001/*
002 * Copyright 2013-2014 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.springframework.batch.core.jsr.configuration.xml;
017
018import java.util.List;
019
020import org.springframework.batch.core.jsr.configuration.support.BatchArtifactType;
021import org.springframework.beans.factory.config.BeanDefinition;
022import org.springframework.beans.factory.config.RuntimeBeanReference;
023import org.springframework.beans.factory.parsing.CompositeComponentDefinition;
024import org.springframework.beans.factory.support.AbstractBeanDefinition;
025import org.springframework.beans.factory.support.BeanDefinitionBuilder;
026import org.springframework.beans.factory.support.BeanDefinitionRegistry;
027import org.springframework.beans.factory.support.ManagedList;
028import org.springframework.beans.factory.xml.ParserContext;
029import org.springframework.util.xml.DomUtils;
030import org.w3c.dom.Element;
031
032/**
033 * Parses the various listeners defined in JSR-352.  Current state assumes
034 * the ref attributes point to implementations of Spring Batch interfaces
035 * and not JSR interfaces
036 *
037 * @author Michael Minella
038 * @author Chris Schaefer
039 * @since 3.0
040 */
041public class ListenerParser {
042        private static final String REF_ATTRIBUTE = "ref";
043        private static final String LISTENER_ELEMENT = "listener";
044        private static final String LISTENERS_ELEMENT = "listeners";
045        private static final String SCOPE_STEP = "step";
046        private static final String SCOPE_JOB = "job";
047
048        private Class<?> listenerType;
049        private String propertyKey;
050
051        public ListenerParser(Class<?> listenerType, String propertyKey) {
052                this.propertyKey = propertyKey;
053                this.listenerType = listenerType;
054        }
055
056        public void parseListeners(Element element, ParserContext parserContext, AbstractBeanDefinition bd, String stepName) {
057                ManagedList<AbstractBeanDefinition> listeners = parseListeners(element, parserContext, stepName);
058
059                if(listeners.size() > 0) {
060                        bd.getPropertyValues().add(propertyKey, listeners);
061                }
062        }
063
064        public void parseListeners(Element element, ParserContext parserContext, BeanDefinitionBuilder builder) {
065                ManagedList<AbstractBeanDefinition> listeners = parseListeners(element, parserContext, "");
066
067                if(listeners.size() > 0) {
068                        builder.addPropertyValue(propertyKey, listeners);
069                }
070        }
071
072        private ManagedList<AbstractBeanDefinition> parseListeners(Element element, ParserContext parserContext, String stepName) {
073                List<Element> listenersElements = DomUtils.getChildElementsByTagName(element, LISTENERS_ELEMENT);
074
075                ManagedList<AbstractBeanDefinition> listeners = new ManagedList<AbstractBeanDefinition>();
076
077                if (listenersElements.size() == 1) {
078                        Element listenersElement = listenersElements.get(0);
079                        CompositeComponentDefinition compositeDef = new CompositeComponentDefinition(listenersElement.getTagName(),
080                                        parserContext.extractSource(element));
081                        parserContext.pushContainingComponent(compositeDef);
082                        listeners.setMergeEnabled(false);
083                        List<Element> listenerElements = DomUtils.getChildElementsByTagName(listenersElement, LISTENER_ELEMENT);
084                        for (Element listenerElement : listenerElements) {
085                                String beanName = listenerElement.getAttribute(REF_ATTRIBUTE);
086
087                                BeanDefinitionBuilder bd = BeanDefinitionBuilder.genericBeanDefinition(listenerType);
088                                bd.addPropertyValue("delegate", new RuntimeBeanReference(beanName));
089
090                                applyListenerScope(beanName, parserContext.getRegistry());
091
092                                listeners.add(bd.getBeanDefinition());
093
094                                new PropertyParser(beanName, parserContext, getBatchArtifactType(stepName), stepName).parseProperties(listenerElement);
095                        }
096                        parserContext.popAndRegisterContainingComponent();
097                }
098                else if (listenersElements.size() > 1) {
099                        parserContext.getReaderContext().error(
100                                        "The '<listeners/>' element may not appear more than once in a single " + element.getLocalName(), element);
101                }
102
103                return listeners;
104        }
105
106        protected void applyListenerScope(String beanName, BeanDefinitionRegistry beanDefinitionRegistry) {
107                BeanDefinition beanDefinition = getListenerBeanDefinition(beanName, beanDefinitionRegistry);
108                beanDefinition.setScope(getListenerScope());
109                beanDefinition.setLazyInit(isLazyInit());
110
111                if (!beanDefinitionRegistry.containsBeanDefinition(beanName)) {
112                        beanDefinitionRegistry.registerBeanDefinition(beanName, beanDefinition);
113                }
114        }
115
116        private BeanDefinition getListenerBeanDefinition(String beanName, BeanDefinitionRegistry beanDefinitionRegistry) {
117                if (beanDefinitionRegistry.containsBeanDefinition(beanName)) {
118                        return beanDefinitionRegistry.getBeanDefinition(beanName);
119                }
120
121                return BeanDefinitionBuilder.genericBeanDefinition(beanName).getBeanDefinition();
122        }
123
124        private boolean isLazyInit() {
125                return listenerType == JsrJobListenerFactoryBean.class;
126        }
127
128        private String getListenerScope() {
129                if (listenerType == JsrJobListenerFactoryBean.class) {
130                        return SCOPE_JOB;
131                }
132
133                return SCOPE_STEP;
134        }
135
136        private BatchArtifactType getBatchArtifactType(String stepName) {
137                return (stepName != null && !"".equals(stepName)) ? BatchArtifactType.STEP_ARTIFACT
138                                : BatchArtifactType.ARTIFACT;
139        }
140}