Source Code Cross Referenced for StandardClassLoader.java in  » Sevlet-Container » tomcat-catalina » org » apache » catalina » loader » Java Source Code / Java DocumentationJava Source Code and Java Documentation

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Java Source Code / Java Documentation » Sevlet Container » tomcat catalina » org.apache.catalina.loader 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


0001:        /*
0002:         * Copyright 1999,2004 The Apache Software Foundation.
0003:         * 
0004:         * Licensed under the Apache License, Version 2.0 (the "License");
0005:         * you may not use this file except in compliance with the License.
0006:         * You may obtain a copy of the License at
0007:         * 
0008:         *      http://www.apache.org/licenses/LICENSE-2.0
0009:         * 
0010:         * Unless required by applicable law or agreed to in writing, software
0011:         * distributed under the License is distributed on an "AS IS" BASIS,
0012:         * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
0013:         * See the License for the specific language governing permissions and
0014:         * limitations under the License.
0015:         */
0016:
0017:        package org.apache.catalina.loader;
0018:
0019:        import java.io.File;
0020:        import java.io.FilePermission;
0021:        import java.io.IOException;
0022:        import java.io.InputStream;
0023:        import java.net.JarURLConnection;
0024:        import java.net.MalformedURLException;
0025:        import java.net.URL;
0026:        import java.net.URLClassLoader;
0027:        import java.net.URLConnection;
0028:        import java.net.URLStreamHandler;
0029:        import java.net.URLStreamHandlerFactory;
0030:        import java.security.AccessControlException;
0031:        import java.security.CodeSource;
0032:        import java.security.Permission;
0033:        import java.security.PermissionCollection;
0034:        import java.security.Policy;
0035:        import java.util.ArrayList;
0036:        import java.util.Enumeration;
0037:        import java.util.HashMap;
0038:        import java.util.Iterator;
0039:        import java.util.jar.JarFile;
0040:        import java.util.jar.JarInputStream;
0041:        import java.util.jar.Manifest;
0042:
0043:        import org.apache.naming.JndiPermission;
0044:        import org.apache.tomcat.util.compat.JdkCompat;
0045:
0046:        /**
0047:         * Subclass implementation of <b>java.net.URLClassLoader</b> that knows how
0048:         * to load classes from disk directories, as well as local and remote JAR
0049:         * files.  It also implements the <code>Reloader</code> interface, to provide
0050:         * automatic reloading support to the associated loader.
0051:         * <p>
0052:         * In all cases, URLs must conform to the contract specified by
0053:         * <code>URLClassLoader</code> - any URL that ends with a "/" character is
0054:         * assumed to represent a directory; all other URLs are assumed to be the
0055:         * address of a JAR file.
0056:         * <p>
0057:         * <strong>IMPLEMENTATION NOTE</strong> - Local repositories are searched in
0058:         * the order they are added via the initial constructor and/or any subsequent
0059:         * calls to <code>addRepository()</code>.
0060:         * <p>
0061:         * <strong>IMPLEMENTATION NOTE</strong> - At present, there are no dependencies
0062:         * from this class to any other Catalina class, so that it could be used
0063:         * independently.
0064:         *
0065:         * @author Craig R. McClanahan
0066:         * @author Remy Maucherat
0067:         * @version $Revision: 1.13 $ $Date: 2004/05/26 15:47:34 $
0068:         */
0069:
0070:        public class StandardClassLoader extends URLClassLoader implements 
0071:                Reloader, StandardClassLoaderMBean {
0072:
0073:            // ----------------------------------------------------------- Constructors
0074:
0075:            /**
0076:             * Construct a new ClassLoader with no defined repositories and no
0077:             * parent ClassLoader.
0078:             */
0079:            public StandardClassLoader() {
0080:
0081:                super (new URL[0]);
0082:                this .parent = getParent();
0083:                this .system = getSystemClassLoader();
0084:                securityManager = System.getSecurityManager();
0085:
0086:            }
0087:
0088:            /**
0089:             * Construct a new ClassLoader with no defined repositories and no
0090:             * parent ClassLoader, but with a stream handler factory.
0091:             *
0092:             * @param factory the URLStreamHandlerFactory to use when creating URLs
0093:             */
0094:            public StandardClassLoader(URLStreamHandlerFactory factory) {
0095:
0096:                super (new URL[0], null, factory);
0097:                this .factory = factory;
0098:
0099:            }
0100:
0101:            /**
0102:             * Construct a new ClassLoader with no defined repositories and the
0103:             * specified parent ClassLoader.
