/*
* 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.catalina.loader;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FilePermission;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.jar.JarFile;
import javax.management.ObjectName;
import javax.servlet.ServletContext;
import org.apache.catalina.Context;
import org.apache.catalina.Globals;
import org.apache.catalina.Lifecycle;
import org.apache.catalina.LifecycleException;
import org.apache.catalina.LifecycleState;
import org.apache.catalina.Loader;
import org.apache.catalina.WebResource;
import org.apache.catalina.WebResourceRoot;
import org.apache.catalina.util.LifecycleMBeanBase;
import org.apache.tomcat.util.ExceptionUtils;
import org.apache.tomcat.util.modeler.Registry;
import org.apache.tomcat.util.res.StringManager;
/**
* Classloader implementation which is specialized for handling web
* applications in the most efficient way, while being Catalina aware (all
* accesses to resources are made through {@link WebResourceRoot}).
* This class loader supports detection of modified
* Java classes, which can be used to implement auto-reload support.
* <p>
* This class loader is configured by adding the pathnames of directories,
* JAR files, and ZIP files with the <code>addRepository()</code> method,
* prior to calling <code>start()</code>. When a new class is required,
* these repositories will be consulted first to locate the class. If it
* is not present, the system class loader will be used instead.
*
* @author Craig R. McClanahan
* @author Remy Maucherat
* @version $Id: WebappLoader.java 1524528 2013-09-18 18:48:41Z markt $
*/
public class WebappLoader extends LifecycleMBeanBase
implements Loader, PropertyChangeListener {
// ----------------------------------------------------------- Constructors
/**
* Construct a new WebappLoader with no defined parent class loader
* (so that the actual parent will be the system class loader).
*/
public WebappLoader() {
this(null);
}
/**
* Construct a new WebappLoader with the specified class loader
* to be defined as the parent of the ClassLoader we ultimately create.
*
* @param parent The parent class loader
*/
public WebappLoader(ClassLoader parent) {
super();
this.parentClassLoader = parent;
}
// ----------------------------------------------------- Instance Variables
/**
* The class loader being managed by this Loader component.
*/
private WebappClassLoader classLoader = null;
/**
* The Context with which this Loader has been associated.
*/
private Context context = null;
/**
* The "follow standard delegation model" flag that will be used to
* configure our ClassLoader.
*/
private boolean delegate = false;
/**
* The Java class name of the ClassLoader implementation to be used.
* This class should extend WebappClassLoader, otherwise, a different
* loader implementation must be used.
*/
private String loaderClass =
"org.apache.catalina.loader.WebappClassLoader";
/**
* The parent class loader of the class loader we will create.
*/
private ClassLoader parentClassLoader = null;
/**
* The reloadable flag for this Loader.
*/
private boolean reloadable = false;
/**
* The string manager for this package.
*/
protected static final StringManager sm =
StringManager.getManager(Constants.Package);
/**
* The property change support for this component.
*/
protected final PropertyChangeSupport support = new PropertyChangeSupport(this);
/**
* Classpath set in the loader.
*/
private String classpath = null;
/**
* Repositories that are set in the loader, for JMX.
*/
private ArrayList<String> loaderRepositories = null;
// ------------------------------------------------------------- Properties
/**
* Return the Java class loader to be used by this Container.
*/
@Override
public ClassLoader getClassLoader() {
return classLoader;
}
@Override
public Context getContext() {
return context;
}
@Override
public void setContext(Context context) {
if (this.context == context) {
return;
}
if (getState().isAvailable()) {
throw new IllegalStateException(
sm.getString("webappLoader.setContext.ise"));
}
// Deregister from the old Context (if any)
if (this.context != null) {
this.context.removePropertyChangeListener(this);
}
// Process this property change
Context oldContext = this.context;
this.context = context;
support.firePropertyChange("context", oldContext, this.context);
// Register with the new Container (if any)
if (this.context != null) {
setReloadable(this.context.getReloadable());
this.context.addPropertyChangeListener(this);
}
}
/**
* Return the "follow standard delegation model" flag used to configure
* our ClassLoader.
