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/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved. * * The contents of this file are subject to the terms of either the GNU * General Public License Version 2 only ("GPL") or the Common Development * and Distribution License("CDDL") (collectively, the "License"). You * may not use this file except in compliance with the License. You can * obtain a copy of the License at * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html * or packager/legal/LICENSE.txt. See the License for the specific * language governing permissions and limitations under the License. * * When distributing the software, include this License Header Notice in each * file and include the License file at packager/legal/LICENSE.txt. * * GPL Classpath Exception: * Oracle designates this particular file as subject to the "Classpath" * exception as provided by Oracle in the GPL Version 2 section of the License * file that accompanied this code. * * Modifications: * If applicable, add the following below the License Header, with the fields * enclosed by brackets [] replaced by your own identifying information: * "Portions Copyright [year] [name of copyright owner]" * * Contributor(s): * If you wish your version of this file to be governed by only the CDDL or * only the GPL Version 2, indicate your decision by adding "[Contributor] * elects to include this software in this distribution under the [CDDL or GPL * Version 2] license." If you don't indicate a single choice of license, a * recipient has the option to distribute your version of this file under * either the CDDL, the GPL Version 2 or to extend the choice of license to * its licensees as provided above. However, if you add GPL Version 2 code * and therefore, elected the GPL Version 2 license, then the option applies * only if the new code is made subject to such option by the copyright * holder. * * * This file incorporates work covered by the following copyright and * permission notice: * * Copyright 2004 The Apache Software Foundation * * Licensed 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 javax.servlet.jsp.el; import java.beans.FeatureDescriptor; import java.util.Iterator; import java.util.ArrayList; import java.util.Collection; import java.util.Enumeration; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.Set; import javax.servlet.ServletContext; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServletRequest; import javax.servlet.jsp.PageContext; import javax.servlet.jsp.JspContext; import javax.el.PropertyNotWritableException; import javax.el.ELContext; import javax.el.ELResolver; /** * Defines variable resolution behavior for the EL implicit objects * defined in the JSP specification. * * <p>The following variables are resolved by this <code>ELResolver</code>, * as per the JSP specification: * <ul> * <li><code>pageContext</code> - the <code>PageContext</code> object.</li> * <li><code>pageScope</code> - a <code>Map</code> that maps page-scoped * attribute names to their values.</li> * <li><code>requestScope</code> - a <code>Map</code> that maps * request-scoped attribute names to their values.</li> * <li><code>sessionScope</code> - a <code>Map</code> that maps * session-scoped attribute names to their values.</li> * <li><code>applicationScope</code> - a <code>Map</code> that maps * application-scoped attribute names to their values.</li> * <li><code>param</code> - a <code>Map</code> that maps parameter * names to a single String parameter value (obtained by calling * <code>ServletRequest.getParameter(String name)).</li> * <li><code>paramValues</code> - a <code>Map</code> that maps parameter * names to a <code>String[]</code> of all values for that * parameter (obtained by calling * <code>ServletRequest.getParameterValues(String name))</code>.</li> * <li><code>header</code> - a <code>Map</code> that maps header names * to a single String header value (obtained by calling * <code>HttpServletRequest.getHeader(String name))</code>.</li> * <li><code>headerValues</code> - a <code>Map</code> that maps header * names to a <code>String[]</code> of all values for that header * (obtained by calling * <code>HttpServletRequest.getHeaders(String))</code>.</li> * <li><code>cookie</code> - a <code>Map</code> that maps cookie names * to a single <code>Cookie</code> object. Cookies are retrieved * according to the semantics of * <code>HttpServletRequest.getCookies()</code>. If the same name * is shared by multiple cookies, an implementation must use the * first one encountered in the array of <code>Cookie</code> objects * returned by the <code>getCookies()</code> method. However, users * of the cookie implicit object must be aware that the ordering * of cookies is currently unspecified in the servlet * specification.</li> * <li><code>initParam</code> - a <code>Map</code> that maps context * initialization parameter names to their String parameter * value (obtained by calling * <code>ServletContext.getInitParameter(String name))</code>.