0104:             *
0105:             * @param parent The parent ClassLoader
0106:             */
0107:            public StandardClassLoader(ClassLoader parent) {
0108:
0109:                super ((new URL[0]), parent);
0110:                this .parent = parent;
0111:                this .system = getSystemClassLoader();
0112:                securityManager = System.getSecurityManager();
0113:
0114:            }
0115:
0116:            /**
0117:             * Construct a new ClassLoader with no defined repositories and the
0118:             * specified parent ClassLoader.
0119:             *
0120:             * @param parent The parent ClassLoader
0121:             * @param factory the URLStreamHandlerFactory to use when creating URLs
0122:             */
0123:            public StandardClassLoader(ClassLoader parent,
0124:                    URLStreamHandlerFactory factory) {
0125:
0126:                super ((new URL[0]), parent, factory);
0127:                this .factory = factory;
0128:
0129:            }
0130:
0131:            /**
0132:             * Construct a new ClassLoader with the specified repositories and
0133:             * no parent ClassLoader.
0134:             *
0135:             * @param repositories The initial set of repositories
0136:             */
0137:            public StandardClassLoader(String repositories[]) {
0138:
0139:                super (convert(repositories));
0140:                this .parent = getParent();
0141:                this .system = getSystemClassLoader();
0142:                securityManager = System.getSecurityManager();
0143:                if (repositories != null) {
0144:                    for (int i = 0; i < repositories.length; i++)
0145:                        addRepositoryInternal(repositories[i]);
0146:                }
0147:
0148:            }
0149:
0150:            /**
0151:             * Construct a new ClassLoader with the specified repositories and
0152:             * parent ClassLoader.
0153:             *
0154:             * @param repositories The initial set of repositories
0155:             * @param parent The parent ClassLoader
0156:             */
0157:            public StandardClassLoader(String repositories[], ClassLoader parent) {
0158:
0159:                super (convert(repositories), parent);
0160:                this .parent = parent;
0161:                this .system = getSystemClassLoader();
0162:                securityManager = System.getSecurityManager();
0163:                if (repositories != null) {
0164:                    for (int i = 0; i < repositories.length; i++)
0165:                        addRepositoryInternal(repositories[i]);
0166:                }
0167:
0168:            }
0169:
0170:            /**
0171:             * Construct a new ClassLoader with the specified repositories and
0172:             * parent ClassLoader.
0173:             *
0174:             * @param repositories The initial set of repositories
0175:             * @param parent The parent ClassLoader
0176:             */
0177:            public StandardClassLoader(URL repositories[], ClassLoader parent) {
0178:
0179:                super (repositories, parent);
0180:                this .parent = parent;
0181:                this .system = getSystemClassLoader();
0182:                securityManager = System.getSecurityManager();
0183:                if (repositories != null) {
0184:                    for (int i = 0; i < repositories.length; i++)
0185:                        addRepositoryInternal(repositories[i].toString());
0186:                }
0187:
0188:            }
0189:
0190:            // ----------------------------------------------------- Class Variables
0191:
0192:            /**
0193:             * JDK compatibility support
0194:             */
0195:            private static final JdkCompat jdkCompat = JdkCompat.getJdkCompat();
0196:
0197:            // ----------------------------------------------------- Instance Variables
0198:
0199:            /**
0200:             * The debugging detail level of this component.
0201:             */
0202:            protected int debug = 0;
0203:
0204:            /**
0205:             * Should this class loader delegate to the parent class loader
0206:             * <strong>before</strong> searching its own repositories (i.e. the
0207:             * usual Java2 delegation model)?  If set to <code>false</code>,
0208:             * this class loader will search its own repositories first, and
0209:             * delegate to the parent only if the class or resource is not
0210:             * found locally.
0211:             */
0212:            protected boolean delegate = false;
0213:
0214:            /**
0215:             * The list of local repositories, in the order they should be searched
0216:             * for locally loaded classes or resources.
0217:             */
0218:            protected String repositories[] = new String[0];
0219:
0220:            /**
0221:             * A list of read File and Jndi Permission's required if this loader
0222:             * is for a web application context.
0223:             */
0224:            private ArrayList permissionList = new ArrayList();
0225:
0226:            /**
0227:             * The PermissionCollection for each CodeSource for a web
0228:             * application context.
0229:             */
0230:            private HashMap loaderPC = new HashMap();
0231:
0232:            /**
0233:             * Instance of the SecurityManager installed.
0234:             */
0235:            private SecurityManager securityManager = null;
0236:
0237:            /**
0238:             * Flag that the security policy has been refreshed from file.
