/*
* The Apache Software License, Version 1.1
*
* Copyright (c) 1999 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution, if
* any, must include the following acknowlegement:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "The Jakarta Project", "Tomcat", and "Apache Software
* Foundation" must not be used to endorse or promote products derived
* from this software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache"
* nor may "Apache" appear in their names without prior written
* permission of the Apache Group.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.jasper.servlet;
import javax.servlet.Servlet;
import javax.servlet.ServletContext;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.SingleThreadModel;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.jsp.HttpJspPage;
import javax.servlet.jsp.JspFactory;
import java.util.Hashtable;
import java.util.Enumeration;
import java.io.File;
import java.io.PrintWriter;
import java.io.IOException;
import java.io.FileNotFoundException;
import org.apache.jasper.JasperException;
import org.apache.jasper.Constants;
import org.apache.jasper.Options;
import org.apache.jasper.EmbededServletOptions;
import org.apache.jasper.JspCompilationContext;
import org.apache.jasper.JspEngineContext;
import org.apache.jasper.compiler.Mangler;
import org.apache.jasper.runtime.*;
import org.apache.jasper.compiler.Compiler;
import org.apache.tomcat.logging.Logger;
/**
* The JSP engine (a.k.a Jasper)!
*
* @author Anil K. Vijendran
* @author Harish Prabandham
* @author Marc A. Saegesser
*/
public class JspServlet extends HttpServlet {
/**
* Adds reference counting to the JSP implementation servlet. This
* is required to handle the case where a JSP implementation servlet
* is executing requests on several threads when a new implementation
* arrives (the JSP source was updated). We need to wait until all
* the requests complete before calling the implementation servlet's
* destroy() method.
*/
class JspCountedServlet extends HttpServlet
{
private Servlet servlet = null;
private int threadCount = 0;
private boolean destroyed = false;
public JspCountedServlet(Servlet servlet)
{
this.servlet = servlet;
}
public void init(ServletConfig config) throws ServletException, JasperException
{
try{
servlet.init(config);
}catch(NullPointerException e){
throw new JasperException(e);
}
}
public void service(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException, JasperException
{
try{
incrementCount();
servlet.service(req, res);
}catch(NullPointerException e){
throw new JasperException(e);
}finally{
decrementCount();
}
}
/*
* Flags this servlet for destrction once all active requests have completed.
* After calling this method it is invalid to call service().
*/
public void destroy()
{
destroyed = true;
if(getCount() == 0)
doDestroy();
}
private void doDestroy()
{
try{
servlet.destroy();
servlet = null;
}catch(NullPointerException e){
}
}
private synchronized void incrementCount()
{
threadCount++;
}
private synchronized void decrementCount()
{
if(threadCount <= 0){
Constants.message("jsp.error.badcount", Logger.ERROR);
return;
}
--threadCount;
if(threadCount == 0 && destroyed)
doDestroy();
}
private synchronized int getCount()
{
return threadCount;
}
}
class JspServletWrapper {
JspCountedServlet theServlet;
String jspUri;
boolean isErrorPage;
Class servletClass;
JspServletWrapper(String jspUri, boolean isErrorPage) {
this.jspUri = jspUri;
this.isErrorPage = isErrorPage;
this.theServlet = null;
}
public synchronized void instantiateServlet(Class servletClass) throws JasperException, ServletException
{
try {
this.servletClass = servletClass;
// If we're replacing an existing JSP Implementation class, then
// schedule it for destruction
if(theServlet != null)
theServlet.destroy();
// Create an instance of the JSP implementation class
Servlet servlet = (Servlet) servletClass.newInstance();
// Set the class loader
if(servlet instanceof HttpJspBase) {
((HttpJspBase)servlet).setClassLoader(JspServlet.this.parentClassLoader);
}
// Wrap this servlet in a counted servlet
theServlet = new JspCountedServlet(servlet);
// Call the JSP Implementation servlet's init() method. This
// will cause the page's jspInit() method to be invoked if one exists.
theServlet.init(JspServlet.this.config);
} catch(Exception ex) {
throw new JasperException(ex);
}
}
public synchronized Servlet getServlet()
{
return theServlet;
}
public synchronized boolean isInstantiated()
{
return theServlet != null;
}
private void loadIfNecessary(HttpServletRequest req, HttpServletResponse res)
throws JasperException, ServletException, FileNotFoundException
{
// First try context attribute; if that fails then use the
// classpath init parameter.
