JspRuntimeContext.java
/*
* 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.jasper.compiler;
import java.io.File;
import java.io.FileNotFoundException;
import java.net.URISyntaxException;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicInteger;
import jakarta.servlet.ServletContext;
import jakarta.servlet.ServletException;
import org.apache.jasper.JspCompilationContext;
import org.apache.jasper.Options;
import org.apache.jasper.runtime.ExceptionUtils;
import org.apache.jasper.servlet.JspServletWrapper;
import org.apache.jasper.util.FastRemovalDequeue;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
/**
* Class for tracking JSP compile time file dependencies when the
* >%@include file="..."%< directive is used.
*
* A background thread periodically checks the files a JSP page
* is dependent upon. If a dependent file changes the JSP page
* which included it is recompiled.
*
* Only used if a web application context is a directory.
*
* @author Glenn L. Nielsen
*/
public final class JspRuntimeContext {
/**
* Logger
*/
private final Log log = LogFactory.getLog(JspRuntimeContext.class); // must not be static
/**
* Counts how many times the webapp's JSPs have been reloaded.
*/
private final AtomicInteger jspReloadCount = new AtomicInteger(0);
/**
* Counts how many times JSPs have been unloaded in this webapp.
*/
private final AtomicInteger jspUnloadCount = new AtomicInteger(0);
// ----------------------------------------------------------- Constructors
/**
* Create a JspRuntimeContext for a web application context.
*
* Loads in any previously generated dependencies from file.
*
* @param context ServletContext for web application
* @param options The main Jasper options
*/
public JspRuntimeContext(ServletContext context, Options options) {
this.context = context;
this.options = options;
// Get the parent class loader
ClassLoader loader = Thread.currentThread().getContextClassLoader();
if (loader == null) {
loader = this.getClass().getClassLoader();
}
if (log.isTraceEnabled()) {
if (loader != null) {
log.trace(Localizer.getMessage("jsp.message.parent_class_loader_is",
loader.toString()));
} else {
log.trace(Localizer.getMessage("jsp.message.parent_class_loader_is",
"<none>"));
}
}
parentClassLoader = loader;
classpath = initClassPath();
if (context instanceof org.apache.jasper.servlet.JspCServletContext) {
return;
}
// If this web application context is running from a
// directory, start the background compilation thread
String appBase = context.getRealPath("/");
if (!options.getDevelopment()
&& appBase != null
&& options.getCheckInterval() > 0) {
lastCompileCheck = System.currentTimeMillis();
}
if (options.getMaxLoadedJsps() > 0) {
jspQueue = new FastRemovalDequeue<>(options.getMaxLoadedJsps());
if (log.isTraceEnabled()) {
log.trace(Localizer.getMessage("jsp.message.jsp_queue_created",
"" + options.getMaxLoadedJsps(), context.getContextPath()));
}
}
/* Init parameter is in seconds, locally we use milliseconds */
jspIdleTimeout = options.getJspIdleTimeout() * 1000;
}
// ----------------------------------------------------- Instance Variables
/**
* This web applications ServletContext
*/
private final ServletContext context;
private final Options options;
private final ClassLoader parentClassLoader;
private final String classpath;
private volatile long lastCompileCheck = -1L;
private volatile long lastJspQueueUpdate = System.currentTimeMillis();
/* JSP idle timeout in milliseconds */
private long jspIdleTimeout;
/**
* Maps JSP pages to their JspServletWrapper's
*/
private final Map<String, JspServletWrapper> jsps = new ConcurrentHashMap<>();
/**
* Keeps JSP pages ordered by last access.
*/
private FastRemovalDequeue<JspServletWrapper> jspQueue = null;
/**
* Map of class name to associated source map. This is maintained here as
* multiple JSPs can depend on the same file (included JSP, tag file, etc.)
* so a web application scoped Map is required.
*/
private final Map<String,SmapStratum> smaps = new ConcurrentHashMap<>();
/**
* Flag that indicates if a background compilation check is in progress.
*/
private volatile boolean compileCheckInProgress = false;
// ------------------------------------------------------ Public Methods
/**
* Add a new JspServletWrapper.
*
* @param jspUri JSP URI
* @param jsw Servlet wrapper for JSP
*/
public void addWrapper(String jspUri, JspServletWrapper jsw) {
jsps.put(jspUri, jsw);
}
/**
* Get an already existing JspServletWrapper.
