
*
* https://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.springframework.integration.scheduling;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* An advice that can be added to a poller's advice chain that determines
* whether a poll should be skipped or not. May be used to temporarily suspend
* polling when some downstream condition exists in the flow.
*
* @author Gary Russell
* @since 4.1
*
*/
public class PollSkipAdvice implements MethodInterceptor {
private static final Log logger = LogFactory.getLog(PollSkipAdvice.class);
private final PollSkipStrategy pollSkipStrategy;
public PollSkipAdvice() {
this(new DefaultPollSkipStrategy());
}
public PollSkipAdvice(PollSkipStrategy strategy) {
this.pollSkipStrategy = strategy;
}
@Override
public Object invoke(MethodInvocation invocation) throws Throwable {
if ("call".equals(invocation.getMethod().getName()) && this.pollSkipStrategy.skipPoll()) {
if (logger.isDebugEnabled()) {
logger.debug("Skipping poll because "
+ this.pollSkipStrategy.getClass().getName()
+ ".skipPoll() returned true");
}
return null;
}
else {
return invocation.proceed();
}
}
private static final class DefaultPollSkipStrategy implements PollSkipStrategy {
DefaultPollSkipStrategy() {
super();
}
@Override
public boolean skipPoll() {
return false;
}
}
}