// Should I try to concatenate them if both are non-null?
String cp = (String) context.getAttribute(Constants.SERVLET_CLASSPATH);
String accordingto;
if(cp == null || cp.equals("")) {
accordingto = "according to the init parameter";
cp = options.getClassPath();
} else
accordingto = "according to the Servlet Engine";
Constants.message("jsp.message.cp_is",
new Object[] {
accordingto,
cp == null ? "" : cp
},
Logger.INFORMATION);
loadJSP(jspUri, cp, isErrorPage, req, res);
}
public void service(HttpServletRequest request,
HttpServletResponse response,
boolean precompile)
throws ServletException, IOException, FileNotFoundException
{
Servlet servlet = null;
try {
loadIfNecessary(request, response);
servlet = getServlet();
// If a page is to only to be precompiled return.
if(precompile)
return;
if(servlet instanceof SingleThreadModel) {
// sync on the wrapper so that the freshness
// of the page is determined right before servicing
synchronized (this) {
servlet.service(request, response);
}
} else {
servlet.service(request, response);
}
} catch(FileNotFoundException ex) {
try {
if(insecure_TMI) {
response.sendError(HttpServletResponse.SC_NOT_FOUND,
Constants.getString
("jsp.error.file.not.found.TMI",
new Object[] {
ex.getMessage()
}));
} else {
response.sendError(HttpServletResponse.SC_NOT_FOUND,
Constants.getString
("jsp.error.file.not.found",
new Object[] {
// Too Much Information -- ex.getMessage()
}));
}
} catch(IllegalStateException ise) {
// logs are presumed to be secure, thus the TMI info can be logged
Constants.jasperLog.log(Constants.getString
("jsp.error.file.not.found.TMI",
new Object[] {
ex.getMessage()
}), ex,
Logger.ERROR);
// rethrow FileNotFoundException so someone higher up can handle
if(insecure_TMI)
throw ex;
else
throw new FileNotFoundException(Constants.getString
("jsp.error.file.not.found",
new Object[] {
// Too Much Information -- ex.getMessage()
}));
}
return;
}
}
public void destroy()
{
if(theServlet != null)
theServlet.destroy();
}
}
protected ServletContext context = null;
protected Hashtable jsps = new Hashtable();
// protected Hashtable loadedJSPs = new Hashtable();
protected ServletConfig config;
protected JasperLoader loader;
protected Options options;
protected ClassLoader parentClassLoader;
protected ServletEngine engine;
protected String serverInfo;
/** Set to true to provide Too Much Information on errors */
private final boolean insecure_TMI = false;
static boolean firstTime = true;
static boolean jdk12=false;
static {
try {
Class.forName( "java.security.PrivilegedAction" );
jdk12=true;
} catch(Throwable ex ) {
}
}
public void init(ServletConfig config)
throws ServletException
{
super.init(config);
this.config = config;
this.context = config.getServletContext();
this.serverInfo = context.getServerInfo();
options = new EmbededServletOptions(config, context);
parentClassLoader = (ClassLoader) context.getAttribute(Constants.SERVLET_CLASS_LOADER);
if(parentClassLoader == null)
parentClassLoader = this.getClass().getClassLoader();
// getClass().getClassLoader() returns null in JDK 1.1.6/1.1.8
if(parentClassLoader != null) {
Constants.message("jsp.message.parent_class_loader_is",
new Object[] {
parentClassLoader.toString()
}, Logger.DEBUG);
} else {
Constants.message("jsp.message.parent_class_loader_is",
new Object[] {
"<none>"
}, Logger.DEBUG);
}
if( loader==null ) {
if( jdk12 ) {
try {
Class ld=Class.forName("org.apache.jasper.servlet.JasperLoader12");
loader=(JasperLoader)ld.newInstance();
} catch(Throwable t ) {
t.printStackTrace();
}
}
if( loader==null )
loader = new org.apache.jasper.servlet.JasperLoader();
loader.setParentClassLoader(parentClassLoader);
loader.setOptions(options);
Object pd=context.getAttribute("org.apache.tomcat.protection_domain");
loader.setProtectionDomain( pd );
}
if(firstTime) {
firstTime = false;
Constants.message("jsp.message.scratch.dir.is",
new Object[] {
options.getScratchDir().toString()
}, Logger.INFORMATION );
Constants.message("jsp.message.dont.modify.servlets", Logger.INFORMATION);
JspFactory.setDefaultFactory(new JspFactoryImpl());
}
}
private void serviceJspFile(HttpServletRequest request,
HttpServletResponse response, String jspUri,
Throwable exception, boolean precompile)
throws ServletException, IOException
{
boolean isErrorPage = exception != null;
JspServletWrapper wrapper = null;
/*
* Several threads may be handling requests for the same jspUri.
