/*
* 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.compiler;
import java.io.InputStream;
import java.io.IOException;
import java.net.JarURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.net.URLConnection;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import org.xml.sax.InputSource;
import javax.servlet.ServletContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.jasper.Constants;
import org.apache.jasper.JasperException;
import org.apache.jasper.xmlparser.ParserUtils;
import org.apache.jasper.xmlparser.TreeNode;
/**
* A container for all tag libraries that are defined "globally"
* for the web application.
*
* Tag Libraries can be defined globally in one of two ways:
* 1. Via <taglib> elements in web.xml:
* the uri and location of the tag-library are specified in
* the <taglib> element.
* 2. Via packaged jar files that contain .tld files
* within the META-INF directory, or some subdirectory
* of it. The taglib is 'global' if it has the <uri>
* element defined.
*
* A mapping between the taglib URI and its associated TaglibraryInfoImpl
* is maintained in this container.
* Actually, that's what we'd like to do. However, because of the
* way the classes TagLibraryInfo and TagInfo have been defined,
* it is not currently possible to share an instance of TagLibraryInfo
* across page invocations. A bug has been submitted to the spec lead.
* In the mean time, all we do is save the 'location' where the
* TLD associated with a taglib URI can be found.
*
* When a JSP page has a taglib directive, the mappings in this container
* are first searched (see method getLocation()).
* If a mapping is found, then the location of the TLD is returned.
* If no mapping is found, then the uri specified
* in the taglib directive is to be interpreted as the location for
* the TLD of this tag library.
*
* @author Pierre Delisle
* @author Jan Luehe
*/
public class TldLocationsCache {
// Logger
private Log log = LogFactory.getLog(TldLocationsCache.class);
/**
* The types of URI one may specify for a tag library
*/
public static final int ABS_URI = 0;
public static final int ROOT_REL_URI = 1;
public static final int NOROOT_REL_URI = 2;
private static final String WEB_XML = "/WEB-INF/web.xml";
private static final String FILE_PROTOCOL = "file:";
private static final String JAR_FILE_SUFFIX = ".jar";
// Names of JARs that are known not to contain any TLDs
private static HashSet noTldJars;
/**
* The mapping of the 'global' tag library URI to the location (resource
* path) of the TLD associated with that tag library. The location is
* returned as a String array:
* [0] The location
* [1] If the location is a jar file, this is the location of the tld.
*/
private Hashtable mappings;
private boolean initialized;
private ServletContext ctxt;
private boolean redeployMode;
//*********************************************************************
// Constructor and Initilizations
/*
* Initializes the set of JARs that are known not to contain any TLDs
*/
static {
noTldJars = new HashSet();
noTldJars.add("ant.jar");
noTldJars.add("catalina.jar");
noTldJars.add("catalina-ant.jar");
noTldJars.add("catalina-cluster.jar");
noTldJars.add("catalina-optional.jar");
noTldJars.add("catalina-i18n-fr.jar");
noTldJars.add("catalina-i18n-ja.jar");
noTldJars.add("catalina-i18n-es.jar");
noTldJars.add("commons-dbcp.jar");
noTldJars.add("commons-modeler.jar");
noTldJars.add("commons-logging-api.jar");
noTldJars.add("commons-beanutils.jar");
noTldJars.add("commons-fileupload-1.0.jar");
noTldJars.add("commons-pool.jar");
noTldJars.add("commons-digester.jar");
noTldJars.add("commons-logging.jar");
noTldJars.add("commons-collections.jar");
noTldJars.add("commons-el.jar");
noTldJars.add("jakarta-regexp-1.2.jar");
noTldJars.add("jasper-compiler.jar");
noTldJars.add("jasper-runtime.jar");
noTldJars.add("jmx.jar");
noTldJars.add("jmx-tools.jar");
noTldJars.add("jsp-api.jar");
noTldJars.add("jkshm.jar");
noTldJars.add("jkconfig.jar");
noTldJars.add("naming-common.jar");
noTldJars.add("naming-resources.jar");
noTldJars.add("naming-factory.jar");
noTldJars.add("naming-java.jar");
noTldJars.add("servlet-api.jar");
noTldJars.add("servlets-default.jar");
noTldJars.add("servlets-invoker.jar");
noTldJars.add("servlets-common.jar");
noTldJars.add("servlets-webdav.jar");
noTldJars.add("tomcat-util.jar");
noTldJars.add("tomcat-http11.jar");
noTldJars.add("tomcat-jni.jar");
noTldJars.add("tomcat-jk.jar");
noTldJars.add("tomcat-jk2.jar");
noTldJars.add("tomcat-coyote.jar");
noTldJars.add("xercesImpl.jar");
noTldJars.add("xmlParserAPIs.jar");
noTldJars.add("xml-apis.jar");
// JARs from J2SE runtime
noTldJars.add("sunjce_provider.jar");
noTldJars.add("ldapsec.jar");
noTldJars.add("localedata.jar");
noTldJars.add("dnsns.jar");
}
public TldLocationsCache(ServletContext ctxt) {
this(ctxt, true);
}
/** Constructor.
