001/*
002 * Copyright 2002-2012 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 */
016
017package org.springframework.beans.factory.xml;
018
019import org.w3c.dom.Attr;
020import org.w3c.dom.Element;
021import org.w3c.dom.Node;
022
023import org.springframework.beans.MutablePropertyValues;
024import org.springframework.beans.factory.config.BeanDefinition;
025import org.springframework.beans.factory.config.BeanDefinitionHolder;
026import org.springframework.beans.factory.config.RuntimeBeanReference;
027import org.springframework.core.Conventions;
028import org.springframework.lang.Nullable;
029
030/**
031 * Simple {@code NamespaceHandler} implementation that maps custom attributes
032 * directly through to bean properties. An important point to note is that this
033 * {@code NamespaceHandler} does not have a corresponding schema since there
034 * is no way to know in advance all possible attribute names.
035 *
036 * <p>An example of the usage of this {@code NamespaceHandler} is shown below:
037 *
038 * <pre class="code">
039 * &lt;bean id=&quot;rob&quot; class=&quot;..TestBean&quot; p:name=&quot;Rob Harrop&quot; p:spouse-ref=&quot;sally&quot;/&gt;</pre>
040 *
041 * Here the '{@code p:name}' corresponds directly to the '{@code name}'
042 * property on class '{@code TestBean}'. The '{@code p:spouse-ref}'
043 * attributes corresponds to the '{@code spouse}' property and, rather
044 * than being the concrete value, it contains the name of the bean that will
045 * be injected into that property.
046 *
047 * @author Rob Harrop
048 * @author Juergen Hoeller
049 * @since 2.0
050 */
051public class SimplePropertyNamespaceHandler implements NamespaceHandler {
052
053        private static final String REF_SUFFIX = "-ref";
054
055
056        @Override
057        public void init() {
058        }
059
060        @Override
061        @Nullable
062        public BeanDefinition parse(Element element, ParserContext parserContext) {
063                parserContext.getReaderContext().error(
064                                "Class [" + getClass().getName() + "] does not support custom elements.", element);
065                return null;
066        }
067
068        @Override
069        public BeanDefinitionHolder decorate(Node node, BeanDefinitionHolder definition, ParserContext parserContext) {
070                if (node instanceof Attr) {
071                        Attr attr = (Attr) node;
072                        String propertyName = parserContext.getDelegate().getLocalName(attr);
073                        String propertyValue = attr.getValue();
074                        MutablePropertyValues pvs = definition.getBeanDefinition().getPropertyValues();
075                        if (pvs.contains(propertyName)) {
076                                parserContext.getReaderContext().error("Property '" + propertyName + "' is already defined using " +
077                                                "both <property> and inline syntax. Only one approach may be used per property.", attr);
078                        }
079                        if (propertyName.endsWith(REF_SUFFIX)) {
080                                propertyName = propertyName.substring(0, propertyName.length() - REF_SUFFIX.length());
081                                pvs.add(Conventions.attributeNameToPropertyName(propertyName), new RuntimeBeanReference(propertyValue));
082                        }
083                        else {
084                                pvs.add(Conventions.attributeNameToPropertyName(propertyName), propertyValue);
085                        }
086                }
087                return definition;
088        }
089
090}