/*
* 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.nutch.webapp.common;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
import java.lang.ClassLoader;
/**
* This class is responsible for parsing web.xml definitions from plugins (put
* there by jspc when precompiling jsp files).
*
* Extracted information is used at runtime when dispatching requests targetted
* to jsp resources to the precompiled servlet classes.
*/
public class WebAppModule {
HashMap servlets;
List urlPatterns;
ClassLoader loader = null;
HashMap servletObjects = new HashMap();
private ServletConfig servletConfig;
/**
* Construct new WebAppModule
*
* @param input
* ionputstream to web.xml type of document
*/
public WebAppModule(InputStream input) {
loader = Thread.currentThread().getContextClassLoader();
init(input);
}
public void init(InputStream input) {
Document doc;
servlets = new HashMap();
urlPatterns = new ArrayList();
if (input != null) {
try {
doc = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(
input);
parse(doc);
} catch (SAXException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} catch (ParserConfigurationException e) {
e.printStackTrace();
}
}
loadServlets();
}
public void loadServlets() {
Iterator i = getPaths().iterator();
while (i.hasNext()) {
String key = (String) i.next();
String servletName = (String) servlets.get(key);
HttpServlet servletObject;
Class servletClass;
try {
servletClass = loader.loadClass(servletName);
servletObject = (HttpServlet) servletClass.newInstance();
servletObject.init(servletConfig);
servletObjects.put(key, servletObject);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (InstantiationException e) {
e.printStackTrace();
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (ServletException e) {
e.printStackTrace();
}
}
}
public WebAppModule(ClassLoader loader, ServletConfig config) {
servletConfig = config;
this.loader = loader;
init(loader.getResourceAsStream("META-INF/jsp-servlet-mappings.xml"));
}
/**
* Get jsp paths available
*
* @return
*/
public List getPaths() {
return urlPatterns;
}
public Map getMappings() {
return servlets;
}
/**
* Return Servlet name for path or null if non existing
*
* @param path
* @return
*/
public String getServletName(String path) {
return (String) servlets.get(path);
}
public void parse(Document doc) {
Element root = doc.getDocumentElement();
NodeList mappings = root.getElementsByTagName("servlet-mapping");
for (int i = 0; i < mappings.getLength(); i++) {
Element mapping = (Element) mappings.item(i);
Element servlet = (Element) mapping.getElementsByTagName("servlet-name")
.item(0);
Element pattern = (Element) mapping.getElementsByTagName("url-pattern")
.item(0);
String servletName = servlet.getTextContent().trim();
String urlPattern = pattern.getTextContent().trim();
servlets.put(urlPattern, servletName);
urlPatterns.add(urlPattern);
}
}
/**
* Dispatches request to precompiled jsp
*
* @param relPath
* @param request
* @param response
*/
public void dispatch(String relPath, HttpServletRequest request,
HttpServletResponse response) {
HttpServlet servletObject;
if (servletObjects.containsKey(relPath)) {
servletObject = (HttpServlet) servletObjects.get(relPath);
} else {
// servlet not found??
return;
}
try {
servletObject.service(request, response);
} catch (ServletException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}