*
* @param ctxt the servlet context of the web application in which Jasper
* is running
* @param redeployMode if true, then the compiler will allow redeploying
* a tag library from the same jar, at the expense of slowing down the
* server a bit. Note that this may only work on JDK 1.3.1_01a and later,
* because of JDK bug 4211817 fixed in this release.
* If redeployMode is false, a faster but less capable mode will be used.
*/
public TldLocationsCache(ServletContext ctxt, boolean redeployMode) {
this.ctxt = ctxt;
this.redeployMode = redeployMode;
mappings = new Hashtable();
initialized = false;
}
/**
* Sets the list of JARs that are known not to contain any TLDs.
*
* @param jarNames List of comma-separated names of JAR files that are
* known not to contain any TLDs
*/
public static void setNoTldJars(String jarNames) {
if (jarNames != null) {
noTldJars.clear();
StringTokenizer tokenizer = new StringTokenizer(jarNames, ",");
while (tokenizer.hasMoreElements()) {
noTldJars.add(tokenizer.nextToken());
}
}
}
/**
* Gets the 'location' of the TLD associated with the given taglib 'uri'.
*
* Returns null if the uri is not associated with any tag library 'exposed'
* in the web application. A tag library is 'exposed' either explicitly in
* web.xml or implicitly via the uri tag in the TLD of a taglib deployed
* in a jar file (WEB-INF/lib).
*
* @param uri The taglib uri
*
* @return An array of two Strings: The first element denotes the real
* path to the TLD. If the path to the TLD points to a jar file, then the
* second element denotes the name of the TLD entry in the jar file.
* Returns null if the uri is not associated with any tag library 'exposed'
* in the web application.
*/
public String[] getLocation(String uri) throws JasperException {
if (!initialized) {
init();
}
return (String[]) mappings.get(uri);
}
/**
* Returns the type of a URI:
* ABS_URI
* ROOT_REL_URI
* NOROOT_REL_URI
*/
public static int uriType(String uri) {
if (uri.indexOf(':') != -1) {
return ABS_URI;
} else if (uri.startsWith("/")) {
return ROOT_REL_URI;
} else {
return NOROOT_REL_URI;
}
}
private void init() throws JasperException {
if (initialized) return;
try {
processWebDotXml();
scanJars();
processTldsInFileSystem("/WEB-INF/");
initialized = true;
} catch (Exception ex) {
throw new JasperException(Localizer.getMessage(
"jsp.error.internal.tldinit", ex.getMessage()), ex);
}
}
/*
* Populates taglib map described in web.xml.