*/
@Override
public boolean getDelegate() {
return (this.delegate);
}
/**
* Set the "follow standard delegation model" flag used to configure
* our ClassLoader.
*
* @param delegate The new flag
*/
@Override
public void setDelegate(boolean delegate) {
boolean oldDelegate = this.delegate;
this.delegate = delegate;
support.firePropertyChange("delegate", Boolean.valueOf(oldDelegate),
Boolean.valueOf(this.delegate));
}
/**
* Return the ClassLoader class name.
*/
public String getLoaderClass() {
return (this.loaderClass);
}
/**
* Set the ClassLoader class name.
*
* @param loaderClass The new ClassLoader class name
*/
public void setLoaderClass(String loaderClass) {
this.loaderClass = loaderClass;
}
/**
* Return the reloadable flag for this Loader.
*/
@Override
public boolean getReloadable() {
return (this.reloadable);
}
/**
* Set the reloadable flag for this Loader.
*
* @param reloadable The new reloadable flag
*/
@Override
public void setReloadable(boolean reloadable) {
// Process this property change
boolean oldReloadable = this.reloadable;
this.reloadable = reloadable;
support.firePropertyChange("reloadable",
Boolean.valueOf(oldReloadable),
Boolean.valueOf(this.reloadable));
}
// --------------------------------------------------------- Public Methods
/**
* Add a property change listener to this component.
*
* @param listener The listener to add
*/
@Override
public void addPropertyChangeListener(PropertyChangeListener listener) {
support.addPropertyChangeListener(listener);
}
/**
* Execute a periodic task, such as reloading, etc. This method will be
* invoked inside the classloading context of this container. Unexpected
* throwables will be caught and logged.
*/
@Override
public void backgroundProcess() {
if (reloadable && modified()) {
try {
Thread.currentThread().setContextClassLoader
(WebappLoader.class.getClassLoader());
if (context != null) {
context.reload();
}
} finally {
if (context != null && context.getLoader() != null) {
Thread.currentThread().setContextClassLoader
(context.getLoader().getClassLoader());
}
}
} else {
closeJARs(false);
}
}
public String[] getLoaderRepositories() {
if( loaderRepositories==null ) return null;
String res[]=new String[ loaderRepositories.size()];
loaderRepositories.toArray(res);
return res;
}
public String getLoaderRepositoriesString() {
String repositories[]=getLoaderRepositories();
StringBuilder sb=new StringBuilder();
for( int i=0; i<repositories.length ; i++ ) {
sb.append( repositories[i]).append(":");
}
return sb.toString();
}
/**
* Classpath, as set in org.apache.catalina.jsp_classpath context
* property
*
* @return The classpath
*/
public String getClasspath() {
return classpath;
}
/**
* Has the internal repository associated with this Loader been modified,
* such that the loaded classes should be reloaded?
*/
@Override
public boolean modified() {
return classLoader != null ? classLoader.modified() : false ;
}
/**
* Used to periodically signal to the classloader to release JAR resources.
*/
public void closeJARs(boolean force) {
if (classLoader !=null) {
classLoader.closeJARs(force);
}
}
/**
* Remove a property change listener from this component.
*
* @param listener The listener to remove
*/
@Override
public void removePropertyChangeListener(PropertyChangeListener listener) {
support.removePropertyChangeListener(listener);
}
/**
* Return a String representation of this component.
*/
@Override
public String toString() {
StringBuilder sb = new StringBuilder("WebappLoader[");
if (context != null)
sb.append(context.getName());
sb.append("]");
return (sb.toString());
}
/**
* Start associated {@link ClassLoader} and implement the requirements
* of {@link org.apache.catalina.util.LifecycleBase#startInternal()}.