0239:             */
0240:            private boolean policy_refresh = false;
0241:
0242:            /**
0243:             * The parent class loader.
0244:             */
0245:            private ClassLoader parent = null;
0246:
0247:            /**
0248:             * The system class loader.
0249:             */
0250:            private ClassLoader system = null;
0251:
0252:            /**
0253:             * URL stream handler for additional protocols.
0254:             */
0255:            protected URLStreamHandlerFactory factory = null;
0256:
0257:            // ------------------------------------------------------------- Properties
0258:
0259:            /**
0260:             * Return the debugging detail level for this component.
0261:             */
0262:            public int getDebug() {
0263:
0264:                return (this .debug);
0265:
0266:            }
0267:
0268:            /**
0269:             * Set the debugging detail level for this component.
0270:             *
0271:             * @param debug The new debugging detail level
0272:             */
0273:            public void setDebug(int debug) {
0274:
0275:                this .debug = debug;
0276:
0277:            }
0278:
0279:            /**
0280:             * Return the "delegate first" flag for this class loader.
0281:             */
0282:            public boolean getDelegate() {
0283:
0284:                return (this .delegate);
0285:
0286:            }
0287:
0288:            /**
0289:             * Set the "delegate first" flag for this class loader.
0290:             *
0291:             * @param delegate The new "delegate first" flag
0292:             */
0293:            public void setDelegate(boolean delegate) {
0294:
0295:                this .delegate = delegate;
0296:
0297:            }
0298:
0299:            /**
0300:             * If there is a Java SecurityManager create a read FilePermission
0301:             * or JndiPermission for the file directory path.
0302:             *
0303:             * @param path file directory path
0304:             */
0305:            protected void setPermissions(String path) {
0306:                if (securityManager != null) {
0307:                    if (path.startsWith("jndi:")
0308:                            || path.startsWith("jar:jndi:")) {
0309:                        permissionList.add(new JndiPermission(path + "*"));
0310:                    } else {
0311:                        permissionList.add(new FilePermission(path + "-",
0312:                                "read"));
0313:                    }
0314:                }
0315:            }
0316:
0317:            /**
0318:             * If there is a Java SecurityManager add a read FilePermission
0319:             * or JndiPermission for URL.
0320:             *
0321:             * @param url URL for a file or directory on local system
0322:             */
0323:            protected void setPermissions(URL url) {
0324:                setPermissions(url.toString());
0325:            }
0326:
0327:            // ------------------------------------------------------- Reloader Methods
0328:
0329:            /**
0330:             * Add a new repository to the set of places this ClassLoader can look for
0331:             * classes to be loaded.
0332:             *
0333:             * @param repository Name of a source of classes to be loaded, such as a
0334:             *  directory pathname, a JAR file pathname, or a ZIP file pathname
0335:             *
0336:             * @exception IllegalArgumentException if the specified repository is
0337:             *  invalid or does not exist
0338:             */
0339:            public void addRepository(String repository) {
0340:
0341:                if (debug >= 1)
0342:                    log("addRepository(" + repository + ")");
0343:
0344:                // Add this repository to our underlying class loader
0345:                try {
0346:                    URLStreamHandler streamHandler = null;
0347:                    String protocol = parseProtocol(repository);
0348:                    if (factory != null)
0349:                        streamHandler = factory
0350:                                .createURLStreamHandler(protocol);
0351:                    URL url = new URL(null, repository, streamHandler);
0352:                    super .addURL(url);
0353:                } catch (MalformedURLException e) {
0354:                    IllegalArgumentException iae = new IllegalArgumentException(
0355:                            "Invalid repository: " + repository);
0356:                    jdkCompat.chainException(iae, e);
0357:                    throw iae;
0358:                }
0359:
0360:                // Add this repository to our internal list
0361:                addRepositoryInternal(repository);
0362:
0363:            }
0364:
0365:            /**
0366:             * Return a String array of the current repositories for this class
0367:             * loader.  If there are no repositories, a zero-length array is
0368:             * returned. For security reason, returns a clone of the Array (since 
0369:             * String are immutable).
0370:             */
0371:            public String[] findRepositories() {
0372:
0373:                return ((String[]) repositories.clone());
0374:
0375:            }
0376:
0377:            /**
0378:             * This class loader doesn't check for reloading.
0379:             */
0380:            public boolean modified() {
0381:
0382:                return (false);
0383:
0384:            }
0385:
0386:            /**
0387:             * Render a String representation of this object.
