Struts example source code file (DynAttribsTest.java)

This example Struts source code file (DynAttribsTest.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Struts tags/keywords

class, dom, dynamicattributes, dynamicattributes, dynattribstest, element, element, exception, file, instantiationexception, jsp, network, nodelist, nodelist, parser, servlet, string, string, strutstestcase, xml

The Struts DynAttribsTest.java source code

/*
 * $Id$
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.struts2.views.jsp;

import java.io.File;
import java.net.URL;

import javax.servlet.jsp.tagext.DynamicAttributes;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;

import org.apache.struts2.StrutsTestCase;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

/**
 * DynAttribsTest test case.
 *
 * When a tag is declared in a TLD file as 
 * <dynamic-attributes>true
 * then the tag-class must implement the 
 * javax.servlet.jsp.tagext.DynamicAttributes interface.
 * If a tag's class does not implement this interface, 
 * the the application server will treat the tag as unsafe.
 * 
 * This test parses the struts-tag.tld file and checks
 * that each of the tags defined as accepting dynamic 
 * attributes implements DynamicAttributes.
 */
public class DynAttribsTest extends StrutsTestCase {
	
	private Document doc ;
	
    protected void setUp() throws Exception {
        super.setUp();
        
        // prepare to parse the TLD file using DOM
        DocumentBuilderFactory factory 
            = DocumentBuilderFactory.newInstance();

        DocumentBuilder builder ;
        try {
            builder = factory.newDocumentBuilder();
        }
        catch (Exception e) {
            e.printStackTrace();
            return;
        }
        
        URL s2Url = this.getClass().getResource("/META-INF/struts-tags.tld");
        if (s2Url == null ) {
            fail("unable to find struts-tags.tld");
        }
        File tldFile = new File(s2Url.toURI());
        doc = builder.parse(tldFile);
        
    }
    
    public void testHasDynParamInterface() {
        Element rootElem = doc.getDocumentElement();
        NodeList nl = rootElem.getElementsByTagName("tag");
        
        if(nl != null && nl.getLength() > 0) {
            
            for(int i = 0 ; i < nl.getLength();i++) {
        
                Element tag = (Element)nl.item(i);
                
                // for each tag, get the class name
                // and dynamic-attributes value
                NodeList tagClassNodes 
                    = tag.getElementsByTagName("tag-class");
                
                Element tagClassElement 
                    = (Element)tagClassNodes.item(0);
                String clazzName 
                    = tagClassElement.getFirstChild().getNodeValue();
                
                NodeList dynAttribsNodeList 
                    = tag.getElementsByTagName("dynamic-attributes");
                
                // skip if not marked as dynamic-attributes=true
                if (dynAttribsNodeList.getLength() < 1) {
                    continue;
                }
                
                Element dynAttribsElement 
                    = (Element)dynAttribsNodeList.item(0);
                
                String isDynAttribs 
                    = dynAttribsElement.getFirstChild().getNodeValue();
                
                if (isDynAttribs == null ) {
                    continue;
                }
                
                if (! isDynAttribs.equalsIgnoreCase("true") ) {
                    continue;
                }
                
                // load the class using reflection
                Class clazz = null;
                
                try {
                    clazz = Class.forName(clazzName);
                }
                catch (ClassNotFoundException e){
                    fail("unable to load class");
                    return;
                }
                
                // instantiate class
                Object o = null;
                try {
                    o = clazz.newInstance();
                } catch (InstantiationException e) {
                    e.printStackTrace();
                } catch (IllegalAccessException e) {
                    e.printStackTrace();
                }
                
                boolean hasDynAttribs = o instanceof DynamicAttributes;
                
                String failMsg = "Class - " + clazzName + " does not implement the DynamicAttributes interface";
                assertTrue(failMsg, hasDynAttribs);
            
            }
        }
    }
}