* Only one of them is allowed to create the JspServletWrapper.
*/
synchronized(jsps){
wrapper = (JspServletWrapper) jsps.get(jspUri);
if(wrapper == null) {
wrapper = new JspServletWrapper(jspUri, isErrorPage);
jsps.put(jspUri, wrapper);
}
}
wrapper.service(request, response, precompile);
}
boolean preCompile(HttpServletRequest request)
throws ServletException
{
boolean precompile = false;
String precom = request.getParameter(Constants.PRECOMPILE);
String qString = request.getQueryString();
if(precom != null) {
if(precom.equals("true"))
precompile = true;
else if(precom.equals("false"))
precompile = false;
else {
// This is illegal.
throw new ServletException("Can't have request parameter " +
" jsp_precomile set to " + precom);
}
} else if(qString != null && (qString.startsWith(Constants.PRECOMPILE) ||
qString.indexOf("&" + Constants.PRECOMPILE)
!= -1))
precompile = true;
return precompile;
}
public void service (HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException
{
try {
String includeUri
= (String) request.getAttribute(Constants.INC_SERVLET_PATH);
String jspUri;
if(includeUri == null)
jspUri = request.getServletPath();
else
jspUri = includeUri;
// System.out.println("JspServletWrapper: " + includeUri + " " +
// jspUri +
// (String) request.getAttribute(
// Constants.INC_REQUEST_URI));
boolean precompile = preCompile(request);
Logger jasperLog = Constants.jasperLog;
if(jasperLog != null &&
jasperLog.matchVerbosityLevel(Logger.INFORMATION)) {
jasperLog.log("JspEngine --> "+jspUri);
jasperLog.log("\t ServletPath: "+request.getServletPath());
jasperLog.log("\t PathInfo: "+request.getPathInfo());
jasperLog.log("\t RealPath: "
+getServletConfig().getServletContext().getRealPath(jspUri));
jasperLog.log("\t RequestURI: "+request.getRequestURI());
jasperLog.log("\t QueryString: "+request.getQueryString());
jasperLog.log("\t Request Params: ");
Enumeration e = request.getParameterNames();
while(e.hasMoreElements()) {
String name = (String) e.nextElement();
jasperLog.log("\t\t "+name+" = "+request.getParameter(name));
}
}
serviceJspFile(request, response, jspUri, null, precompile);
} catch(RuntimeException e) {
throw e;
} catch(ServletException e) {
throw e;
} catch(IOException e) {
throw e;
} catch(Throwable e) {
throw new ServletException(e);
}
// It's better to throw the exception - we don't
// know if we can deal with sendError ( buffer may be
// commited )
// catch (Throwable t) {
// unknownException(response, t);
// }
}
public void destroy() {
if(Constants.jasperLog != null)
Constants.jasperLog.log("JspServlet.destroy()", Logger.INFORMATION);
Enumeration servlets = jsps.elements();
while(servlets.hasMoreElements())
((JspServletWrapper) servlets.nextElement()).destroy();
}
/* Check if we need to reload a JSP page.
*
* Side-effect: re-compile the JSP page.