*
* @exception LifecycleException if this component detects a fatal error
* that prevents this component from being used
*/
@Override
protected void startInternal() throws LifecycleException {
if (log.isDebugEnabled())
log.debug(sm.getString("webappLoader.starting"));
if (context.getResources() == null) {
log.info("No resources for " + context);
setState(LifecycleState.STARTING);
return;
}
// Construct a class loader based on our current repositories list
try {
classLoader = createClassLoader();
classLoader.setResources(context.getResources());
classLoader.setDelegate(this.delegate);
// Configure our repositories
setRepositories();
setClassPath();
setPermissions();
((Lifecycle) classLoader).start();
String contextName = context.getName();
if (!contextName.startsWith("/")) {
contextName = "/" + contextName;
}
ObjectName cloname = new ObjectName(context.getDomain() +
":type=WebappClassLoader,context=" + contextName +
",host=" + context.getParent().getName());
Registry.getRegistry(null, null)
.registerComponent(classLoader, cloname, null);
} catch (Throwable t) {
t = ExceptionUtils.unwrapInvocationTargetException(t);
ExceptionUtils.handleThrowable(t);
log.error( "LifecycleException ", t );
throw new LifecycleException("start: ", t);
}
setState(LifecycleState.STARTING);
}
/**
* Stop associated {@link ClassLoader} and implement the requirements
* of {@link org.apache.catalina.util.LifecycleBase#stopInternal()}.
*
* @exception LifecycleException if this component detects a fatal error
* that prevents this component from being used
*/
@Override
protected void stopInternal() throws LifecycleException {
if (log.isDebugEnabled())
log.debug(sm.getString("webappLoader.stopping"));
setState(LifecycleState.STOPPING);
// Remove context attributes as appropriate
ServletContext servletContext = context.getServletContext();
servletContext.removeAttribute(Globals.CLASS_PATH_ATTR);
// Throw away our current class loader
if (classLoader != null) {
((Lifecycle) classLoader).stop();
}
try {
String contextName = context.getName();
if (!contextName.startsWith("/")) {
contextName = "/" + contextName;
}
ObjectName cloname = new ObjectName(context.getDomain() +
":type=WebappClassLoader,context=" + contextName +
",host=" + context.getParent().getName());
Registry.getRegistry(null, null).unregisterComponent(cloname);
} catch (Exception e) {
log.error("LifecycleException ", e);
}
classLoader = null;
}
// ----------------------------------------- PropertyChangeListener Methods
/**
* Process property change events from our associated Context.
*
* @param event The property change event that has occurred
*/
@Override
public void propertyChange(PropertyChangeEvent event) {
// Validate the source of this event
if (!(event.getSource() instanceof Context))
return;
// Process a relevant property change
if (event.getPropertyName().equals("reloadable")) {
try {
setReloadable
( ((Boolean) event.getNewValue()).booleanValue() );
} catch (NumberFormatException e) {
log.error(sm.getString("webappLoader.reloadable",
event.getNewValue().toString()));
}
}
}
// ------------------------------------------------------- Private Methods
/**
* Create associated classLoader.
*/
private WebappClassLoader createClassLoader()
throws Exception {
Class<?> clazz = Class.forName(loaderClass);
WebappClassLoader classLoader = null;
if (parentClassLoader == null) {
parentClassLoader = context.getParentClassLoader();
}
Class<?>[] argTypes = { ClassLoader.class };
Object[] args = { parentClassLoader };
Constructor<?> constr = clazz.getConstructor(argTypes);
classLoader = (WebappClassLoader) constr.newInstance(args);
return classLoader;
}
/**
* Configure associated class loader permissions.
