Java tutorial
/* * $Id: StrutsUtil.java 758258 2009-03-25 13:50:03Z musachy $ * * 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.util; import java.io.IOException; import java.io.PrintWriter; import java.io.StringWriter; import java.io.UnsupportedEncodingException; import java.net.URLEncoder; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; import java.util.Hashtable; import java.util.Iterator; import java.util.List; import java.util.Map; import javax.servlet.RequestDispatcher; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpServletResponseWrapper; import org.apache.commons.lang.StringEscapeUtils; import org.apache.struts2.views.jsp.ui.OgnlTool; import org.apache.struts2.views.util.UrlHelper; import com.opensymphony.xwork2.ActionContext; import com.opensymphony.xwork2.ObjectFactory; import com.opensymphony.xwork2.inject.Container; import com.opensymphony.xwork2.util.ValueStack; import com.opensymphony.xwork2.util.logging.Logger; import com.opensymphony.xwork2.util.logging.LoggerFactory; /** * Struts base utility class, for use in Velocity and Freemarker templates * */ public class StrutsUtil { protected static final Logger LOG = LoggerFactory.getLogger(StrutsUtil.class); protected HttpServletRequest request; protected HttpServletResponse response; protected Map classes = new Hashtable(); protected OgnlTool ognl; protected ValueStack stack; public StrutsUtil(ValueStack stack, HttpServletRequest request, HttpServletResponse response) { this.stack = stack; this.request = request; this.response = response; this.ognl = ((Container) stack.getContext().get(ActionContext.CONTAINER)).getInstance(OgnlTool.class); } public Object bean(Object aName) throws Exception { String name = aName.toString(); Class c = (Class) classes.get(name); if (c == null) { c = ClassLoaderUtils.loadClass(name, StrutsUtil.class); classes.put(name, c); } return ObjectFactory.getObjectFactory().buildBean(c, stack.getContext()); } public boolean isTrue(String expression) { Boolean retVal = (Boolean) stack.findValue(expression, Boolean.class); if (retVal == null) { return false; } return retVal.booleanValue(); } public Object findString(String name) { return stack.findValue(name, String.class); } public String include(Object aName) throws Exception { return include(aName, request, response); } /** * @deprecated the request and response are stored in this util class, please use include(string) */ public String include(Object aName, HttpServletRequest aRequest, HttpServletResponse aResponse) throws Exception { try { RequestDispatcher dispatcher = aRequest.getRequestDispatcher(aName.toString()); if (dispatcher == null) { throw new IllegalArgumentException("Cannot find included file " + aName); } ResponseWrapper responseWrapper = new ResponseWrapper(aResponse); dispatcher.include(aRequest, responseWrapper); return responseWrapper.getData(); } catch (Exception e) { e.printStackTrace(); throw e; } } public String urlEncode(String s) { try { return URLEncoder.encode(s, "UTF-8"); } catch (UnsupportedEncodingException e) { return s; } } public String buildUrl(String url) { return UrlHelper.buildUrl(url, request, response, null); } public Object findValue(String expression, String className) throws ClassNotFoundException { return stack.findValue(expression, Class.forName(className)); } public String getText(String text) { return (String) stack.findValue("getText('" + text + "')"); } /* * @return the url ContextPath. An empty string if one does not exist. */ public String getContext() { return (request == null) ? "" : request.getContextPath(); } /** * the selectedList objects are matched to the list.listValue * <p/> * listKey and listValue are optional, and if not provided, the list item is used * * @param selectedList the name of the action property * that contains the list of selected items * or single item if its not an array or list * @param list the name of the action property * that contains the list of selectable items * @param listKey an ognl expression that is exaluated relative to the list item * to use as the key of the ListEntry * @param listValue an ognl expression that is exaluated relative to the list item * to use as the value of the ListEntry * @return a List of ListEntry */ public List makeSelectList(String selectedList, String list, String listKey, String listValue) { List selectList = new ArrayList(); Collection selectedItems = null; Object i = stack.findValue(selectedList); if (i != null) { if (i.getClass().isArray()) { selectedItems = Arrays.asList((Object[]) i); } else if (i instanceof Collection) { selectedItems = (Collection) i; } else { // treat it is a single item selectedItems = new ArrayList(); selectedItems.add(i); } } Collection items = (Collection) stack.findValue(list); if (items != null) { for (Iterator iter = items.iterator(); iter.hasNext();) { Object element = (Object) iter.next(); Object key = null; if ((listKey == null) || (listKey.length() == 0)) { key = element; } else { key = ognl.findValue(listKey, element); } Object value = null; if ((listValue == null) || (listValue.length() == 0)) { value = element; } else { value = ognl.findValue(listValue, element); } boolean isSelected = false; if ((value != null) && (selectedItems != null) && selectedItems.contains(value)) { isSelected = true; } selectList.add(new ListEntry(key, value, isSelected)); } } return selectList; } public int toInt(long aLong) { return (int) aLong; } public long toLong(int anInt) { return (long) anInt; } public long toLong(String aLong) { if (aLong == null) { return 0; } return Long.parseLong(aLong); } public String toString(long aLong) { return Long.toString(aLong); } public String toString(int anInt) { return Integer.toString(anInt); } static class ResponseWrapper extends HttpServletResponseWrapper { StringWriter strout; PrintWriter writer; ServletOutputStream sout; ResponseWrapper(HttpServletResponse aResponse) { super(aResponse); strout = new StringWriter(); sout = new ServletOutputStreamWrapper(strout); writer = new PrintWriter(strout); } public String getData() { writer.flush(); return strout.toString(); } public ServletOutputStream getOutputStream() { return sout; } public PrintWriter getWriter() throws IOException { return writer; } } static class ServletOutputStreamWrapper extends ServletOutputStream { StringWriter writer; ServletOutputStreamWrapper(StringWriter aWriter) { writer = aWriter; } public void write(int aByte) { writer.write(aByte); } } }