*
* @param classpath explicitly set the JSP compilation path.
* @return true if JSP files is newer
*/
boolean loadJSP(String jspUri, String classpath,
boolean isErrorPage, HttpServletRequest req, HttpServletResponse res)
throws JasperException, FileNotFoundException
{
// Loader knows how to set the right priviledges, and call
// doLoadeJsp
return loader.loadJSP( this,jspUri, classpath, isErrorPage, req, res );
}
/* Check if we need to reload a JSP page.
*
* Side-effect: re-compile the JSP page.
*
* @param classpath explicitly set the JSP compilation path.
* @return true if JSP files is newer
*/
/*
* A word about the thread synchronization below. The call to
* compiler.isOutDated() is outside the synchronization block on purpose.
* The expectation is that for the vast majority of cases the JSP source file
* will not have changed and there will be no need to recompile the
* implementation class. For those cases when a compile is required, we
* enter a block that is synchronized on the JspServletWrapper object for
* this JSP page. Because the initial out dated check is unsynchronized, it
* is possible for more than one request to attempt to enter the synchronized
* compile block. The compile() method contains performs an outdated check
* of its own. The first thread into the block will cause a compile, the
* subsequent threads will essentially skip the compilation and instantiation
* steps.
*
* One other thing to note is that there is a window of time between the
* compiler.compile() call and the end of the synchronized block where a new
* thread entering doLoadJSP() will be told that that implementation class is
* up to date even though the code in the synchronized block has not
* completed loading and instantiating the class. In this case doLoadJSP()
* will return false without attempting to compile the class. This is OK
* because the JspServletWrapper.getServlet() method used by the
* JspServletWrapper.service() method is synchronized. Thus, the service
* method will not receive the servlet class until it has been completely loaded and
* instantiated.
*
* The bottom line is that we avoid synchronizing a fairly expensive
* operation (isOutDated) but pay a small price of some unnecessary
* compilation attempts in the atypical case of a modified JSP file.
*/
protected boolean doLoadJSP(String jspUri, String classpath,
boolean isErrorPage, HttpServletRequest req, HttpServletResponse res)
throws JasperException, FileNotFoundException
{
JspServletWrapper jsw=(JspServletWrapper) jsps.get(jspUri);
if( jsw==null ) {
throw new JasperException("Can't happen - JspServletWrapper=null");
}
JspCompilationContext ctxt = new JspEngineContext(loader, classpath,
context, jspUri,
isErrorPage, options,
req, res);
boolean outDated = false;
Compiler compiler = null;
synchronized(jsw){
/*
* Creating a compiler opens the associated .class file (if it exists)
* and reads the actual class name. If we allow a compiler to be
* created while a compile is going on then bad things can happen.
*/
compiler = ctxt.createCompiler();
}
try {
outDated = compiler.isOutDated();
if(!jsw.isInstantiated() || outDated ) {
synchronized(jsw){
outDated = compiler.compile();
if(!jsw.isInstantiated() || outDated) {
if( null ==ctxt.getServletClassName() ) {
compiler.computeServletClassName();
}
jsw.instantiateServlet(loader.loadClass(ctxt.getFullClassName()));
}
}
}
} catch(FileNotFoundException ex) {
compiler.removeGeneratedFiles();
throw ex;
} catch(JasperException ex) {
throw ex;
} catch(ClassNotFoundException cex) {
throw new JasperException(Constants.getString("jsp.error.unable.load"),
cex);
} catch(Exception ex) {
throw new JasperException(Constants.getString("jsp.error.unable.compile"),
ex);
}
return outDated;
}
/**
* Determines whether the current JSP class is older than the JSP file
* from whence it came
*/
public boolean isOutDated(File jsp, JspCompilationContext ctxt,
Mangler mangler ) {
File jspReal = null;
boolean outDated;
jspReal = new File(ctxt.getRealPath(jsp.getPath()));
File classFile = new File(mangler.getClassFileName());
if(classFile.exists()) {
outDated = classFile.lastModified() < jspReal.lastModified();
} else {
outDated = true;
}
return outDated;
}
}