*/
private void setPermissions() {
if (!Globals.IS_SECURITY_ENABLED)
return;
if (context == null)
return;
// Tell the class loader the root of the context
ServletContext servletContext = context.getServletContext();
// Assigning permissions for the work directory
File workDir =
(File) servletContext.getAttribute(ServletContext.TEMPDIR);
if (workDir != null) {
try {
String workDirPath = workDir.getCanonicalPath();
classLoader.addPermission
(new FilePermission(workDirPath, "read,write"));
classLoader.addPermission
(new FilePermission(workDirPath + File.separator + "-",
"read,write,delete"));
} catch (IOException e) {
// Ignore
}
}
try {
URL rootURL = servletContext.getResource("/");
classLoader.addPermission(rootURL);
String contextRoot = servletContext.getRealPath("/");
if (contextRoot != null) {
try {
contextRoot = (new File(contextRoot)).getCanonicalPath();
classLoader.addPermission(contextRoot);
} catch (IOException e) {
// Ignore
}
}
URL classesURL = servletContext.getResource("/WEB-INF/classes/");
classLoader.addPermission(classesURL);
URL libURL = servletContext.getResource("/WEB-INF/lib/");
classLoader.addPermission(libURL);
if (contextRoot != null) {
if (libURL != null) {
File rootDir = new File(contextRoot);
File libDir = new File(rootDir, "WEB-INF/lib/");
try {
String path = libDir.getCanonicalPath();
classLoader.addPermission(path);
} catch (IOException e) {
// Ignore
}
}
} else {
if (workDir != null) {
if (libURL != null) {
File libDir = new File(workDir, "WEB-INF/lib/");
try {
String path = libDir.getCanonicalPath();
classLoader.addPermission(path);
} catch (IOException e) {
// Ignore
}
}
if (classesURL != null) {
File classesDir = new File(workDir, "WEB-INF/classes/");
try {
String path = classesDir.getCanonicalPath();
classLoader.addPermission(path);
} catch (IOException e) {
// Ignore
}
}
}
}
} catch (MalformedURLException e) {
// Ignore
}
}
/**
* Configure the repositories for our class loader, based on the
* associated Context.
* @throws IOException
*/
private void setRepositories() throws IOException {
if (context == null)
return;
ServletContext servletContext = context.getServletContext();
if (servletContext == null)
return;
loaderRepositories=new ArrayList<>();
// Loading the work directory
File workDir =
(File) servletContext.getAttribute(ServletContext.TEMPDIR);
if (workDir == null) {
log.info("No work dir for " + servletContext);
}
if( log.isDebugEnabled() && workDir != null)
log.debug(sm.getString("webappLoader.deploy", workDir.getAbsolutePath()));
classLoader.setWorkDir(workDir);
WebResourceRoot resources = context.getResources();
// Setting up the class repository (/WEB-INF/classes), if it exists
String classesPath = "/WEB-INF/classes";
WebResource classes = resources.getResource(classesPath);
if (classes.isDirectory()) {
if(log.isDebugEnabled())
log.debug(sm.getString("webappLoader.classDeploy", classesPath,
classes.getURL().toExternalForm()));
// Adding the repository to the class loader
classLoader.setRepository(classesPath + "/", classes);
loaderRepositories.add(classesPath + "/" );
}
// Setting up the JAR repository (/WEB-INF/lib), if it exists
// TODO Simplify this in a similar manner to WEB-INF/classes
String libPath = "/WEB-INF/lib";
classLoader.setJarPath(libPath);
WebResource libDir = resources.getResource(libPath);
if (libDir.isDirectory()) {
boolean copyJars = false;
String absoluteLibPath = libDir.getCanonicalPath();
File destDir = null;
if (absoluteLibPath != null) {
destDir = new File(absoluteLibPath);
} else {
copyJars = true;
destDir = new File(workDir, libPath);
if (!destDir.mkdirs() && !destDir.isDirectory()) {
throw new IOException(
sm.getString("webappLoader.mkdirFailure"));
}
}
WebResource[] jars = resources.listResources(libPath);
for (WebResource jar : jars) {
String jarName = jar.getName();
if (!jarName.endsWith(".jar"))
continue;
String filename = libPath + "/" + jarName;
// Copy JAR in the work directory, always (the JAR file
// would get locked otherwise, which would make it
// impossible to update it or remove it at runtime)
File destFile = new File(destDir, jarName);
if (log.isDebugEnabled()) {
log.debug(sm.getString("webappLoader.jarDeploy", filename,
destFile.getAbsolutePath()));
}
// Bug 45403 - Check that the resource is readable
if (!jar.canRead()) {
IOException ioe = new IOException(sm.getString(
"webappLoader.readFailure", filename));
throw ioe;
}
if (copyJars) {
if (!copy(jar.getInputStream(),destFile)) {
throw new IOException(
sm.getString("webappLoader.copyFailure"));
}
}
try {
JarFile jarFile = new JarFile(destFile);
classLoader.addJar(filename, jarFile, destFile);
} catch (Exception ex) {
// Catch the exception if there is an empty jar file
// Should ignore and continue loading other jar files
// in the dir
}
loaderRepositories.add( filename );
}
}
}
/**
* Set the appropriate context attribute for our class path. This
* is required only because Jasper depends on it.