*
* @param jspUri JSP URI
* @return JspServletWrapper for JSP
*/
public JspServletWrapper getWrapper(String jspUri) {
return jsps.get(jspUri);
}
/**
* Remove a JspServletWrapper.
*
* @param jspUri JSP URI of JspServletWrapper to remove
*/
public void removeWrapper(String jspUri) {
jsps.remove(jspUri);
}
/**
* Push a newly compiled JspServletWrapper into the queue at first
* execution of jsp. Destroy any JSP that has been replaced in the queue.
*
* @param jsw Servlet wrapper for jsp.
* @return an unloadHandle that can be pushed to front of queue at later execution times.
* */
public FastRemovalDequeue<JspServletWrapper>.Entry push(JspServletWrapper jsw) {
if (log.isTraceEnabled()) {
log.trace(Localizer.getMessage("jsp.message.jsp_added",
jsw.getJspUri(), context.getContextPath()));
}
FastRemovalDequeue<JspServletWrapper>.Entry entry = jspQueue.push(jsw);
JspServletWrapper replaced = entry.getReplaced();
if (replaced != null) {
if (log.isTraceEnabled()) {
log.trace(Localizer.getMessage("jsp.message.jsp_removed_excess",
replaced.getJspUri(), context.getContextPath()));
}
unloadJspServletWrapper(replaced);
entry.clearReplaced();
}
return entry;
}
/**
* Push unloadHandle for JspServletWrapper to front of the queue.
*
* @param unloadHandle the unloadHandle for the jsp.
* */
public void makeYoungest(FastRemovalDequeue<JspServletWrapper>.Entry unloadHandle) {
if (log.isTraceEnabled()) {
JspServletWrapper jsw = unloadHandle.getContent();
log.trace(Localizer.getMessage("jsp.message.jsp_queue_update",
jsw.getJspUri(), context.getContextPath()));
}
jspQueue.moveFirst(unloadHandle);
}
/**
* Returns the number of JSPs for which JspServletWrappers exist, i.e.,
* the number of JSPs that have been loaded into the webapp.
*
* @return The number of JSPs that have been loaded into the webapp
*/
public int getJspCount() {
return jsps.size();
}
/**
* Get the parent ClassLoader.
*
* @return ClassLoader parent
*/
public ClassLoader getParentClassLoader() {
return parentClassLoader;
}
/**
* Process a "destroy" event for this web application context.
*/
public void destroy() {
for (JspServletWrapper jspServletWrapper : jsps.values()) {
jspServletWrapper.destroy();
}
}
/**
* Increments the JSP reload counter.
*/
public void incrementJspReloadCount() {
jspReloadCount.incrementAndGet();
}
/**
* Resets the JSP reload counter.
*
* @param count Value to which to reset the JSP reload counter
*/
public void setJspReloadCount(int count) {
jspReloadCount.set(count);
}
/**
* Gets the current value of the JSP reload counter.
*
* @return The current value of the JSP reload counter
*/
public int getJspReloadCount() {
return jspReloadCount.intValue();
}
/**
* Gets the number of JSPs that are in the JSP limiter queue
*
* @return The number of JSPs (in the webapp with which this JspServlet is
* associated) that are in the JSP limiter queue
*/
public int getJspQueueLength() {
if (jspQueue != null) {
return jspQueue.getSize();
}
return -1;
}
/**
* Gets the number of JSPs that have been unloaded.
*
* @return The number of JSPs (in the webapp with which this JspServlet is
* associated) that have been unloaded
*/
public int getJspUnloadCount() {
return jspUnloadCount.intValue();
}
/**
* Method used by background thread to check the JSP dependencies
* registered with this class for JSP's.
