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The source code/* * Copyright 1999-2004 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 org.apache.jasper.runtime; import java.io.IOException; import java.util.Enumeration; import java.util.Hashtable; import java.util.NoSuchElementException; import java.util.Stack; import javax.servlet.Servlet; import javax.servlet.ServletConfig; import javax.servlet.ServletContext; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpSession; import javax.servlet.jsp.JspFactory; import javax.servlet.jsp.JspWriter; import javax.servlet.jsp.PageContext; import javax.servlet.jsp.tagext.BodyContent; /** * Implementation of the PageContext class from the JSP spec. * * @author Anil K. Vijendran * @author Larry Cable * @author Hans Bergsten */ public class PageContextImpl extends PageContext { PageContextImpl(JspFactory factory) { this.factory = factory; } /* static class InitAction implements java.security.PrivilegedAction { Servlet servlet; ServletRequest request; ServletResponse response; String errorPageURL; boolean needsSession; int bufferSize; boolean autoFlush; PageContextImpl pci; InitAction(PageContextImpl pci, Servlet s, ServletRequest req, ServletResponse res, String err, boolean n, int b, boolean a) { this.pci=pci; servlet=s; request=req; response=res; errorPageURL=err; needsSession=n; bufferSize=b; autoFlush=a; } public Object run() { try { pci._initialize(servlet, request, response, errorPageURL, needsSession, bufferSize, autoFlush); } catch( Throwable t ) { t. print Stack Trace(); } return null; } } */ public void initialize(Servlet servlet, ServletRequest request, ServletResponse response, String errorPageURL, boolean needsSession, int bufferSize, boolean autoFlush) throws IOException, IllegalStateException, IllegalArgumentException { // InitAction ia=new InitAction( this, servlet, request, response, // errorPageURL, needsSession, bufferSize, // autoFlush); // java.security.AccessController.doPrivileged( ia ); _initialize(servlet, request, response, errorPageURL, needsSession, bufferSize, autoFlush); } void _initialize(Servlet servlet, ServletRequest request, ServletResponse response, String errorPageURL, boolean needsSession, int bufferSize, boolean autoFlush) throws IOException, IllegalStateException, IllegalArgumentException { // initialize state this.servlet = servlet; this.config = servlet.getServletConfig(); this.context = config.getServletContext(); this.needsSession = needsSession; this.errorPageURL = errorPageURL; this.bufferSize = bufferSize; this.autoFlush = autoFlush; this.request = request; this.response = response; // setup session (if required) if (request instanceof HttpServletRequest && needsSession) this.session = ((HttpServletRequest)request).getSession(); if (needsSession && session == null) throw new IllegalStateException("Page needs a session and none is available"); // initialize the initial out ... // System.out.println("Initialize PageContextImpl " + out ); if( out == null ) { out = _createOut(bufferSize, autoFlush); // throws } else ((JspWriterImpl)out).init(response, bufferSize, autoFlush ); if (this.out == null) throw new IllegalStateException("failed initialize JspWriter"); // register names/values as per spec setAttribute(OUT, this.out); setAttribute(REQUEST, request); setAttribute(RESPONSE, response); if (session != null) setAttribute(SESSION, session); setAttribute(PAGE, servlet); setAttribute(CONFIG, config); setAttribute(PAGECONTEXT, this); setAttribute(APPLICATION, context); } public void release() { servlet = null; config = null; context = null; needsSession = false; errorPageURL = null; bufferSize = JspWriter.DEFAULT_BUFFER; autoFlush = true; request = null; response = null; // Reuse // XXX problems - need to fix them first!! out = null; // out is closed elsewhere if( out instanceof JspWriterImpl ) ((JspWriterImpl)out).recycle(); session = null; attributes.clear(); } public Object getAttribute(String name) { return attributes.get(name); } public Object getAttribute(String name, int scope) { switch (scope) { case PAGE_SCOPE: return attributes.get(name); case REQUEST_SCOPE: return request.getAttribute(name); case SESSION_SCOPE: if (session == null) throw new IllegalArgumentException("can't access SESSION_SCOPE without an HttpSession"); else return session.getAttribute(name); case APPLICATION_SCOPE: return context.getAttribute(name); default: throw new IllegalArgumentException("unidentified scope"); } } public void setAttribute(String name, Object attribute) { attributes.put(name, attribute); } public void setAttribute(String name, Object o, int scope) { switch (scope) { case PAGE_SCOPE: attributes.put(name, o); break; case REQUEST_SCOPE: request.setAttribute(name, o); break; case SESSION_SCOPE: if (session == null) throw new IllegalArgumentException("can't access SESSION_SCOPE without an HttpSession"); else session.setAttribute(name, o); break; case APPLICATION_SCOPE: context.setAttribute(name, o); break; default: throw new IllegalArgumentException( "Invalid scope " + scope ); } } public void removeAttribute(String name, int scope) { switch (scope) { case PAGE_SCOPE: attributes.remove(name); break; case REQUEST_SCOPE: request.removeAttribute(name); case