/* * Copyright (c) 1999, 2001, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.sun.naming.internal; import java.io.InputStream;import java.io.IOException;import java.net.URL;import java.lang.ref.WeakReference;import java.lang.reflect.Method;import java.lang.reflect.InvocationTargetException;import java.util.Enumeration;import java.util.HashMap;import java.util.Hashtable;import java.util.Map;import java.util.Properties;import java.util.StringTokenizer;import java.util.List;import java.util.ArrayList;import java.util.WeakHashMap; import javax.naming.*; /** * The ResourceManager class facilitates the reading of JNDI resource files. * * @author Rosanna Lee * @author Scott Seligman */ public final class ResourceManager { /* * Name of provider resource files (without the package-name prefix.) */ private static final String PROVIDER_RESOURCE_FILE_NAME = "jndiprovider.properties"; /* * Name of application resource files. */ private static final String APP_RESOURCE_FILE_NAME = "jndi.properties"; /* * Name of properties file in <java.home>/lib. */ private static final String JRELIB_PROPERTY_FILE_NAME = "jndi.properties"; /* * The standard JNDI properties that specify colon-separated lists. */ private static final String[] listProperties = { Context.OBJECT_FACTORIES, Context.URL_PKG_PREFIXES, Context.STATE_FACTORIES, // The following shouldn't create a runtime dependence on ldap package. javax.naming.ldap.LdapContext.CONTROL_FACTORIES }; private static final VersionHelper helper = VersionHelper.getVersionHelper(); /* * A cache of the properties that have been constructed by * the ResourceManager. A Hashtable from a provider resource * file is keyed on a class in the resource file's package. * One from application resource files is keyed on the thread's * context class loader. */ private static final WeakHashMap propertiesCache = new WeakHashMap(11); /* * A cache of factory objects (ObjectFactory, StateFactory, ControlFactory). * * A two-level cache keyed first on context class loader and then * on propValue. Value is a list of class or factory objects, * weakly referenced so as not to prevent GC of the class loader. * Used in getFactories(). */ private static final WeakHashMap factoryCache = new WeakHashMap(11); /* * A cache of URL factory objects (ObjectFactory). * * A two-level cache keyed first on context class loader and then * on classSuffix+propValue. Value is the factory itself (weakly * referenced so as not to prevent GC of the class loader) or * NO_FACTORY if a previous search revealed no factory. Used in * getFactory(). */ private static final WeakHashMap urlFactoryCache = new WeakHashMap(11); private static final WeakReference NO_FACTORY = new WeakReference(null); /** * A class to allow JNDI properties be specified as applet parameters * without creating a static dependency on java.applet. */ private static class AppletParameter { private static final Class<?> clazz = getClass("java.applet.Applet"); private static final Method getMethod = getMethod(clazz, "getParameter", String.class); private static Class<?> getClass(String name) { try { return Class.forName(name, true, null); } catch (ClassNotFoundException e) { return null; } } private static Method getMethod(Class<?> clazz, String name, Class<?>... paramTypes) { if (clazz != null) { try { return clazz.getMethod(name, paramTypes); } catch (NoSuchMethodException e) { throw new AssertionError(e); } } else { return null; } } /** * Returns the value of the applet's named parameter. */ static Object get(Object applet, String name) { // if clazz is null then applet cannot be an Applet. if (clazz == null || !clazz.isInstance(applet)) throw new ClassCastException(applet.getClass().getName()); try { return getMethod.invoke(applet, name); } catch (InvocationTargetException e) { throw new AssertionError(e); } catch (IllegalAccessException iae) { throw new AssertionError(iae); } } } // There should be no instances of this class. private ResourceManager() { } // ---------- Public methods ---------- /* * Given the environment parameter passed to the initial context * constructor, returns the full environment for that initial * context (never null). This is based on the environment * parameter, the applet parameters (where appropriate), the * system properties, and all application resource files. * * <p> This method will modify <tt>env</tt> and save * a reference to it. The caller may no longer modify it. * * @param env environment passed to initial context constructor. * Null indicates an empty environment. * * @throws NamingException if an error occurs while reading a * resource file */ public static Hashtable getInitialEnvironment(Hashtable env) throws NamingException { String[] props = VersionHelper.PROPS; // system/applet properties if (env == null) { env = new Hashtable(11); } Object applet = env.get(Context.APPLET); // Merge property values from env param, applet params, and system // properties. The first value wins: there's no concatenation of // colon-separated lists. // Read system properties by first trying System.getProperties(), // and then trying System.getProperty() if that fails. The former // is more efficient due to fewer permission checks. // String[] jndiSysProps = helper.getJndiProperties(); for (int i = 0; i < props.length; i++) { Object val = env.get(props[i]); if (val == null) { if (applet != null) { val = AppletParameter.get(applet, props[i]); } if (val == null) { // Read system property. val = (jndiSysProps != null) ? jndiSysProps[i] : helper.getJndiProperty(i); } if (val != null) { env.put(props[i], val); } } } // Merge the above with the values read from all application // resource files. Colon-separated lists are concatenated. mergeTables(env, getApplicationResources()); return env; } /** * Retrieves the property from the environment, or from the provider * resource file associated with the given context. The environment * may in turn contain values that come from applet parameters, * system properties, or application resource files. * * If <tt>concat</tt> is true and both the environment and the provider * resource file contain the property, the two values are concatenated * (with a ':' separator). * * Returns null if no value is found. * * @param