*/
private void processWebDotXml() throws Exception {
InputStream is = null;
try {
// Acquire input stream to web application deployment descriptor
String altDDName = (String)ctxt.getAttribute(
Constants.ALT_DD_ATTR);
URL uri = null;
if (altDDName != null) {
try {
uri = new URL(FILE_PROTOCOL+altDDName.replace('\\', '/'));
} catch (MalformedURLException e) {
if (log.isWarnEnabled()) {
log.warn(Localizer.getMessage(
"jsp.error.internal.filenotfound",
altDDName));
}
}
} else {
uri = ctxt.getResource(WEB_XML);
if (uri == null && log.isWarnEnabled()) {
log.warn(Localizer.getMessage(
"jsp.error.internal.filenotfound",
WEB_XML));
}
}
if (uri == null) {
return;
}
is = uri.openStream();
InputSource ip = new InputSource(is);
ip.setSystemId(uri.toExternalForm());
// Parse the web application deployment descriptor
TreeNode webtld = null;
// altDDName is the absolute path of the DD
if (altDDName != null) {
webtld = new ParserUtils().parseXMLDocument(altDDName, ip);
} else {
webtld = new ParserUtils().parseXMLDocument(WEB_XML, ip);
}
// Allow taglib to be an element of the root or jsp-config (JSP2.0)
TreeNode jspConfig = webtld.findChild("jsp-config");
if (jspConfig != null) {
webtld = jspConfig;
}
Iterator taglibs = webtld.findChildren("taglib");
while (taglibs.hasNext()) {
// Parse the next <taglib> element
TreeNode taglib = (TreeNode) taglibs.next();
String tagUri = null;
String tagLoc = null;
TreeNode child = taglib.findChild("taglib-uri");
if (child != null)
tagUri = child.getBody();
child = taglib.findChild("taglib-location");
if (child != null)
tagLoc = child.getBody();
// Save this location if appropriate
if (tagLoc == null)
continue;
if (uriType(tagLoc) == NOROOT_REL_URI)
tagLoc = "/WEB-INF/" + tagLoc;
String tagLoc2 = null;
if (tagLoc.endsWith(JAR_FILE_SUFFIX)) {
tagLoc = ctxt.getResource(tagLoc).toString();
tagLoc2 = "META-INF/taglib.tld";
}
mappings.put(tagUri, new String[] { tagLoc, tagLoc2 });
}
} finally {
if (is != null) {
try {
is.close();
} catch (Throwable t) {}
}
}
}
/**
* Scans the given JarURLConnection for TLD files located in META-INF
* (or a subdirectory of it), adding an implicit map entry to the taglib
* map for any TLD that has a <uri> element.
*
* @param conn The JarURLConnection to the JAR file to scan
* @param ignore true if any exceptions raised when processing the given
* JAR should be ignored, false otherwise
*/
private void scanJar(JarURLConnection conn, boolean ignore)
throws JasperException {
JarFile jarFile = null;
String resourcePath = conn.getJarFileURL().toString();
try {
if (redeployMode) {
conn.setUseCaches(false);
}
jarFile = conn.getJarFile();
Enumeration entries = jarFile.entries();
while (entries.hasMoreElements()) {
JarEntry entry = (JarEntry) entries.nextElement();
String name = entry.getName();
if (!name.startsWith("META-INF/")) continue;
if (!name.endsWith(".tld")) continue;
InputStream stream = jarFile.getInputStream(entry);
try {
String uri = getUriFromTld(resourcePath, stream);
// Add implicit map entry only if its uri is not already
// present in the map
if (uri != null && mappings.get(uri) == null) {
mappings.put(uri, new String[]{ resourcePath, name });
}
} finally {
if (stream != null) {
try {
stream.close();
} catch (Throwable t) {
// do nothing
}
}
}
}
} catch (Exception ex) {
if (!redeployMode) {
// if not in redeploy mode, close the jar in case of an error
if (jarFile != null) {
try {
jarFile.close();
} catch (Throwable t) {
// ignore
}
}
}
if (!ignore) {
throw new JasperException(ex);
}
} finally {
if (redeployMode) {
// if in redeploy mode, always close the jar
if (jarFile != null) {
try {
jarFile.close();
} catch (Throwable t) {
// ignore
}
}
}
}
}
/*
* Searches the filesystem under /WEB-INF for any TLD files, and adds
* an implicit map entry to the taglib map for any TLD that has a <uri>
* element.