</li> * </ul></p> * * @see javax.el.ELResolver * @since JSP 2.1 */ public class ImplicitObjectELResolver extends ELResolver { /** * If the base object is <code>null</code>, and the property matches * the name of a JSP implicit object, returns the implicit object. * * <p>The <code>propertyResolved</code> property of the * <code>ELContext</code> object must be set to <code>true</code> by * this resolver before returning if an implicit object is matched. If * this property is not <code>true</code> after this method is called, * the caller should ignore the return value.</p> * * @param context The context of this evaluation. * @param base Only <code>null</code> is handled by this resolver. * Other values will result in an immediate return. * @param property The name of the implicit object to resolve. * @return If the <code>propertyResolved</code> property of * <code>ELContext</code> was set to <code>true</code>, then * the implicit object; otherwise undefined. * @throws NullPointerException if context is <code>null</code> * @throws ELException if an exception was thrown while performing * the property or variable resolution. The thrown exception * must be included as the cause property of this exception, if * available. */ public Object getValue(ELContext context, Object base, Object property) { if (context == null) { throw new NullPointerException(); } if (base != null) { return null; } PageContext ctxt = (PageContext) context.getContext(JspContext.class); if ("pageContext".equals(property)) { context.setPropertyResolved(true); return ctxt; } ImplicitObjects implicitObjects = ImplicitObjects.getImplicitObjects(ctxt); if ("pageScope".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getPageScopeMap(); } if ("requestScope".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getRequestScopeMap(); } if ("sessionScope".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getSessionScopeMap(); } if ("applicationScope".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getApplicationScopeMap(); } if ("param".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getParamMap(); } if ("paramValues".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getParamsMap(); } if ("header".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getHeaderMap(); } if ("headerValues".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getHeadersMap(); } if ("initParam".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getInitParamMap(); } if ("cookie".equals(property)) { context.setPropertyResolved(true); return implicitObjects.getCookieMap(); } return null; } /** * If the base object is <code>null</code>, and the property matches * the name of a JSP implicit object, returns <code>null</code> to * indicate that no types are ever accepted to <code>setValue()</code>. * * <p>The <code>propertyResolved</code> property of the * <code>ELContext</code> object must be set to <code>true</code> by * this resolver before returning if an implicit object is matched. If * this property is not <code>true</code> after this method is called, * the caller should ignore the return value.</p> * * @param context The context of this evaluation. * @param base Only <code>null</code> is handled by this resolver. * Other values will result in an immediate return. * @param property The name of the implicit object to resolve. * @return If the <code>propertyResolved</code> property of * <code>ELContext</code> was set to <code>true</code>, then * <code>null</code>; otherwise undefined. * @throws NullPointerException if context is <code>null</code> * @throws ELException if an exception was thrown while performing * the property or variable resolution. The thrown exception * must be included as the cause property of this exception, if * available. */ public Class getType(ELContext context, Object base, Object property) { if (context == null) { throw new NullPointerException(); } if ((base == null) && ("pageContext".equals(property) || "pageScope".equals(property)) || "requestScope".equals(property) || "sessionScope".equals(property) || "applicationScope".equals(property) || "param".equals(property) || "paramValues".equals(property) || "header".equals(property) || "headerValues".equals(property) || "initParam".equals(property) || "cookie".equals(property)) { context.setPropertyResolved(true); } return null; } /** * If the base object is <code>null</code>, and the property matches * the name of a JSP implicit object, throws * <code>PropertyNotWritableException</code> to indicate that implicit * objects cannot be overwritten. * * <p>The <code>propertyResolved</code> property of the * <code>ELContext</code> object must be set to <code>true</code> by * this resolver before returning if an implicit object is matched. If * this property is not <code>true</code> after this method is called, * the caller should ignore the return value.