0388:             */
0389:            public String toString() {
0390:
0391:                StringBuffer sb = new StringBuffer("StandardClassLoader\r\n");
0392:                sb.append("  delegate: ");
0393:                sb.append(delegate);
0394:                sb.append("\r\n");
0395:                sb.append("  repositories:\r\n");
0396:                for (int i = 0; i < repositories.length; i++) {
0397:                    sb.append("    ");
0398:                    sb.append(repositories[i]);
0399:                    sb.append("\r\n");
0400:                }
0401:                if (this .parent != null) {
0402:                    sb.append("----------> Parent Classloader:\r\n");
0403:                    sb.append(this .parent.toString());
0404:                    sb.append("\r\n");
0405:                }
0406:                return (sb.toString());
0407:
0408:            }
0409:
0410:            // ---------------------------------------------------- ClassLoader Methods
0411:
0412:            /**
0413:             * Find the specified class in our local repositories, if possible.  If
0414:             * not found, throw <code>ClassNotFoundException</code>.
0415:             *
0416:             * @param name Name of the class to be loaded
0417:             *
0418:             * @exception ClassNotFoundException if the class was not found
0419:             */
0420:            public Class findClass(String name) throws ClassNotFoundException {
0421:
0422:                if (debug >= 3)
0423:                    log("    findClass(" + name + ")");
0424:
0425:                // (1) Permission to define this class when using a SecurityManager
0426:                if (securityManager != null) {
0427:                    int i = name.lastIndexOf('.');
0428:                    if (i >= 0) {
0429:                        try {
0430:                            if (debug >= 4)
0431:                                log("      securityManager.checkPackageDefinition");
0432:                            securityManager.checkPackageDefinition(name
0433:                                    .substring(0, i));
0434:                        } catch (Exception se) {
0435:                            if (debug >= 4)
0436:                                log(
0437:                                        "      -->Exception-->ClassNotFoundException",
0438:                                        se);
0439:                            throw new ClassNotFoundException(name, se);
0440:                        }
0441:                    }
0442:                }
0443:
0444:                // Ask our superclass to locate this class, if possible
0445:                // (throws ClassNotFoundException if it is not found)
0446:                Class clazz = null;
0447:                try {
0448:                    if (debug >= 4)
0449:                        log("      super.findClass(" + name + ")");
0450:                    try {
0451:                        synchronized (this ) {
0452:                            clazz = findLoadedClass(name);
0453:                            if (clazz != null)
0454:                                return clazz;
0455:                            clazz = super .findClass(name);
0456:                        }
0457:                    } catch (AccessControlException ace) {
0458:                        throw new ClassNotFoundException(name, ace);
0459:                    } catch (RuntimeException e) {
0460:                        if (debug >= 4)
0461:                            log("      -->RuntimeException Rethrown", e);
0462:                        throw e;
0463:                    }
0464:                    if (clazz == null) {
0465:                        if (debug >= 3)
0466:                            log("    --> Returning ClassNotFoundException");
0467:                        throw new ClassNotFoundException(name);
0468:                    }
0469:                } catch (ClassNotFoundException e) {
0470:                    if (debug >= 3)
0471:                        log("    --> Passing on ClassNotFoundException", e);
0472:                    throw e;
0473:                }
0474:
0475:                // Return the class we have located
0476:                if (debug >= 4)
0477:                    log("      Returning class " + clazz);
0478:                if ((debug >= 4) && (clazz != null))
0479:                    log("      Loaded by " + clazz.getClassLoader());
0480:                return (clazz);
0481:
0482:            }
0483:
0484:            /**
0485:             * Find the specified resource in our local repository, and return a
0486:             * <code>URL</code> refering to it, or <code>null</code> if this resource
0487:             * cannot be found.
0488:             *
0489:             * @param name Name of the resource to be found
0490:             */
0491:            public URL findResource(String name) {
0492:
0493:                if (debug >= 3)
0494:                    log("    findResource(" + name + ")");
0495:
0496:                URL url = super .findResource(name);
0497:                if (debug >= 3) {
0498:                    if (url != null)
0499:                        log("    --> Returning '" + url.toString() + "'");
0500:                    else
0501:                        log("    --> Resource not found, returning null");
0502:                }
0503:                return (url);
0504:
0505:            }
0506:
0507:            /**
0508:             * Return an enumeration of <code>URLs</code> representing all of the
0509:             * resources with the given name.  If no resources with this name are
0510:             * found, return an empty enumeration.
