dwrnamespacehandler.java

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        }

    }

    /**
     * Parse the <code>&lt;dwr:init&gt;</code> elements
     */
    protected class InitDefinitionDecorator implements BeanDefinitionDecorator
    {
        public BeanDefinitionHolder decorate(Node parent, BeanDefinitionHolder definition, ParserContext parserContext)
        {           
            Map converters = new HashMap();
            Map creators = new HashMap();
            NodeList inits = parent.getChildNodes();
            for (int j = 0; j < inits.getLength(); j++)
            {
                Node node = inits.item(j);
                if (node.getNodeType() == Node.TEXT_NODE || node.getNodeType() == Node.COMMENT_NODE)
                {
                    continue;
                }

                Element child = (Element)inits.item(j);
                if (child.getNodeName().equals(ELEMENT_CREATOR))
                {
                    String id = child.getAttribute(ATTRIBUTE_ID);
                    String className = child.getAttribute(ATTRIBUTE_CLASS);
                    creators.put(id, className);
                }
                else if (child.getNodeName().equals(ELEMENT_CONVERTER))
                {
                    String id = child.getAttribute(ATTRIBUTE_ID);
                    String className = child.getAttribute(ATTRIBUTE_CLASS);
                    converters.put(id, className);
                }
                else
                {
                    throw new RuntimeException("An unknown sub node '" + child.getNodeName() + 
                            "' was found while parsing dwr:init");
                }
            }

            
            BeanDefinition configurator = registerSpringConfiguratorIfNecessary(parserContext.getRegistry());
            configurator.getPropertyValues().addPropertyValue("creatorTypes", creators);
            configurator.getPropertyValues().addPropertyValue("converterTypes", converters);

            return definition;
        }
    }

    
    /**
     * Uses the BeanDefinitionDecorator since we need access to the name of the parent definition??
     * Register the creatores: spring, new, null, scripted, jsf, struts, pageflow
     */
    protected class CreatorBeanDefinitionDecorator implements BeanDefinitionDecorator
    {
        
        public BeanDefinitionHolder decorate(Node node, BeanDefinitionHolder definition, ParserContext parserContext)
        {
            Element element = (Element) node;
            String javascript = element.getAttribute("javascript");
            String creatorType = element.getAttribute("type");

            BeanDefinitionBuilder creatorConfig = BeanDefinitionBuilder.rootBeanDefinition(CreatorConfig.class);
            
            // Configure "known" creators in the CreatorConfig. If unknown then just create the configuration
            // and leave it up DWR itself to decide if it's a valid creator type
            BeanDefinitionBuilder creator;
            Map params = new HashMap();
            
            if ("spring".equals(creatorType))
            {
                // TODO Refactor so that both spring creators use the same code...
                BeanDefinitionBuilder springCreator = BeanDefinitionBuilder.rootBeanDefinition(BeanCreator.class);
                
                springCreator.addPropertyValue("javascript", javascript);
                
                NodeList children = element.getChildNodes();
                for (int i = 0; i < children.getLength(); i++)
                {
                    Node childNode = children.item(i);
                    if (childNode.getNodeType() == Node.TEXT_NODE || childNode.getNodeType() == Node.COMMENT_NODE)
                    {
                        continue;
                    }
                    
                    Element child = (Element) childNode;
                    String paramName = child.getAttribute("name");
                    String value = child.getAttribute("value");
                    if ("beanName".equals(paramName) || "beanId".equals(paramName)) {
                        springCreator.addPropertyValue("beanId", value);
                    } else {
                        params.put(paramName, value);    
                    }
                }
                