SESSION_SCOPE: if (session == null) throw new IllegalArgumentException("can't access SESSION_SCOPE without an HttpSession"); else session.removeAttribute(name); // was: // session.removeValue(name); // REVISIT Verify this is correct - akv break; case APPLICATION_SCOPE: context.removeAttribute(name); break; default: throw new IllegalArgumentException( "Invalid scope " + scope ); } } public int getAttributesScope(String name) { if (attributes.get(name) != null) return PAGE_SCOPE; if (request.getAttribute(name) != null) return REQUEST_SCOPE; if (session != null) { if (session.getAttribute(name) != null) return SESSION_SCOPE; } if (context.getAttribute(name) != null) return APPLICATION_SCOPE; return 0; } public Object findAttribute(String name) { Object o = attributes.get(name); if (o != null) return o; o = request.getAttribute(name); if (o != null) return o; if (session != null) { o = session.getAttribute(name); if (o != null) return o; } return context.getAttribute(name); } public Enumeration getAttributeNamesInScope(int scope) { switch (scope) { case PAGE_SCOPE: return attributes.keys(); case REQUEST_SCOPE: return request.getAttributeNames(); case SESSION_SCOPE: if (session != null) { return session.getAttributeNames(); } else throw new IllegalArgumentException("can't access SESSION_SCOPE without an HttpSession"); case APPLICATION_SCOPE: return context.getAttributeNames(); default: return new Enumeration() { // empty enumeration public boolean hasMoreElements() { return false; } public Object nextElement() { throw new NoSuchElementException(); } }; } } public void removeAttribute(String name) { try { removeAttribute(name, PAGE_SCOPE); removeAttribute(name, REQUEST_SCOPE); if( session != null ) { removeAttribute(name, SESSION_SCOPE); } removeAttribute(name, APPLICATION_SCOPE); } catch (Exception ex) { // we remove as much as we can, and // simply ignore possible exceptions } } public JspWriter getOut() { return out; } public HttpSession getSession() { return session; } public Servlet getServlet() { return servlet; } public ServletConfig getServletConfig() { return config; } public ServletContext getServletContext() { return config.getServletContext(); } public ServletRequest getRequest() { return request; } public ServletResponse getResponse() { return response; } public Exception getException() { return (Exception)request.getAttribute(EXCEPTION); } public Object getPage() { return servlet; } private final String getAbsolutePathRelativeToContext(String relativeUrlPath) { String path = relativeUrlPath; if (!path.startsWith("/")) { String uri = (String) request.getAttribute("javax.servlet.include.servlet_path"); if (uri == null) uri = ((HttpServletRequest) request).getServletPath(); String baseURI = uri.substring(0, uri.lastIndexOf('/')); path = baseURI+'/'+path; } return path; } public void include(String relativeUrlPath) throws ServletException, IOException { String path = getAbsolutePathRelativeToContext(relativeUrlPath); out.flush(); context.getRequestDispatcher(path).include(request, response); } public void forward(String relativeUrlPath) throws ServletException, IOException { String path = getAbsolutePathRelativeToContext(relativeUrlPath); if( out!=null ) { out.clearBuffer(); } context.getRequestDispatcher(path).forward(request, response); } Stack writerStack = new Stack(); public BodyContent pushBody() { JspWriter previous = out; writerStack.push(out); out = new BodyContentImpl(previous); return (BodyContent) out; } public JspWriter popBody() { out = (JspWriter) writerStack.pop(); return out; } public void handlePageException(Exception e) throws IOException, ServletException { // set the request attribute with the exception. request.setAttribute("javax.servlet.jsp.jspException", e); if (errorPageURL != null && !errorPageURL.equals("")) { try { forward(errorPageURL); } catch (IllegalStateException ise) { include(errorPageURL); } } // Otherwise throw the exception wrapped inside a ServletException. else { // Set the exception as the root cause in the ServletException // to get a stack trace for the real problem if( e instanceof IOException ) throw (IOException)e; if( e instanceof ServletException ) throw (ServletException) e; throw new ServletException(e); } } protected JspWriter _createOut(int bufferSize, boolean autoFlush) throws IOException, IllegalArgumentException { // This may fail for security expcetions, if the sandbox is broken !! // try { return new JspWriterImpl(response, bufferSize, autoFlush); // } catch( Throwable t ) { // loghelper.log("creating out", t); // return null; // } } /* * fields */ // per Servlet state protected Servlet servlet; protected ServletConfig config; protected ServletContext context; protected JspFactory factory; protected boolean needsSession; protected String errorPageURL; protected boolean autoFlush; protected int bufferSize; // page scope attributes protected transient Hashtable attributes = new Hashtable(16); // per request state protected transient ServletRequest request; protected transient ServletResponse response; protected transient Object page; protected transient HttpSession session; // initial output stream protected transient JspWriter out; 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