</p> * * @param context The context of this evaluation. * @param base Only <code>null</code> is handled by this resolver. * Other values will result in an immediate return. * @param property The name of the implicit object. * @param val The value to be associated with the implicit object. * @throws NullPointerException if context is <code>null</code>. * @throws PropertyNotWritableException always thrown, if the * implicit object name is recognized by this resolver. * @throws ELException if an exception was thrown while performing * the property or variable resolution. The thrown exception * must be included as the cause property of this exception, if * available. */ public void setValue(ELContext context, Object base, Object property, Object val) { if (context == null) { throw new NullPointerException(); } if ((base == null) && ("pageContext".equals(property) || "pageScope".equals(property)) || "requestScope".equals(property) || "sessionScope".equals(property) || "applicationScope".equals(property) || "param".equals(property) || "paramValues".equals(property) || "header".equals(property) || "headerValues".equals(property) || "initParam".equals(property) || "cookie".equals(property)) { throw new PropertyNotWritableException(); } } /** * If the base object is <code>null</code>, and the property matches * the name of a JSP implicit object, returns <code>true</code> * to indicate that implicit objects cannot be overwritten. * * <p>The <code>propertyResolved</code> property of the * <code>ELContext</code> object must be set to <code>true</code> by * this resolver before returning if an implicit object is matched. If * this property is not <code>true</code> after this method is called, * the caller should ignore the return value.</p> * * @param context The context of this evaluation. * @param base Only <code>null</code> is handled by this resolver. * Other values will result in an immediate return. * @param property The name of the implicit object. * @return If the <code>propertyResolved</code> property of * <code>ELContext</code> was set to <code>true</code>, then * <code>true</code>; otherwise undefined. * @throws NullPointerException if context is <code>null</code>. * @throws ELException if an exception was thrown while performing * the property or variable resolution. The thrown exception * must be included as the cause property of this exception, if * available. */ public boolean isReadOnly(ELContext context, Object base, Object property) { if (context == null) { throw new NullPointerException(); } if ((base == null) && ("pageContext".equals(property) || "pageScope".equals(property)) || "requestScope".equals(property) || "sessionScope".equals(property) || "applicationScope".equals(property) || "param".equals(property) || "paramValues".equals(property) || "header".equals(property) || "headerValues".equals(property) || "initParam".equals(property) || "cookie".equals(property)) { context.setPropertyResolved(true); return true; } return false; // Doesn't matter } /** * If the base object is <code>null</code>, and the property matches * the name of a JSP implicit object, returns an <code>Iterator</code> * containing <code>FeatureDescriptor</code> objects with information * about each JSP implicit object resolved by this resolver. Otherwise, * returns <code>null</code>. * * <p>The <code>Iterator</code> returned must contain one instance of * {@link java.beans.FeatureDescriptor} for each of the EL implicit objects * defined by the JSP spec. Each info object contains information about * a single implicit object, and is initialized as follows: * <dl> * <li>displayName - The name of the implicit object.</li> * <li>name - Same as displayName property.</li> * <li>shortDescription - A suitable description for the implicit * object. Will vary by implementation.</li> * <li>expert - <code>false</code></li> * <li>hidden - <code>false</code></li> * <li>preferred - <code>true</code></li> * </dl> * In addition, the following named attributes must be set in the * returned <code>FeatureDescriptor</code>s: * <dl> * <li>{@link ELResolver#TYPE} - The runtime type of the implicit object.</li> * <li>{@link ELResolver#RESOLVABLE_AT_DESIGN_TIME} - <code>true</code>.</li> * </dl></p> * * @param context The context of this evaluation. * @param base Only <code>null</code> is handled by this resolver. * Other values will result in a <code>null</code> return value. * @return An <code>Iterator</code> containing one * <code>FeatureDescriptor</code> object for each implicit object, or * <code>null</code> if <code>base</code> is not <code>null</code>. */ public Iterator<FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base) { ArrayList<FeatureDescriptor> list = new ArrayList<FeatureDescriptor>(11); // pageContext FeatureDescriptor descriptor = new FeatureDescriptor(); descriptor.setName("pageContext"); descriptor.setDisplayName("pageContext"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", javax.servlet.jsp.PageContext.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // pageScope descriptor = new FeatureDescriptor(); descriptor.setName("pageScope"); descriptor.setDisplayName("pageScope"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // requestScope descriptor = new FeatureDescriptor(); descriptor.setName("requestScope"); descriptor.setDisplayName("requestScope"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // sessionScope descriptor = new FeatureDescriptor(); descriptor.setName("sessionScope"); descriptor.setDisplayName("sessionScope"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // applicationScope descriptor = new FeatureDescriptor(); descriptor.setName("applicationScope"); descriptor.setDisplayName("applicationScope"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // param descriptor = new