*/
public void checkCompile() {
if (lastCompileCheck < 0) {
// Checking was disabled
return;
}
long now = System.currentTimeMillis();
if (now > (lastCompileCheck + (options.getCheckInterval() * 1000L))) {
lastCompileCheck = now;
} else {
return;
}
List<JspServletWrapper> wrappersToReload = new ArrayList<>();
// Tell JspServletWrapper to ignore the reload attribute while this
// check is in progress. See BZ 62603.
compileCheckInProgress = true;
Object [] wrappers = jsps.values().toArray();
for (Object wrapper : wrappers) {
JspServletWrapper jsw = (JspServletWrapper) wrapper;
JspCompilationContext ctxt = jsw.getJspEngineContext();
// Sync on JspServletWrapper when calling ctxt.compile()
synchronized (jsw) {
try {
ctxt.compile();
if (jsw.getReload()) {
wrappersToReload.add(jsw);
}
} catch (FileNotFoundException ex) {
ctxt.incrementRemoved();
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
jsw.getServletContext().log(Localizer.getMessage("jsp.error.backgroundCompilationFailed"), t);
}
}
}
// See BZ 62603.
// OK to process reload flag now.
compileCheckInProgress = false;
// Ensure all servlets and tags that need to be reloaded, are reloaded.
for (JspServletWrapper jsw : wrappersToReload) {
// Triggers reload
try {
if (jsw.isTagFile()) {
// Although this is a public method, all other paths to this
// method use this sync and it is required to prevent race
// conditions during the reload.
synchronized (this) {
jsw.loadTagFile();
}
} else {
jsw.getServlet();
}
} catch (ServletException e) {
jsw.getServletContext().log(Localizer.getMessage("jsp.error.reload"), e);
}
}
}
public boolean isCompileCheckInProgress() {
return compileCheckInProgress;
}
/**
* @return the classpath that is passed off to the Java compiler.
*/
public String getClassPath() {
return classpath;
}
/**
* @return Last time the update background task has run
*/
public long getLastJspQueueUpdate() {
return lastJspQueueUpdate;
}
public Map<String,SmapStratum> getSmaps() {
return smaps;
}
public Options getOptions() {
return options;
}
// -------------------------------------------------------- Private Methods
/**
* Method used to initialize classpath for compiles.
* @return the compilation classpath
*/
private String initClassPath() {
StringBuilder cpath = new StringBuilder();
if (parentClassLoader instanceof URLClassLoader) {
URL [] urls = ((URLClassLoader)parentClassLoader).getURLs();
for (URL url : urls) {
// Tomcat can use URLs other than file URLs. However, a protocol
// other than file: will generate a bad file system path, so
// only add file: protocol URLs to the classpath.
if (url.getProtocol().equals("file")) {
try {
// Need to decode the URL, primarily to convert %20
// sequences back to spaces
String decoded = url.toURI().getPath();
cpath.append(decoded + File.pathSeparator);
} catch (URISyntaxException e) {
log.warn(Localizer.getMessage("jsp.warning.classpathUrl"), e);
}
}
}
}
cpath.append(options.getScratchDir() + File.pathSeparator);
String cp = (String) context.getAttribute(options.getServletClasspathAttribute());
if (cp == null || cp.equals("")) {
cp = options.getClassPath();
}
String path = cpath.toString() + cp;
if(log.isTraceEnabled()) {
log.trace("Compilation classpath initialized: " + path);
}
return path;
}
private void unloadJspServletWrapper(JspServletWrapper jsw) {
removeWrapper(jsw.getJspUri());
synchronized(jsw) {
jsw.destroy();
}
jspUnloadCount.incrementAndGet();
}
/**
* Method used by background thread to check if any JSP's should be unloaded.
*/
public void checkUnload() {
if (log.isTraceEnabled()) {
int queueLength = -1;
if (jspQueue != null) {
queueLength = jspQueue.getSize();
}
log.trace(Localizer.getMessage("jsp.message.jsp_unload_check",
context.getContextPath(), "" + jsps.size(), "" + queueLength));
}
long now = System.currentTimeMillis();
if (jspIdleTimeout > 0) {
long unloadBefore = now - jspIdleTimeout;
Object [] wrappers = jsps.values().toArray();
for (Object wrapper : wrappers) {
JspServletWrapper jsw = (JspServletWrapper) wrapper;
synchronized (jsw) {
if (jsw.getLastUsageTime() < unloadBefore) {
if (log.isTraceEnabled()) {
log.trace(Localizer.getMessage("jsp.message.jsp_removed_idle",
jsw.getJspUri(), context.getContextPath(),
"" + (now - jsw.getLastUsageTime())));
}
if (jspQueue != null) {
jspQueue.remove(jsw.getUnloadHandle());
}
unloadJspServletWrapper(jsw);
}
}
}
}
lastJspQueueUpdate = now;
}
}