                creatorConfig.addPropertyValue("creator", springCreator.getBeanDefinition());         
            }
            else if ("new".equals(creatorType))
            {
                creator = BeanDefinitionBuilder.rootBeanDefinition(NewCreator.class);
                creator.addPropertyValue("className", node.getAttributes().getNamedItem("class").getNodeValue());
                creator.addPropertyValue("javascript", javascript);
                creatorConfig.addPropertyValue("creator", creator.getBeanDefinition());
            }
            else if ("null".equals(creatorType))
            {
                creatorConfig.addPropertyValue("creatorType", "none");
                String className = element.getAttribute("class");
                if (className == null || "".equals(className)) 
                {
                    throw new BeanInitializationException("'class' is a required attribute for the declaration <dwr:creator type=\"null\"" + 
                            " javascript=\"" + javascript + "\" ... />");
                }
                params.put("class", className);
            }
            else if ("pageflow".equals(creatorType))
            {
                creatorConfig.addPropertyValue("creatorType", creatorType);
            }
            else if ("jsf".equals(creatorType) || "scripted".equals(creatorType) || "struts".equals(creatorType))
            {
                creatorConfig.addPropertyValue("creatorType", creatorType);
            }
            else
            {
                if (log.isDebugEnabled())
                {
                    log.debug("Looking up creator type '" + creatorType + "'");
                }
                // TODO We should delay the initialization of the creatorClass until after the bean 
                // definitions have been parsed.  
                BeanDefinition configurator = registerSpringConfiguratorIfNecessary(parserContext.getRegistry());
                PropertyValue registeredCreators = configurator.getPropertyValues().getPropertyValue("creatorTypes");
                Map registeredCreatorMap = (Map)registeredCreators.getValue();
                String creatorClass = (String)registeredCreatorMap.get(creatorType);
                if (creatorClass == null)
                {
                    // the creator type should have been registered
                    throw new UnsupportedOperationException("Type " + creatorType + " is not supported " + 
                            " or the custom creator has not been registered dwr:init");                    
                } 
                else 
                {
                    try 
                    {
                        Class clazz = Class.forName(creatorClass);
                        creator = BeanDefinitionBuilder.rootBeanDefinition(clazz);
                        creatorConfig.addPropertyValue("creator", creator.getBeanDefinition());
                        String className = element.getAttribute("class");
                        if (StringUtils.hasText(className))
                        {
                            params.put("class", className);
                        }
                    } 
                    catch (ClassNotFoundException ex) 
                    {
                        throw new FatalBeanException("ClassNotFoundException trying to register " +  
                                " creator '" + creatorClass +  "' for javascript type '" + javascript +"'. Check the " + 
                                " class in the classpath and that the creator is register in dwr:init", ex);
                    }
                }
            }

            registerCreator(parserContext.getRegistry(), javascript, creatorConfig, params, node.getChildNodes());

            return definition;
        }
    }

    protected class SignaturesBeanDefinitionDecorator implements BeanDefinitionDecorator
    {

        public BeanDefinitionHolder decorate(Node node, BeanDefinitionHolder definition, ParserContext parserContext)
        {
            BeanDefinitionRegistry registry = parserContext.getRegistry();
            BeanDefinition config = registerSpringConfiguratorIfNecessary(registry);

            StringBuffer sigtext = new StringBuffer();
            NodeList children = node.getChildNodes();
            for (int i = 0; i < children.getLength(); i++)
            {
                Node child = children.item(i);
                if (child.getNodeType() != Node.TEXT_NODE && child.getNodeType() != Node.CDATA_SECTION_NODE)
                {
                    log.warn("Ignoring illegal node type: " + child.getNodeType());
                    continue;
                }
                sigtext.append(child.getNodeValue());
            }

            config.getPropertyValues().addPropertyValue("signatures", sigtext.toString());

            return definition;
        }

    }

    protected Map lookupCreators(BeanDefinitionRegistry registry)
    {
        BeanDefinition config = registerSpringConfiguratorIfNecessary(registry);
        return (Map) config.getPropertyValues().getPropertyValue("creators").getValue();
    }

    protected Map lookupConverters(BeanDefinitionRegistry registry)
    {
        BeanDefinition config = registerSpringConfiguratorIfNecessary(registry);
        return (Map) config.getPropertyValues().getPropertyValue("converters").getValue();
    }

    protected final static String DEFAULT_SPRING_CONFIGURATOR_ID = "__dwrConfiguration";

    /**
     * The log stream
     */
    protected static final Logger log = Logger.getLogger(DwrNamespaceHandler.class);
    
    /*
     * The element names
     */
    private static final String ELEMENT_CONVERTER = "dwr:converter";
    
    private static final String ELEMENT_CREATOR = "dwr:creator";
    
    /*
     * The attribute names
     */
    private static final String ATTRIBUTE_ID = "id";

    private static final String ATTRIBUTE_CLASS = "class";
    
    
}