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/* * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved. * 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; import java.io.BufferedReader; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.util.Enumeration; import java.util.Locale; import java.util.Map; /** * Provides a convenient implementation of the ServletRequest interface that * can be subclassed by developers wishing to adapt the request to a Servlet. * This class implements the Wrapper or Decorator pattern. Methods default to * calling through to the wrapped request object. * * @see javax.servlet.ServletRequest * * @since Servlet 2.3 */ public class ServletRequestWrapper implements ServletRequest { private ServletRequest request; /** * Creates a ServletRequest adaptor wrapping the given request object. * @throws java.lang.IllegalArgumentException if the request is null * * @param request the {@link ServletRequest} to be wrapped */ public ServletRequestWrapper(ServletRequest request) { if (request == null) { throw new IllegalArgumentException("Request cannot be null"); } this.request = request; } /** * Return the wrapped request object. * * @return the wrapped {@link ServletRequest} */ public ServletRequest getRequest() { return this.request; } /** * Sets the request object being wrapped. * * @param request the {@link ServletRequest} to be installed * * @throws java.lang.IllegalArgumentException if the request is null. * */ public void setRequest(ServletRequest request) { if (request == null) { throw new IllegalArgumentException("Request cannot be null"); } this.request = request; } /** * The default behavior of this method is to call getAttribute(String name) * on the wrapped request object. */ public Object getAttribute(String name) { return this.request.getAttribute(name); } /** * The default behavior of this method is to return getAttributeNames() * on the wrapped request object. */ public Enumeration<String> getAttributeNames() { return this.request.getAttributeNames(); } /** * The default behavior of this method is to return getCharacterEncoding() * on the wrapped request object. */ public String getCharacterEncoding() { return this.request.getCharacterEncoding(); } /** * The default behavior of this method is to set the character encoding * on the wrapped request object. */ public void setCharacterEncoding(String enc) throws UnsupportedEncodingException { this.request.setCharacterEncoding(enc); } /** * The default behavior of this method is to return getContentLength() * on the wrapped request object. */ public int getContentLength() { return this.request.getContentLength(); } /** * The default behavior of this method is to return getContentLengthLong() * on the wrapped request object. * * @since Servlet 3.1 */ public long getContentLengthLong() { return this.request.getContentLengthLong(); } /** * The default behavior of this method is to return getContentType() * on the wrapped request object. */ public String getContentType() { return this.request.getContentType(); } /** * The default behavior of this method is to return getInputStream() * on the wrapped request object. */ public ServletInputStream getInputStream() throws IOException { return this.request.getInputStream(); } /** * The default behavior of this method is to return * getParameter(String name) on the wrapped request object. */ public String getParameter(String name) { return this.request.getParameter(name); } /** * The default behavior of this method is to return getParameterMap() * on the wrapped request object. */ public Map<String, String[]> getParameterMap() { return this.request.getParameterMap(); } /** * The default behavior of this method is to return getParameterNames() * on the wrapped request object. */ public Enumeration<String> getParameterNames() { return this.request.getParameterNames(); } /** * The default behavior of this method is to return * getParameterValues(String name) on the wrapped request object. */ public String[] getParameterValues(String name) { return this.request.getParameterValues(name); } /** * The default behavior of this method is to return getProtocol() * on the wrapped request object. */ public String getProtocol() { return this.request.getProtocol(); } /** * The default behavior of this method is to return getScheme() * on the wrapped request object. */ public String getScheme() { return this.request.getScheme(); } /** * The default behavior of this method is to return getServerName() * on the wrapped request object. */ public String getServerName() { return this.request.getServerName(); } /** * The default behavior of this method is to return getServerPort() * on the wrapped request object. */ public int getServerPort() { return this.request.getServerPort(); } /** * The default behavior of this method is to return getReader() * on the wrapped request object. */ public BufferedReader getReader() throws IOException { return this.request.getReader(); } /** * The default behavior of this method is to return getRemoteAddr() * on the wrapped request object. */ public String getRemoteAddr() { return this.request.getRemoteAddr(); } /** * The default behavior of this method is to return getRemoteHost() * on the wrapped request object. */ public String getRemoteHost() { return this.request.getRemoteHost(); } /** * The default behavior of this method is to return * setAttribute(String name, Object o) on the wrapped request object. */ public void setAttribute(String name, Object o) { this.request.setAttribute(name, o); } /** * The default behavior of this method is to call * removeAttribute(String name) on the wrapped request object. */ public void removeAttribute(String name) { this.request.removeAttribute(name); } /** * The default behavior of this method is to return getLocale() * on the wrapped request object. */ public Locale getLocale() { return this.request.getLocale(); } /** * The default behavior of this method is to return getLocales() * on the wrapped request object. */ public Enumeration<Locale> getLocales() { return this.request.getLocales(); } /** * The default behavior of this method is to return isSecure() * on the wrapped request object. */ public boolean isSecure() { return this.request.isSecure(); } /** * The default behavior of this method is to return * getRequestDispatcher(String path) on the wrapped request object. */ public RequestDispatcher getRequestDispatcher(String