FeatureDescriptor(); descriptor.setName("param"); descriptor.setDisplayName("param"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // paramValues descriptor = new FeatureDescriptor(); descriptor.setName("paramValues"); descriptor.setDisplayName("paramValues"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // header descriptor = new FeatureDescriptor(); descriptor.setName("header"); descriptor.setDisplayName("header"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // headerValues descriptor = new FeatureDescriptor(); descriptor.setName("headerValues"); descriptor.setDisplayName("headerValues"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // cookie descriptor = new FeatureDescriptor(); descriptor.setName("cookie"); descriptor.setDisplayName("cookie"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); // initParam descriptor = new FeatureDescriptor(); descriptor.setName("initParam"); descriptor.setDisplayName("initParam"); //descriptor.setShortDescription(""); descriptor.setExpert(false); descriptor.setHidden(false); descriptor.setPreferred(true); descriptor.setValue("type", Map.class); descriptor.setValue("resolvableAtDesignTime", Boolean.TRUE); list.add(descriptor); return list.iterator(); } /** * If the base object is <code>null</code>, returns * <code>String.class</code>. Otherwise, returns <code>null</code>. * * @param context The context of this evaluation. * @param base Only <code>null</code> is handled by this resolver. * Other values will result in a <code>null</code> return value. * @return <code>null</code> if base is not <code>null</code>; otherwise * <code>String.class</code>. */ public Class<String> getCommonPropertyType(ELContext context, Object base) { if (base == null) { return String.class; } return null; } // XXX - I moved this class from commons-el to an inner class here // so that we do not have a dependency from the JSP APIs into commons-el. // There might be a better way to do this. /** * <p>This class is used to generate the implicit Map and List objects * that wrap various elements of the PageContext. It also returns the * correct implicit object for a given implicit object name. * * @author Nathan Abramson - Art Technology Group **/ private static class ImplicitObjects { //------------------------------------- // Constants //------------------------------------- // XXX - This probably needs to change, now that this is in a // standard pkg. static final String sAttributeName = "org.apache.taglibs.standard.ImplicitObjects"; //------------------------------------- // Member variables //------------------------------------- PageContext mContext; Map<String, Object> mPage; Map<String, Object> mRequest; Map<String, Object> mSession; Map<String, Object> mApplication; Map<String, String> mParam; Map<String, String[]> mParams; Map<String, String> mHeader; Map<String, String[]> mHeaders; Map<String, String> mInitParam; Map<String, Cookie> mCookie; //------------------------------------- /** * * Constructor **/ public ImplicitObjects(PageContext pContext) { mContext = pContext; } //------------------------------------- /** * * Finds the ImplicitObjects associated with the PageContext, * creating it if it doesn't yet exist. **/ public static ImplicitObjects getImplicitObjects(PageContext pContext) { ImplicitObjects objs = (ImplicitObjects) pContext.getAttribute(sAttributeName, PageContext.PAGE_SCOPE); if (objs == null) { objs = new ImplicitObjects(pContext); pContext.setAttribute(sAttributeName, objs, PageContext.PAGE_SCOPE); } return objs; } //------------------------------------- /** * * Returns the Map that "wraps" page-scoped attributes **/ public Map<String, Object> getPageScopeMap() { if (mPage == null) { mPage = createPageScopeMap(mContext); } return mPage; } //------------------------------------- /** * * Returns the Map that "wraps" request-scoped attributes **/ public Map<String, Object> getRequestScopeMap() { if (mRequest == null) { mRequest = createRequestScopeMap(mContext); } return mRequest; } //------------------------------------- /** * * Returns the Map that "wraps" session-scoped attributes **/ public Map<String, Object> getSessionScopeMap() { if (mSession == null) { mSession = createSessionScopeMap(mContext); } return mSession; } //------------------------------------- /** * * Returns the Map that "wraps" application-scoped attributes **/ public Map<String, Object> getApplicationScopeMap() { if (mApplication == null) { mApplication = createApplicationScopeMap(mContext); } return mApplication; } //------------------------------------- /** * * Returns the Map that maps parameter name to a single parameter * values. **/ public Map<String, String> getParamMap() { if (mParam == null) { mParam = createParamMap(mContext); } return mParam; } //------------------------------------- /** * * Returns the Map that maps parameter name to an array of parameter * values. **/ public Map<String, String[]> getParamsMap() { if (mParams == null) { mParams = createParamsMap(mContext); } return mParams; } //------------------------------------- /** * * Returns the Map that maps header name to a single header * values. **/ public Map<String, String> getHeaderMap() { if (mHeader == null) { mHeader = createHeaderMap(mContext); } return