org.apache.catalina.loader.WebappLoader Maven / Gradle / Ivy
/*
* 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.OutputStream;
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.URLStreamHandlerFactory;
import java.util.ArrayList;
import java.util.jar.JarFile;
import javax.management.ObjectName;
import javax.naming.NameClassPair;
import javax.naming.NamingEnumeration;
import javax.naming.NamingException;
import javax.naming.directory.DirContext;
import javax.servlet.ServletContext;
import org.apache.catalina.Container;
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.core.StandardContext;
import org.apache.catalina.mbeans.MBeanUtils;
import org.apache.catalina.util.LifecycleMBeanBase;
import org.apache.naming.resources.DirContextURLStreamHandler;
import org.apache.naming.resources.DirContextURLStreamHandlerFactory;
import org.apache.naming.resources.Resource;
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 the DirContext interface).
* This class loader supports detection of modified
* Java classes, which can be used to implement auto-reload support.
*
* This class loader is configured by adding the pathnames of directories,
* JAR files, and ZIP files with the addRepository() method,
* prior to calling start(). 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 1064932 2011-01-29 00:00:50Z 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
/**
* First load of the class.
*/
private static boolean first = true;
/**
* The class loader being managed by this Loader component.
*/
private WebappClassLoader classLoader = null;
/**
* The Container with which this Loader has been associated.
*/
private Container container = null;
/**
* The "follow standard delegation model" flag that will be used to
* configure our ClassLoader.
*/
private boolean delegate = false;
/**
* The descriptive information about this Loader implementation.
*/
private static final String info =
"org.apache.catalina.loader.WebappLoader/1.0";
/**
* 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 set of repositories associated with this class loader.
*/
private String repositories[] = new String[0];
/**
* The string manager for this package.
*/
protected static final StringManager sm =
StringManager.getManager(Constants.Package);
/**
* The property change support for this component.
*/
protected 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 loaderRepositories = null;
/**
* Whether we should search the external repositories first
*/
private boolean searchExternalFirst = false;
// ------------------------------------------------------------- Properties
/**
* Return the Java class loader to be used by this Container.
*/
@Override
public ClassLoader getClassLoader() {
return classLoader;
}
/**
* Return the Container with which this Logger has been associated.
*/
@Override
public Container getContainer() {
return (container);
}
/**
* Set the Container with which this Logger has been associated.
*
* @param container The associated Container
*/
@Override
public void setContainer(Container container) {
// Deregister from the old Container (if any)
if ((this.container != null) && (this.container instanceof Context))
((Context) this.container).removePropertyChangeListener(this);
// Process this property change
Container oldContainer = this.container;
this.container = container;
support.firePropertyChange("container", oldContainer, this.container);
// Register with the new Container (if any)
if ((this.container != null) && (this.container instanceof Context)) {
setReloadable( ((Context) this.container).getReloadable() );
((Context) this.container).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 descriptive information about this Loader implementation and
* the corresponding version number, in the format
* <description>/<version>.
*/
@Override
public String getInfo() {
return (info);
}
/**
* 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));
}
/**
* @return Returns searchExternalFirst.
*/
public boolean getSearchExternalFirst() {
return searchExternalFirst;
}
/**
* @param searchExternalFirst Whether external repositories should be searched first
*/
public void setSearchExternalFirst(boolean searchExternalFirst) {
this.searchExternalFirst = searchExternalFirst;
if (classLoader != null) {
classLoader.setSearchExternalFirst(searchExternalFirst);
}
}
// --------------------------------------------------------- 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);
}
/**
* Add a new repository to the set of repositories for this class loader.
*
* @param repository Repository to be added
*/
@Override
public void addRepository(String repository) {
if (log.isDebugEnabled())
log.debug(sm.getString("webappLoader.addRepository", repository));
for (int i = 0; i < repositories.length; i++) {
if (repository.equals(repositories[i]))
return;
}
String results[] = new String[repositories.length + 1];
for (int i = 0; i < repositories.length; i++)
results[i] = repositories[i];
results[repositories.length] = repository;
repositories = results;
if (getState().isAvailable() && (classLoader != null)) {
classLoader.addRepository(repository);
if( loaderRepositories != null ) loaderRepositories.add(repository);
setClassPath();
}
}
/**
* 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 (container instanceof StandardContext) {
((StandardContext) container).reload();
}
} finally {
if (container.getLoader() != null) {
Thread.currentThread().setContextClassLoader
(container.getLoader().getClassLoader());
}
}
} else {
closeJARs(false);
}
}
/**
* Return the set of repositories defined for this class loader.