0511:             *
0512:             * @param name Name of the resources to be found
0513:             *
0514:             * @exception IOException if an input/output error occurs
0515:             */
0516:            public Enumeration findResources(String name) throws IOException {
0517:
0518:                if (debug >= 3)
0519:                    log("    findResources(" + name + ")");
0520:                return (super .findResources(name));
0521:
0522:            }
0523:
0524:            /**
0525:             * Find the resource with the given name.  A resource is some data
0526:             * (images, audio, text, etc.) that can be accessed by class code in a
0527:             * way that is independent of the location of the code.  The name of a
0528:             * resource is a "/"-separated path name that identifies the resource.
0529:             * If the resource cannot be found, return <code>null</code>.
0530:             * <p>
0531:             * This method searches according to the following algorithm, returning
0532:             * as soon as it finds the appropriate URL.  If the resource cannot be
0533:             * found, returns <code>null</code>.
0534:             * <ul>
0535:             * <li>If the <code>delegate</code> property is set to <code>true</code>,
0536:             *     call the <code>getResource()</code> method of the parent class
0537:             *     loader, if any.</li>
0538:             * <li>Call <code>findResource()</code> to find this resource in our
0539:             *     locally defined repositories.</li>
0540:             * <li>Call the <code>getResource()</code> method of the parent class
0541:             *     loader, if any.</li>
0542:             * </ul>
0543:             *
0544:             * @param name Name of the resource to return a URL for
0545:             */
0546:            public URL getResource(String name) {
0547:
0548:                if (debug >= 2)
0549:                    log("getResource(" + name + ")");
0550:                URL url = null;
0551:
0552:                // (1) Delegate to parent if requested
0553:                if (delegate) {
0554:                    if (debug >= 3)
0555:                        log("  Delegating to parent classloader");
0556:                    ClassLoader loader = parent;
0557:                    if (loader == null)
0558:                        loader = system;
0559:                    url = loader.getResource(name);
0560:                    if (url != null) {
0561:                        if (debug >= 2)
0562:                            log("  --> Returning '" + url.toString() + "'");
0563:                        return (url);
0564:                    }
0565:                }
0566:
0567:                // (2) Search local repositories
0568:                if (debug >= 3)
0569:                    log("  Searching local repositories");
0570:                url = findResource(name);
0571:                if (url != null) {
0572:                    if (debug >= 2)
0573:                        log("  --> Returning '" + url.toString() + "'");
0574:                    return (url);
0575:                }
0576:
0577:                // (3) Delegate to parent unconditionally if not already attempted
0578:                if (!delegate) {
0579:                    ClassLoader loader = parent;
0580:                    if (loader == null)
0581:                        loader = system;
0582:                    url = loader.getResource(name);
0583:                    if (url != null) {
0584:                        if (debug >= 2)
0585:                            log("  --> Returning '" + url.toString() + "'");
0586:                        return (url);
0587:                    }
0588:                }
0589:
0590:                // (4) Resource was not found
0591:                if (debug >= 2)
0592:                    log("  --> Resource not found, returning null");
0593:                return (null);
0594:
0595:            }
0596:
0597:            /**
0598:             * Find the resource with the given name, and return an input stream
0599:             * that can be used for reading it.  The search order is as described
0600:             * for <code>getResource()</code>, after checking to see if the resource
0601:             * data has been previously cached.  If the resource cannot be found,
0602:             * return <code>null</code>.
0603:             *
0604:             * @param name Name of the resource to return an input stream for
0605:             */
0606:            public InputStream getResourceAsStream(String name) {
0607:
0608:                if (debug >= 2)
0609:                    log("getResourceAsStream(" + name + ")");
0610:                InputStream stream = null;
0611:
0612:                // (0) Check for a cached copy of this resource
0613:                stream = findLoadedResource(name);
0614:                if (stream != null) {
0615:                    if (debug >= 2)
0616:                        log("  --> Returning stream from cache");
0617:                    return (stream);
0618:                }
0619:
0620:                // (1) Delegate to parent if requested
0621:                if (delegate) {
0622:                    if (debug >= 3)
0623:                        log("  Delegating to parent classloader");
0624:                    ClassLoader loader = parent;
0625:                    if (loader == null)
0626:                        loader = system;
0627:                    stream = loader.getResourceAsStream(name);
0628:                    if (stream != null) {
0629:                        // FIXME - cache???
0630:                        if (debug >= 2)
0631:                            log("  --> Returning stream from parent");
0632:                        return (stream);
0633:                    }
0634:                }
0635:
0636:                // (2) Search local repositories
0637:                if (debug >= 3)
0638:                    log("  Searching local repositories");
0639:                URL url = findResource(name);
0640:                if (url != null) {
0641:                    // FIXME - cache???