mHeader; } //------------------------------------- /** * * Returns the Map that maps header name to an array of header * values. **/ public Map<String, String[]> getHeadersMap() { if (mHeaders == null) { mHeaders = createHeadersMap(mContext); } return mHeaders; } //------------------------------------- /** * * Returns the Map that maps init parameter name to a single init * parameter values. **/ public Map<String, String> getInitParamMap() { if (mInitParam == null) { mInitParam = createInitParamMap(mContext); } return mInitParam; } //------------------------------------- /** * * Returns the Map that maps cookie name to the first matching * Cookie in request.getCookies(). **/ public Map<String, Cookie> getCookieMap() { if (mCookie == null) { mCookie = createCookieMap(mContext); } return mCookie; } //------------------------------------- // Methods for generating wrapper maps //------------------------------------- /** * * Creates the Map that "wraps" page-scoped attributes **/ public static Map<String, Object> createPageScopeMap(PageContext pContext) { final PageContext context = pContext; return new EnumeratedMap<String, Object>() { public Enumeration<String> enumerateKeys() { return context.getAttributeNamesInScope(PageContext.PAGE_SCOPE); } public Object getValue(Object pKey) { if (pKey instanceof String) { return context.getAttribute((String) pKey, PageContext.PAGE_SCOPE); } else { return null; } } public boolean isMutable() { return true; } }; } //------------------------------------- /** * * Creates the Map that "wraps" request-scoped attributes **/ public static Map<String, Object> createRequestScopeMap(PageContext pContext) { final PageContext context = pContext; return new EnumeratedMap<String, Object>() { public Enumeration<String> enumerateKeys() { return context.getAttributeNamesInScope(PageContext.REQUEST_SCOPE); } public Object getValue(Object pKey) { if (pKey instanceof String) { return context.getAttribute((String) pKey, PageContext.REQUEST_SCOPE); } else { return null; } } public boolean isMutable() { return true; } }; } //------------------------------------- /** * * Creates the Map that "wraps" session-scoped attributes **/ public static Map<String, Object> createSessionScopeMap(PageContext pContext) { final PageContext context = pContext; return new EnumeratedMap<String, Object>() { public Enumeration<String> enumerateKeys() { return context.getAttributeNamesInScope(PageContext.SESSION_SCOPE); } public Object getValue(Object pKey) { if (pKey instanceof String) { return context.getAttribute((String) pKey, PageContext.SESSION_SCOPE); } else { return null; } } public boolean isMutable() { return true; } }; } //------------------------------------- /** * * Creates the Map that "wraps" application-scoped attributes **/ public static Map<String, Object> createApplicationScopeMap(PageContext pContext) { final PageContext context = pContext; return new EnumeratedMap<String, Object>() { public Enumeration<String> enumerateKeys() { return context.getAttributeNamesInScope(PageContext.APPLICATION_SCOPE); } public Object getValue(Object pKey) { if (pKey instanceof String) { return context.getAttribute((String) pKey, PageContext.APPLICATION_SCOPE); } else { return null; } } public boolean isMutable() { return true; } }; } //------------------------------------- /** * * Creates the Map that maps parameter name to single parameter * value. **/ public static Map<String, String> createParamMap(PageContext pContext) { final HttpServletRequest request = (HttpServletRequest) pContext.getRequest(); return new EnumeratedMap<String, String>() { public Enumeration<String> enumerateKeys() { return request.getParameterNames(); } public String getValue(Object pKey) { if (pKey instanceof String) { return request.getParameter((String) pKey); } else { return null; } } public boolean isMutable() { return false; } }; } //------------------------------------- /** * * Creates the Map that maps parameter name to an array of parameter * values. **/ public static Map<String, String[]> createParamsMap(PageContext pContext) { final HttpServletRequest request = (HttpServletRequest) pContext.getRequest(); return new EnumeratedMap<String, String[]>() { public Enumeration<String> enumerateKeys() { return request.getParameterNames(); } public String[] getValue(Object pKey) { if (pKey instanceof String) { return request.getParameterValues((String) pKey); } else { return null; } } public boolean isMutable() { return false; } }; } //------------------------------------- /** * * Creates the Map that maps header name to single header * value. **/ public static Map<String, String> createHeaderMap(PageContext pContext) { final HttpServletRequest request = (HttpServletRequest) pContext.getRequest(); return new EnumeratedMap<String, String>() { public Enumeration<String> enumerateKeys() { return request.getHeaderNames(); } public String getValue(Object pKey) { if (pKey instanceof String) { return request.getHeader((String) pKey); } else { return null; } } public boolean isMutable() { return false; } }; } //------------------------------------- /** * * Creates the Map that maps header name to an array of header * values. **/ public static Map<String, String[]> createHeadersMap(PageContext