*/
private void processTldsInFileSystem(String startPath)
throws Exception {
Set dirList = ctxt.getResourcePaths(startPath);
if (dirList != null) {
Iterator it = dirList.iterator();
while (it.hasNext()) {
String path = (String) it.next();
if (path.endsWith("/")) {
processTldsInFileSystem(path);
}
if (!path.endsWith(".tld")) {
continue;
}
InputStream stream = ctxt.getResourceAsStream(path);
String uri = null;
try {
uri = getUriFromTld(path, stream);
} finally {
if (stream != null) {
try {
stream.close();
} catch (Throwable t) {
// do nothing
}
}
}
// Add implicit map entry only if its uri is not already
// present in the map
if (uri != null && mappings.get(uri) == null) {
mappings.put(uri, new String[] { path, null });
}
}
}
}
/*
* Returns the value of the uri element of the given TLD, or null if the
* given TLD does not contain any such element.
*/
private String getUriFromTld(String resourcePath, InputStream in)
throws JasperException
{
// Parse the tag library descriptor at the specified resource path
TreeNode tld = new ParserUtils().parseXMLDocument(resourcePath, in);
TreeNode uri = tld.findChild("uri");
if (uri != null) {
String body = uri.getBody();
if (body != null)
return body;
}
return null;
}
/*
* Scans all JARs accessible to the webapp's classloader and its
* parent classloaders for TLDs.
*
* The list of JARs always includes the JARs under WEB-INF/lib, as well as
* all shared JARs in the classloader delegation chain of the webapp's
* classloader.
*
* Considering JARs in the classloader delegation chain constitutes a
* Tomcat-specific extension to the TLD search
* order defined in the JSP spec. It allows tag libraries packaged as JAR
* files to be shared by web applications by simply dropping them in a
* location that all web applications have access to (e.g.,
* <CATALINA_HOME>/common/lib).
*
* The set of shared JARs to be scanned for TLDs is narrowed down by
* the <tt>noTldJars</tt> class variable, which contains the names of JARs
* that are known not to contain any TLDs.
*/
private void scanJars() throws Exception {
ClassLoader webappLoader
= Thread.currentThread().getContextClassLoader();
ClassLoader loader = webappLoader;
while (loader != null) {
if (loader instanceof URLClassLoader) {
URL[] urls = ((URLClassLoader) loader).getURLs();
for (int i=0; i<urls.length; i++) {
URLConnection conn = urls[i].openConnection();
if (conn instanceof JarURLConnection) {
if (needScanJar(loader, webappLoader,
((JarURLConnection) conn).getJarFile().getName())) {
scanJar((JarURLConnection) conn, true);
}
} else {
String urlStr = urls[i].toString();
if (urlStr.startsWith(FILE_PROTOCOL)
&& urlStr.endsWith(JAR_FILE_SUFFIX)
&& needScanJar(loader, webappLoader, urlStr)) {
URL jarURL = new URL("jar:" + urlStr + "!/");
scanJar((JarURLConnection) jarURL.openConnection(),
true);
}
}
}
}
loader = loader.getParent();
}
}
/*
* Determines if the JAR file with the given <tt>jarPath</tt> needs to be
* scanned for TLDs.
*
* @param loader The current classloader in the parent chain
* @param webappLoader The webapp classloader
* @param jarPath The JAR file path
*
* @return TRUE if the JAR file identified by <tt>jarPath</tt> needs to be
* scanned for TLDs, FALSE otherwise
*/
private boolean needScanJar(ClassLoader loader, ClassLoader webappLoader,
String jarPath) {
if (loader == webappLoader) {
// JARs under WEB-INF/lib must be scanned unconditionally according
// to the spec.
return true;
} else {
String jarName = jarPath;
int slash = jarPath.lastIndexOf('/');
if (slash >= 0) {
jarName = jarPath.substring(slash + 1);
}
return (!noTldJars.contains(jarName));
}
}
}