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1   /*
2    * Copyright 2006-2008 the original author or authors.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package org.springframework.batch.core.configuration.xml;
17  
18  import java.util.Collection;
19  
20  import org.springframework.beans.factory.config.BeanDefinition;
21  import org.springframework.beans.factory.config.RuntimeBeanReference;
22  import org.springframework.beans.factory.support.BeanDefinitionBuilder;
23  import org.springframework.beans.factory.xml.ParserContext;
24  import org.w3c.dom.Element;
25  
26  /**
27   * Internal parser for the <decision/> elements inside a job. A decision
28   * element references a bean definition for a 
29   * {@link org.springframework.batch.core.job.flow.JobExecutionDecider} 
30   * and goes on to list a set of transitions to other states with <next
31   * on="pattern" to="stepName"/>. Used by the {@link JobParser}.
32   * 
33   * @see JobParser
34   * 
35   * @author Dave Syer
36   * 
37   */
38  public class DecisionParser {
39  
40  	/**
41  	 * Parse the decision and turn it into a list of transitions.
42  	 * 
43  	 * @param element the <decision/gt; element to parse
44  	 * @param parserContext the parser context for the bean factory
45  	 * @return a collection of bean definitions for 
46  	 * {@link org.springframework.batch.core.job.flow.support.StateTransition}
47  	 * instances objects
48  	 */
49  	public Collection<BeanDefinition> parse(Element element, ParserContext parserContext) {
50  
51  		String refAttribute = element.getAttribute("decider");
52  		String idAttribute = element.getAttribute("id");
53  
54  		BeanDefinitionBuilder stateBuilder = 
55  			BeanDefinitionBuilder.genericBeanDefinition("org.springframework.batch.core.job.flow.support.state.DecisionState");
56  		stateBuilder.addConstructorArgValue(new RuntimeBeanReference(refAttribute));
57  		stateBuilder.addConstructorArgValue(idAttribute);
58  		return InlineFlowParser.getNextElements(parserContext, stateBuilder.getBeanDefinition(), element);
59  
60  	}
61  }