0642:                    if (debug >= 2)
0643:                        log("  --> Returning stream from local");
0644:                    try {
0645:                        return (url.openStream());
0646:                    } catch (IOException e) {
0647:                        log("url.openStream(" + url.toString() + ")", e);
0648:                        return (null);
0649:                    }
0650:                }
0651:
0652:                // (3) Delegate to parent unconditionally
0653:                if (!delegate) {
0654:                    if (debug >= 3)
0655:                        log("  Delegating to parent classloader");
0656:                    ClassLoader loader = parent;
0657:                    if (loader == null)
0658:                        loader = system;
0659:                    stream = loader.getResourceAsStream(name);
0660:                    if (stream != null) {
0661:                        // FIXME - cache???
0662:                        if (debug >= 2)
0663:                            log("  --> Returning stream from parent");
0664:                        return (stream);
0665:                    }
0666:                }
0667:
0668:                // (4) Resource was not found
0669:                if (debug >= 2)
0670:                    log("  --> Resource not found, returning null");
0671:                return (null);
0672:
0673:            }
0674:
0675:            /**
0676:             * Load the class with the specified name.  This method searches for
0677:             * classes in the same manner as <code>loadClass(String, boolean)</code>
0678:             * with <code>false</code> as the second argument.
0679:             *
0680:             * @param name Name of the class to be loaded
0681:             *
0682:             * @exception ClassNotFoundException if the class was not found
0683:             */
0684:            public Class loadClass(String name) throws ClassNotFoundException {
0685:
0686:                return (loadClass(name, false));
0687:
0688:            }
0689:
0690:            /**
0691:             * Load the class with the specified name, searching using the following
0692:             * algorithm until it finds and returns the class.  If the class cannot
0693:             * be found, returns <code>ClassNotFoundException</code>.
0694:             * <ul>
0695:             * <li>Call <code>findLoadedClass(String)</code> to check if the
0696:             *     class has already been loaded.  If it has, the same
0697:             *     <code>Class</code> object is returned.</li>
0698:             * <li>If the <code>delegate</code> property is set to <code>true</code>,
0699:             *     call the <code>loadClass()</code> method of the parent class
0700:             *     loader, if any.</li>
0701:             * <li>Call <code>findClass()</code> to find this class in our locally
0702:             *     defined repositories.</li>
0703:             * <li>Call the <code>loadClass()</code> method of our parent
0704:             *     class loader, if any.</li>
0705:             * </ul>
0706:             * If the class was found using the above steps, and the
0707:             * <code>resolve</code> flag is <code>true</code>, this method will then
0708:             * call <code>resolveClass(Class)</code> on the resulting Class object.
0709:             *
0710:             * @param name Name of the class to be loaded
0711:             * @param resolve If <code>true</code> then resolve the class
0712:             *
0713:             * @exception ClassNotFoundException if the class was not found
0714:             */
0715:            public Class loadClass(String name, boolean resolve)
0716:                    throws ClassNotFoundException {
0717:
0718:                if (debug >= 2)
0719:                    log("loadClass(" + name + ", " + resolve + ")");
0720:                Class clazz = null;
0721:
0722:                // (0) Check our previously loaded class cache
0723:                clazz = findLoadedClass(name);
0724:                if (clazz != null) {
0725:                    if (debug >= 3)
0726:                        log("  Returning class from cache");
0727:                    if (resolve)
0728:                        resolveClass(clazz);
0729:                    return (clazz);
0730:                }
0731:
0732:                // If a system class, use system class loader
0733:                if (name.startsWith("java.")) {
0734:                    ClassLoader loader = system;
0735:                    clazz = loader.loadClass(name);
0736:                    if (clazz != null) {
0737:                        if (resolve)
0738:                            resolveClass(clazz);
0739:                        return (clazz);
0740:                    }
0741:                    throw new ClassNotFoundException(name);
0742:                }
0743:
0744:                // (.5) Permission to access this class when using a SecurityManager
0745:                if (securityManager != null) {
0746:                    int i = name.lastIndexOf('.');
0747:                    if (i >= 0) {
0748:                        try {
0749:                            securityManager.checkPackageAccess(name.substring(
0750:                                    0, i));
0751:                        } catch (SecurityException se) {
0752:                            String error = "Security Violation, attempt to use "