* If none are defined, a zero-length array is returned.
* For security reason, returns a clone of the Array (since
* String are immutable).
*/
@Override
public String[] findRepositories() {
return repositories.clone();
}
public String[] getRepositories() {
return repositories.clone();
}
/** Extra repositories for this loader
*/
public String getRepositoriesString() {
StringBuilder sb=new StringBuilder();
for( int i=0; i clazz = Class.forName(loaderClass);
WebappClassLoader classLoader = null;
if (parentClassLoader == null) {
parentClassLoader = container.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 (!(container instanceof Context))
return;
// Tell the class loader the root of the context
ServletContext servletContext =
((Context) container).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 (!(container instanceof Context))
return;
ServletContext servletContext =
((Context) container).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);
DirContext resources = container.getResources();
// Setting up the class repository (/WEB-INF/classes), if it exists
String classesPath = "/WEB-INF/classes";
DirContext classes = null;
try {
Object object = resources.lookup(classesPath);
if (object instanceof DirContext) {
classes = (DirContext) object;
}
} catch(NamingException e) {
// Silent catch: it's valid that no /WEB-INF/classes collection
// exists
}
if (classes != null) {
File classRepository = null;
String absoluteClassesPath =
servletContext.getRealPath(classesPath);
if (absoluteClassesPath != null) {
classRepository = new File(absoluteClassesPath);
} else {
classRepository = new File(workDir, classesPath);
if (!classRepository.isDirectory()) {
if (!classRepository.mkdirs())
throw new IOException(
sm.getString("webappLoader.mkdirFailure"));
}
if (!copyDir(classes, classRepository)) {
throw new IOException(
sm.getString("webappLoader.copyFailure"));
}
}
if(log.isDebugEnabled())
log.debug(sm.getString("webappLoader.classDeploy", classesPath,
classRepository.getAbsolutePath()));
// Adding the repository to the class loader
classLoader.addRepository(classesPath + "/", classRepository);
loaderRepositories.add(classesPath + "/" );
}
// Setting up the JAR repository (/WEB-INF/lib), if it exists
String libPath = "/WEB-INF/lib";
classLoader.setJarPath(libPath);
DirContext libDir = null;
// Looking up directory /WEB-INF/lib in the context
try {
Object object = resources.lookup(libPath);
if (object instanceof DirContext)
libDir = (DirContext) object;
} catch(NamingException e) {
// Silent catch: it's valid that no /WEB-INF/lib collection
// exists
}
if (libDir != null) {
boolean copyJars = false;
String absoluteLibPath = servletContext.getRealPath(libPath);
File destDir = null;
if (absoluteLibPath != null) {
destDir = new File(absoluteLibPath);
} else {
copyJars = true;
destDir = new File(workDir, libPath);
if (!destDir.isDirectory()) {
if (!destDir.mkdirs())
throw new IOException(
sm.getString("webappLoader.mkdirFailure"));
}
}
// Looking up directory /WEB-INF/lib in the context
NamingEnumeration enumeration = null;
try {
enumeration = libDir.list("");
} catch (NamingException e) {
IOException ioe = new IOException(sm.getString(
"webappLoader.namingFailure", libPath));
ioe.initCause(e);
throw ioe;
}
while (enumeration.hasMoreElements()) {
NameClassPair ncPair = enumeration.nextElement();
String filename = libPath + "/" + ncPair.getName();
if (!filename.endsWith(".jar"))
continue;
// 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, ncPair.getName());
if( log.isDebugEnabled())
log.debug(sm.getString("webappLoader.jarDeploy", filename,
destFile.getAbsolutePath()));
// Bug 45403 - Explicitly call lookup() on the name to check
// that the resource is readable. We cannot use resources
// returned by listBindings(), because that lists all of them,
// but does not perform the necessary checks on each.