*/
private void setClassPath() {
// Validate our current state information
if (context == null)
return;
ServletContext servletContext = context.getServletContext();
if (servletContext == null)
return;
StringBuilder classpath = new StringBuilder();
// Assemble the class path information from our class loader chain
ClassLoader loader = getClassLoader();
if (delegate && loader != null) {
// Skip the webapp loader for now as delegation is enabled
loader = loader.getParent();
}
while (loader != null) {
if (!buildClassPath(servletContext, classpath, loader)) {
break;
}
loader = loader.getParent();
}
if (delegate) {
// Delegation was enabled, go back and add the webapp paths
loader = getClassLoader();
if (loader != null) {
buildClassPath(servletContext, classpath, loader);
}
}
this.classpath=classpath.toString();
// Store the assembled class path as a servlet context attribute
servletContext.setAttribute(Globals.CLASS_PATH_ATTR,
classpath.toString());
}
private boolean buildClassPath(ServletContext servletContext,
StringBuilder classpath, ClassLoader loader) {
if (loader instanceof URLClassLoader) {
URL repositories[] =
((URLClassLoader) loader).getURLs();
for (int i = 0; i < repositories.length; i++) {
String repository = repositories[i].toString();
if (repository.startsWith("file://"))
repository = utf8Decode(repository.substring(7));
else if (repository.startsWith("file:"))
repository = utf8Decode(repository.substring(5));
else if (repository.startsWith("jndi:"))
repository =
servletContext.getRealPath(repository.substring(5));
else
continue;
if (repository == null)
continue;
if (classpath.length() > 0)
classpath.append(File.pathSeparator);
classpath.append(repository);
}
} else {
String cp = getClasspath(loader);
if (cp == null) {
log.info( "Unknown loader " + loader + " " + loader.getClass());
} else {
if (classpath.length() > 0)
classpath.append(File.pathSeparator);
classpath.append(cp);
}
return false;
}
return true;
}
private String utf8Decode(String input) {
String result = null;
try {
result = URLDecoder.decode(input, "UTF-8");
} catch (UnsupportedEncodingException uee) {
// Impossible. All JVMs are required to support UTF-8.
}
return result;
}
// try to extract the classpath from a loader that is not URLClassLoader
private String getClasspath( ClassLoader loader ) {
try {
Method m=loader.getClass().getMethod("getClasspath", new Class[] {});
if( log.isTraceEnabled())
log.trace("getClasspath " + m );
if( m==null ) return null;
Object o=m.invoke( loader, new Object[] {} );
if( log.isDebugEnabled() )
log.debug("gotClasspath " + o);
if( o instanceof String )
return (String)o;
return null;
} catch( Exception ex ) {
Throwable t = ExceptionUtils.unwrapInvocationTargetException(ex);
ExceptionUtils.handleThrowable(t);
if (log.isDebugEnabled())
log.debug("getClasspath ", ex);
}
return null;
}
/**
* Copy a file to the specified temp directory. This is required only
* because Jasper depends on it.
*/
private boolean copy(InputStream is, File file) {
try (FileOutputStream os = new FileOutputStream(file)){
byte[] buf = new byte[4096];
while (true) {
int len = is.read(buf);
if (len < 0)
break;
os.write(buf, 0, len);
}
} catch (IOException e) {
return false;
} finally {
try {
is.close();
} catch (IOException e) {
// Ignore
}
}
return true;
}
private static final org.apache.juli.logging.Log log=
org.apache.juli.logging.LogFactory.getLog( WebappLoader.class );
@Override
protected String getDomainInternal() {
return context.getDomain();
}
@Override
protected String getObjectNameKeyProperties() {
StringBuilder name = new StringBuilder("type=Loader");
name.append(",context=");
String contextName = context.getName();
if (!contextName.startsWith("/")) {
name.append("/");
}
name.append(contextName);
name.append(",host=");
name.append(context.getParent().getName());
return name.toString();
}
}