path) { return this.request.getRequestDispatcher(path); } /** * The default behavior of this method is to return * getRealPath(String path) on the wrapped request object. * * @deprecated As of Version 2.1 of the Java Servlet API, * use {@link ServletContext#getRealPath} instead */ @Deprecated public String getRealPath(String path) { return this.request.getRealPath(path); } /** * The default behavior of this method is to return * getRemotePort() on the wrapped request object. * * @since Servlet 2.4 */ public int getRemotePort() { return this.request.getRemotePort(); } /** * The default behavior of this method is to return * getLocalName() on the wrapped request object. * * @since Servlet 2.4 */ public String getLocalName() { return this.request.getLocalName(); } /** * The default behavior of this method is to return * getLocalAddr() on the wrapped request object. * * @since Servlet 2.4 */ public String getLocalAddr() { return this.request.getLocalAddr(); } /** * The default behavior of this method is to return * getLocalPort() on the wrapped request object. * * @since Servlet 2.4 */ public int getLocalPort() { return this.request.getLocalPort(); } /** * Gets the servlet context to which the wrapped servlet request was last * dispatched. * * @return the servlet context to which the wrapped servlet request was * last dispatched * * @since Servlet 3.0 */ public ServletContext getServletContext() { return request.getServletContext(); } /** * The default behavior of this method is to invoke * {@link ServletRequest#startAsync} on the wrapped request object. * * @return the (re)initialized AsyncContext * * @throws IllegalStateException if the request is within the scope of * a filter or servlet that does not support asynchronous operations * (that is, {@link #isAsyncSupported} returns false), * or if this method is called again without any asynchronous dispatch * (resulting from one of the {@link AsyncContext#dispatch} methods), * is called outside the scope of any such dispatch, or is called again * within the scope of the same dispatch, or if the response has * already been closed * * @see ServletRequest#startAsync * * @since Servlet 3.0 */ public AsyncContext startAsync() throws IllegalStateException { return request.startAsync(); } /** * The default behavior of this method is to invoke * {@link ServletRequest#startAsync(ServletRequest, ServletResponse)} * on the wrapped request object. * * @param servletRequest the ServletRequest used to initialize the * AsyncContext * @param servletResponse the ServletResponse used to initialize the * AsyncContext * * @return the (re)initialized AsyncContext * * @throws IllegalStateException if the request is within the scope of * a filter or servlet that does not support asynchronous operations * (that is, {@link #isAsyncSupported} returns false), * or if this method is called again without any asynchronous dispatch * (resulting from one of the {@link AsyncContext#dispatch} methods), * is called outside the scope of any such dispatch, or is called again * within the scope of the same dispatch, or if the response has * already been closed * * @see ServletRequest#startAsync(ServletRequest, ServletResponse) * * @since Servlet 3.0 */ public AsyncContext startAsync(ServletRequest servletRequest, ServletResponse servletResponse) throws IllegalStateException { return request.startAsync(servletRequest, servletResponse); } /** * Checks if the wrapped request has been put into asynchronous mode. * * @return true if this request has been put into asynchronous mode, * false otherwise * * @see ServletRequest#isAsyncStarted * * @since Servlet 3.0 */ public boolean isAsyncStarted() { return request.isAsyncStarted(); } /** * Checks if the wrapped request supports asynchronous operation. * * @return true if this request supports asynchronous operation, false * otherwise * * @see ServletRequest#isAsyncSupported * * @since Servlet 3.0 */ public boolean isAsyncSupported() { return request.isAsyncSupported(); } /** * Gets the AsyncContext that was created or reinitialized by the * most recent invocation of {@link #startAsync} or * {@link #startAsync(ServletRequest,ServletResponse)} on the wrapped * request. * * @return the AsyncContext that was created or reinitialized by the * most recent invocation of {@link #startAsync} or * {@link #startAsync(ServletRequest,ServletResponse)} on * the wrapped request * * @throws IllegalStateException if this request has not been put * into asynchronous mode, i.e., if neither {@link #startAsync} nor * {@link #startAsync(ServletRequest,ServletResponse)} has been called * * @see ServletRequest#getAsyncContext * * @since Servlet 3.0 */ public AsyncContext getAsyncContext() { return request.getAsyncContext(); } /** * Checks (recursively) if this ServletRequestWrapper wraps the given * {@link ServletRequest} instance. * * @param wrapped the ServletRequest instance to search for * * @return true if this ServletRequestWrapper wraps the * given ServletRequest instance, false otherwise * * @since Servlet 3.0 */ public boolean isWrapperFor(ServletRequest wrapped) { if (request == wrapped) { return true; } else if (request instanceof ServletRequestWrapper) { return ((ServletRequestWrapper) request).isWrapperFor(wrapped); } else { return false; } } /** * Checks (recursively) if this ServletRequestWrapper wraps a * {@link ServletRequest} of the given class type. * * @param wrappedType the ServletRequest class type to * search for * * @return true if this ServletRequestWrapper wraps a * ServletRequest of the given class type, false otherwise * * @throws IllegalArgumentException if the given class does not * implement {@link ServletRequest} * * @since Servlet 3.0 */ public boolean isWrapperFor(Class<?> wrappedType) { if (!ServletRequest.class.isAssignableFrom(wrappedType)) { throw new IllegalArgumentException("Given class " + wrappedType.getName() + " not a subinterface of " + ServletRequest.class.getName()); } if (wrappedType.isAssignableFrom(request.getClass())) { return true; } else if (request instanceof ServletRequestWrapper) { return ((ServletRequestWrapper) request).isWrapperFor(wrappedType); } else { return false; } } /** * Gets the dispatcher type of the wrapped request. * * @return the dispatcher type of the wrapped request * * @see ServletRequest#getDispatcherType * * @since Servlet 3.0 */ public DispatcherType getDispatcherType() { return request.getDispatcherType(); } }