Object obj = null;
try {
obj = libDir.lookup(ncPair.getName());
} catch (NamingException e) {
IOException ioe = new IOException(sm.getString(
"webappLoader.namingFailure", filename));
ioe.initCause(e);
throw ioe;
}
if (!(obj instanceof Resource))
continue;
Resource jarResource = (Resource) obj;
if (copyJars) {
if (!copy(jarResource.streamContent(),
new FileOutputStream(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 (!(container instanceof Context))
return;
ServletContext servletContext =
((Context) container).getServletContext();
if (servletContext == null)
return;
if (container instanceof StandardContext) {
String baseClasspath =
((StandardContext) container).getCompilerClasspath();
if (baseClasspath != null) {
servletContext.setAttribute(Globals.CLASS_PATH_ATTR,
baseClasspath);
return;
}
}
StringBuilder classpath = new StringBuilder();
// Assemble the class path information from our class loader chain
ClassLoader loader = getClassLoader();
int layers = 0;
int n = 0;
while (loader != null) {
if (!(loader instanceof URLClassLoader)) {
String cp=getClasspath( loader );
if( cp==null ) {
log.info( "Unknown loader " + loader + " " + loader.getClass());
} else {
if (n > 0)
classpath.append(File.pathSeparator);
classpath.append(cp);
n++;
}
break;
//continue;
}
URL repositories[] =
((URLClassLoader) loader).getURLs();
for (int i = 0; i < repositories.length; i++) {
String repository = repositories[i].toString();
if (repository.startsWith("file://"))
repository = repository.substring(7);
else if (repository.startsWith("file:"))
repository = repository.substring(5);
else if (repository.startsWith("jndi:"))
repository =
servletContext.getRealPath(repository.substring(5));
else
continue;
if (repository == null)
continue;
if (n > 0)
classpath.append(File.pathSeparator);
classpath.append(repository);
n++;
}
loader = loader.getParent();
layers++;
}
this.classpath=classpath.toString();
// Store the assembled class path as a servlet context attribute
servletContext.setAttribute(Globals.CLASS_PATH_ATTR,
classpath.toString());
}
// 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 ) {
if (log.isDebugEnabled())
log.debug("getClasspath ", ex);
}
return null;
}
/**
* Copy directory.
*/
private boolean copyDir(DirContext srcDir, File destDir) {
try {
NamingEnumeration enumeration = srcDir.list("");
while (enumeration.hasMoreElements()) {
NameClassPair ncPair = enumeration.nextElement();
String name = ncPair.getName();
Object object = srcDir.lookup(name);
File currentFile = new File(destDir, name);
if (object instanceof Resource) {
InputStream is = ((Resource) object).streamContent();
OutputStream os = new FileOutputStream(currentFile);
if (!copy(is, os))
return false;
} else if (object instanceof InputStream) {
OutputStream os = new FileOutputStream(currentFile);
if (!copy((InputStream) object, os))
return false;
} else if (object instanceof DirContext) {
if (!currentFile.isDirectory() && !currentFile.mkdir())
return false;
if (!copyDir((DirContext) object, currentFile))
return false;
}
}
} catch (NamingException e) {
return false;
} catch (IOException e) {
return false;
}
return true;
}
/**
* Copy a file to the specified temp directory. This is required only
* because Jasper depends on it.
*/
private boolean copy(InputStream is, OutputStream os) {
try {
byte[] buf = new byte[4096];
while (true) {
int len = is.read(buf);
if (len < 0)
break;
os.write(buf, 0, len);
}
is.close();
os.close();
} catch (IOException e) {
return false;
}
return true;
}
private static final org.apache.juli.logging.Log log=
org.apache.juli.logging.LogFactory.getLog( WebappLoader.class );
@Override
protected String getDomainInternal() {
return MBeanUtils.getDomain(container);
}
@Override
protected String getObjectNameKeyProperties() {
StringBuilder name = new StringBuilder("type=Loader");
if (container instanceof Context) {
name.append(",context=");
Context context = (Context) container;
String contextName = context.getName();
if (!contextName.startsWith("/")) {
name.append("/");
}
name.append(contextName);
name.append(",host=");
name.append(context.getParent().getName());
} else {
// Unlikely / impossible? Handle it to be safe
name.append(",container=");
name.append(container.getName());
}
return name.toString();
}
}