0753:                                    + "Restricted Class: " + name;
0754:                            log(error);
0755:                            throw new ClassNotFoundException(error, se);
0756:                        }
0757:                    }
0758:                }
0759:
0760:                // (1) Delegate to our parent if requested
0761:                if (delegate) {
0762:                    if (debug >= 3)
0763:                        log("  Delegating to parent classloader");
0764:                    ClassLoader loader = parent;
0765:                    if (loader == null)
0766:                        loader = system;
0767:                    try {
0768:                        clazz = loader.loadClass(name);
0769:                        if (clazz != null) {
0770:                            if (debug >= 3)
0771:                                log("  Loading class from parent");
0772:                            if (resolve)
0773:                                resolveClass(clazz);
0774:                            return (clazz);
0775:                        }
0776:                    } catch (ClassNotFoundException e) {
0777:                        ;
0778:                    }
0779:                }
0780:
0781:                // (2) Search local repositories
0782:                if (debug >= 3)
0783:                    log("  Searching local repositories");
0784:                try {
0785:                    clazz = findClass(name);
0786:                    if (clazz != null) {
0787:                        if (debug >= 3)
0788:                            log("  Loading class from local repository");
0789:                        if (resolve)
0790:                            resolveClass(clazz);
0791:                        return (clazz);
0792:                    }
0793:                } catch (ClassNotFoundException e) {
0794:                    ;
0795:                }
0796:
0797:                // (3) Delegate to parent unconditionally
0798:                if (!delegate) {
0799:                    if (debug >= 3)
0800:                        log("  Delegating to parent classloader");
0801:                    ClassLoader loader = parent;
0802:                    if (loader == null)
0803:                        loader = system;
0804:                    try {
0805:                        clazz = loader.loadClass(name);
0806:                        if (clazz != null) {
0807:                            if (debug >= 3)
0808:                                log("  Loading class from parent");
0809:                            if (resolve)
0810:                                resolveClass(clazz);
0811:                            return (clazz);
0812:                        }
0813:                    } catch (ClassNotFoundException e) {
0814:                        ;
0815:                    }
0816:                }
0817:
0818:                // This class was not found
0819:                throw new ClassNotFoundException(name);
0820:
0821:            }
0822:
0823:            /**
0824:             * Get the Permissions for a CodeSource.  If this instance
0825:             * of StandardClassLoader is for a web application context,
0826:             * add read FilePermissions for the base directory (if unpacked),
0827:             * the context URL, and jar file resources.
0828:             *
0829:             * @param codeSource where the code was loaded from
0830:             * @return PermissionCollection for CodeSource
0831:             */
0832:            protected final PermissionCollection getPermissions(
0833:                    CodeSource codeSource) {
0834:                if (!policy_refresh) {
0835:                    // Refresh the security policies
0836:                    Policy policy = Policy.getPolicy();
0837:                    policy.refresh();
0838:                    policy_refresh = true;
0839:                }
0840:                String codeUrl = codeSource.getLocation().toString();
0841:                PermissionCollection pc;
0842:                if ((pc = (PermissionCollection) loaderPC.get(codeUrl)) == null) {
0843:                    pc = super .getPermissions(codeSource);
0844:                    if (pc != null) {
0845:                        Iterator perms = permissionList.iterator();
0846:                        while (perms.hasNext()) {
0847:                            Permission p = (Permission) perms.next();
0848:                            pc.add(p);
0849:                        }
0850:                        loaderPC.put(codeUrl, pc);
0851:                    }
0852:                }
0853:                return (pc);
0854:
0855:            }
0856:
0857:            // ------------------------------------------------------ Protected Methods
0858:
0859:            /**
0860:             * Parse URL protocol.
0861:             *
0862:             * @return String protocol
0863:             */
0864:            protected static String parseProtocol(String spec) {
0865:                if (spec == null)
0866:                    return "";
0867:                int pos = spec.indexOf(':');
0868:                if (pos <= 0)
0869:                    return "";
0870:                return spec.substring(0, pos).trim();
0871:            }
0872:
0873:            /**
0874:             * Add a repository to our internal array only.