pContext) { final HttpServletRequest request = (HttpServletRequest) pContext.getRequest(); return new EnumeratedMap<String, String[]>() { public Enumeration<String> enumerateKeys() { return request.getHeaderNames(); } public String[] getValue(Object pKey) { if (pKey instanceof String) { // Drain the header enumeration List<String> l = new ArrayList<String>(); Enumeration<String> e = request.getHeaders((String) pKey); if (e != null) { while (e.hasMoreElements()) { l.add(e.nextElement()); } } return l.toArray(new String[l.size()]); } else { return null; } } public boolean isMutable() { return false; } }; } //------------------------------------- /** * * Creates the Map that maps init parameter name to single init * parameter value. **/ public static Map<String, String> createInitParamMap(PageContext pContext) { final ServletContext context = pContext.getServletContext(); return new EnumeratedMap<String, String>() { public Enumeration<String> enumerateKeys() { return context.getInitParameterNames(); } public String getValue(Object pKey) { if (pKey instanceof String) { return context.getInitParameter((String) pKey); } else { return null; } } public boolean isMutable() { return false; } }; } //------------------------------------- /** * * Creates the Map that maps cookie name to the first matching * Cookie in request.getCookies(). **/ public static Map<String, Cookie> createCookieMap(PageContext pContext) { // Read all the cookies and construct the entire map HttpServletRequest request = (HttpServletRequest) pContext.getRequest(); Cookie[] cookies = request.getCookies(); Map<String, Cookie> ret = new HashMap<String, Cookie>(); for (int i = 0; cookies != null && i < cookies.length; i++) { Cookie cookie = cookies[i]; if (cookie != null) { String name = cookie.getName(); if (!ret.containsKey(name)) { ret.put(name, cookie); } } } return ret; } //------------------------------------- } // XXX - I moved this class from commons-el to an inner class here // so that we do not have a dependency from the JSP APIs into commons-el. // There might be a better way to do this. /** * <p>This is a Map implementation driven by a data source that only * provides an enumeration of keys and a getValue(key) method. This * class must be subclassed to implement those methods. * * <p>Some of the methods may incur a performance penalty that * involves enumerating the entire data source. In these cases, the * Map will try to save the results of that enumeration, but only if * the underlying data source is immutable. * * @author Nathan Abramson - Art Technology Group **/ private static abstract class EnumeratedMap<K, V> implements Map<K, V> { //------------------------------------- // Member variables //------------------------------------- Map<K, V> mMap; //------------------------------------- public void clear() { throw new UnsupportedOperationException(); } //------------------------------------- public boolean containsKey(Object pKey) { return getValue(pKey) != null; } //------------------------------------- public boolean containsValue(Object pValue) { return getAsMap().containsValue(pValue); } //------------------------------------- public Set<Map.Entry<K, V>> entrySet() { return getAsMap().entrySet(); } //------------------------------------- public V get(Object pKey) { return getValue(pKey); } //------------------------------------- public boolean isEmpty() { return !enumerateKeys().hasMoreElements(); } //------------------------------------- public Set<K> keySet() { return getAsMap().keySet(); } //------------------------------------- public V put(K pKey, V pValue) { throw new UnsupportedOperationException(); } //------------------------------------- public void putAll(Map<? extends K, ? extends V> pMap) { throw new UnsupportedOperationException(); } //------------------------------------- public V remove(Object pKey) { throw new UnsupportedOperationException(); } //------------------------------------- public int size() { return getAsMap().size(); } //------------------------------------- public Collection<V> values() { return getAsMap().values(); } //------------------------------------- // Abstract methods //------------------------------------- /** * * Returns an enumeration of the keys **/ public abstract Enumeration<K> enumerateKeys(); //------------------------------------- /** * * Returns true if it is possible for this data source to change **/ public abstract boolean isMutable(); //------------------------------------- /** * * Returns the value associated with the given key, or null if not * found. **/ public abstract V getValue(Object pKey); //------------------------------------- /** * * Converts the MapSource to a Map. If the map is not mutable, this * is cached **/ public Map<K, V> getAsMap() { if (mMap != null) { return mMap; } else { Map<K, V> m = convertToMap(); if (!isMutable()) { mMap = m; } return m; } } //------------------------------------- /** * * Converts to a Map **/ Map<K, V> convertToMap() { Map<K, V> ret = new HashMap<K, V>(); for (Enumeration<K> e = enumerateKeys(); e.hasMoreElements();) { K key = e.nextElement(); V value = getValue(key); ret.put(key, value); } return ret; } //------------------------------------- } }