/*
* Copyright (c) 2002-2012 Alibaba Group Holding Limited.
* All rights reserved.
*
* 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.alibaba.citrus.service.pipeline.impl.valve;
import static com.alibaba.citrus.springext.util.SpringExtUtil.*;
import static com.alibaba.citrus.util.Assert.*;
import com.alibaba.citrus.service.pipeline.Condition;
import com.alibaba.citrus.service.pipeline.PipelineContext;
import com.alibaba.citrus.service.pipeline.PipelineInvocationHandle;
import com.alibaba.citrus.service.pipeline.support.AbstractValveDefinitionParser;
import com.alibaba.citrus.util.ToStringBuilder;
import com.alibaba.citrus.util.ToStringBuilder.MapBuilder;
import org.springframework.beans.factory.support.BeanDefinitionBuilder;
import org.springframework.beans.factory.xml.ParserContext;
import org.w3c.dom.Element;
/**
* 当条件满足时，执行循环体。
*
* @author Michael Zhou
*/
public class WhileLoopValve extends LoopValve {
private Condition condition;
public Condition getCondition() {
return condition;
}
public void setCondition(Condition condition) {
this.condition = condition;
}
@Override
protected void init() throws Exception {
super.init();
assertNotNull(condition, "no condition");
}
@Override
public void invoke(PipelineContext pipelineContext) throws Exception {
assertInitialized();
PipelineInvocationHandle handle = initLoop(pipelineContext);
while (condition.isSatisfied(handle)) { // 注意：condition的上下文为handle而非当前pipelineContext
invokeBody(handle);
if (handle.isBroken()) {
break;
}
}
pipelineContext.invokeNext();
}
@Override
public String toString() {
MapBuilder mb = new MapBuilder();
mb.append("condition", condition);
mb.append("loopBody", getLoopBody());
return new ToStringBuilder().append("WhileLoopValve").append(mb).toString();
}
public static class DefinitionParser extends AbstractValveDefinitionParser<WhileLoopValve> {
@Override
protected final void doParse(Element element, ParserContext parserContext, BeanDefinitionBuilder builder) {
attributesToProperties(element, builder, "maxLoopCount", "loopCounterName");
builder.addPropertyValue("loopBody", parsePipeline(element, parserContext));
Object condition = parseCondition(element, parserContext, builder);
if (condition != null) {
builder.addPropertyValue("condition", condition);
}
}
}
}