0875:             *
0876:             * @param repository The new repository
0877:             *
0878:             * @exception IllegalArgumentException if the manifest of a JAR file
0879:             *  cannot be processed correctly
0880:             */
0881:            protected void addRepositoryInternal(String repository) {
0882:
0883:                URLStreamHandler streamHandler = null;
0884:                String protocol = parseProtocol(repository);
0885:                if (factory != null)
0886:                    streamHandler = factory.createURLStreamHandler(protocol);
0887:
0888:                // Validate the manifest of a JAR file repository
0889:                if (!repository.endsWith(File.separator)
0890:                        && !repository.endsWith("/")) {
0891:                    JarFile jarFile = null;
0892:                    try {
0893:                        Manifest manifest = null;
0894:                        if (repository.startsWith("jar:")) {
0895:                            URL url = new URL(null, repository, streamHandler);
0896:                            JarURLConnection conn = (JarURLConnection) url
0897:                                    .openConnection();
0898:                            conn.setAllowUserInteraction(false);
0899:                            conn.setDoInput(true);
0900:                            conn.setDoOutput(false);
0901:                            conn.connect();
0902:                            jarFile = conn.getJarFile();
0903:                        } else if (repository.startsWith("file://")) {
0904:                            jarFile = new JarFile(repository.substring(7));
0905:                        } else if (repository.startsWith("file:")) {
0906:                            jarFile = new JarFile(repository.substring(5));
0907:                        } else if (repository.endsWith(".jar")) {
0908:                            URL url = new URL(null, repository, streamHandler);
0909:                            URLConnection conn = url.openConnection();
0910:                            JarInputStream jis = new JarInputStream(conn
0911:                                    .getInputStream());
0912:                            manifest = jis.getManifest();
0913:                        } else {
0914:                            throw new IllegalArgumentException(
0915:                                    "addRepositoryInternal:  Invalid URL '"
0916:                                            + repository + "'");
0917:                        }
0918:                    } catch (Throwable t) {
0919:                        IllegalArgumentException iae = new IllegalArgumentException(
0920:                                "addRepositoryInternal");
0921:                        jdkCompat.chainException(iae, t);
0922:                        throw iae;
0923:                    } finally {
0924:                        if (jarFile != null) {
0925:                            try {
0926:                                jarFile.close();
0927:                            } catch (Throwable t) {
0928:                            }
0929:                        }
0930:                    }
0931:                }
0932:
0933:                // Add this repository to our internal list
0934:                synchronized (repositories) {
0935:                    String results[] = new String[repositories.length + 1];
0936:                    System.arraycopy(repositories, 0, results, 0,
0937:                            repositories.length);
0938:                    results[repositories.length] = repository;
0939:                    repositories = results;
0940:                }
0941:
0942:            }
0943:
0944:            /**
0945:             * Convert an array of String to an array of URL and return it.
0946:             *
0947:             * @param input The array of String to be converted
0948:             */
0949:            protected static URL[] convert(String input[]) {
0950:                return convert(input, null);
0951:            }
0952:
0953:            /**
0954:             * Convert an array of String to an array of URL and return it.
0955:             *
0956:             * @param input The array of String to be converted
0957:             * @param factory Handler factory to use to generate the URLs
0958:             */
0959:            protected static URL[] convert(String input[],
0960:                    URLStreamHandlerFactory factory) {
0961:
0962:                URLStreamHandler streamHandler = null;
0963:
0964:                URL url[] = new URL[input.length];
0965:                for (int i = 0; i < url.length; i++) {
0966:                    try {
0967:                        String protocol = parseProtocol(input[i]);
0968:                        if (factory != null)
0969:                            streamHandler = factory
0970:                                    .createURLStreamHandler(protocol);
0971:                        else
0972:                            streamHandler = null;
0973:                        url[i] = new URL(null, input[i], streamHandler);
0974:                    } catch (MalformedURLException e) {
0975:                        url[i] = null;
0976:                    }
0977:                }
0978:                return (url);
0979:
0980:            }
0981:
0982:            /**
0983:             * Finds the resource with the given name if it has previously been
0984:             * loaded and cached by this class loader, and return an input stream
0985:             * to the resource data.  If this resource has not been cached, return
0986:             * <code>null</code>.
0987:             *
0988:             * @param name Name of the resource to return
0989:             */
0990:            protected InputStream findLoadedResource(String name) {
0991:
0992:                return (null); // FIXME - findLoadedResource()
0993:
0994:            }
0995:
0996:            /**
0997:             * Log a debugging output message.
0998:             *
0999:             * @param message Message to be logged
1000:             */
1001:            private void log(String message) {
1002:
1003:                System.out.println("StandardClassLoader: " + message);
1004:
1005:            }
1006:
1007:            /**
1008:             * Log a debugging output message with an exception.
1009:             *
1010:             * @param message Message to be logged
1011:             * @param throwable Exception to be logged
1012:             */
1013:            private void log(String message, Throwable throwable) {
1014:
1015:                System.out.println("StandardClassLoader: " + message);
1016:                throwable.printStackTrace(System.out);
1017:
1018:            }
1019:
1020:        }
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