propName The non-null property name * @param env The possibly null environment properties * @param ctx The possibly null context * @param concat True if multiple values should be concatenated * @return the property value, or null is there is none. * @throws NamingException if an error occurs while reading the provider * resource file. */ public static String getProperty(String propName, Hashtable env, Context ctx, boolean concat) throws NamingException { String val1 = (env != null) ? (String)env.get(propName) : null; if ((ctx == null) || ((val1 != null) && !concat)) { return val1; } String val2 = (String)getProviderResource(ctx).get(propName); if (val1 == null) { return val2; } else if ((val2 == null) || !concat) { return val1; } else { return (val1 + ":" + val2); } } /** * Retrieves an enumeration of factory classes/object specified by a * property. * * The property is gotten from the environment and the provider * resource file associated with the given context and concantenated. * See getProperty(). The resulting property value is a list of class names. *<p> * This method then loads each class using the current thread's context * class loader and keeps them in a list. Any class that cannot be loaded * is ignored. The resulting list is then cached in a two-level * hash table, keyed first by the context class loader and then by * the property's value. * The next time threads of the same context class loader call this * method, they can use the cached list. *<p> * After obtaining the list either from the cache or by creating one from * the property value, this method then creates and returns a * FactoryEnumeration using the list. As the FactoryEnumeration is * traversed, the cached Class object in the list is instantiated and * replaced by an instance of the factory object itself. Both class * objects and factories are wrapped in weak references so as not to * prevent GC of the class loader. *<p> * Note that multiple threads can be accessing the same cached list * via FactoryEnumeration, which locks the list during each next(). * The size of the list will not change, * but a cached Class object might be replaced by an instantiated factory * object. * * @param propName The non-null property name * @param env The possibly null environment properties * @param ctx The possibly null context * @return An enumeration of factory classes/objects; null if none. * @exception NamingException If encounter problem while reading the provider * property file. * @see javax.naming.spi.NamingManager#getObjectInstance * @see javax.naming.spi.NamingManager#getStateToBind * @see javax.naming.spi.DirectoryManager#getObjectInstance * @see javax.naming.spi.DirectoryManager#getStateToBind * @see javax.naming.ldap.ControlFactory#getControlInstance */ public static FactoryEnumeration getFactories(String propName, Hashtable env, Context ctx) throws NamingException { String facProp = getProperty(propName, env, ctx, true); if (facProp == null) return null; // no classes specified; return null // Cache is based on context class loader and property val ClassLoader loader = helper.getContextClassLoader(); Map perLoaderCache = null; synchronized (factoryCache) { perLoaderCache = (Map) factoryCache.get(loader); if (perLoaderCache == null) { perLoaderCache = new HashMap(11); factoryCache.put(loader, perLoaderCache); } } synchronized (perLoaderCache) { List factories = (List) perLoaderCache.get(facProp); if (factories != null) { // Cached list return factories.size() == 0 ? null : new FactoryEnumeration(factories, loader); } else { // Populate list with classes named in facProp; skipping // those that we cannot load StringTokenizer parser = new StringTokenizer(facProp, ":"); factories = new ArrayList(5); while (parser.hasMoreTokens()) { try { // System.out.println("loading"); String className = parser.nextToken(); Class c = helper.loadClass(className, loader); factories.add(new NamedWeakReference(c, className)); } catch (Exception e) { // ignore ClassNotFoundException, IllegalArgumentException } } // System.out.println("adding to cache: " + factories); perLoaderCache.put(facProp, factories); return new FactoryEnumeration(factories, loader); } } } /** * Retrieves a factory from a list of packages specified in a * property. * * The property is gotten from the environment and the provider * resource file associated with the given context and concatenated. * classSuffix is added to the end of this list. * See getProperty(). The resulting property value is a list of package * prefixes. *<p> * This method then constructs a list of class names by concatenating * each package prefix with classSuffix and attempts to load and * instantiate the class until one succeeds. * Any class that cannot be loaded is ignored. * The resulting object is then cached in a two-level hash table, * keyed first by the context class loader and then by the property's * value and classSuffix. * The next time threads of the same context class loader call this * method, they use the cached factory. * If no factory can be loaded, NO_FACTORY is recorded in the table * so that next time it'll return quickly. * * @param propName The non-null property name * @param env The possibly null environment properties * @param ctx The possibly null context * @param classSuffix The non-null class name * (e.g. ".ldap.ldapURLContextFactory). * @param defaultPkgPrefix The non-null default package prefix. * (e.g., "com.sun.jndi.url"). * @return An factory object; null if none. * @exception NamingException If encounter problem while reading the provider * property file, or problem instantiating the factory. * * @see javax.naming.spi.NamingManager#getURLContext * @see javax.naming.spi.NamingManager#getURLObject */ public static Object getFactory(String propName, Hashtable env, Context ctx, String classSuffix, String defaultPkgPrefix) throws NamingException { // Merge property with provider property and supplied default String facProp = getProperty(propName, env, ctx, true); if (facProp != null) facProp += (":" + defaultPkgPrefix); else facProp = defaultPkgPrefix; // Cache factory based on context class loader, class name, and // property val ClassLoader loader = helper.getContextClassLoader(); String key = classSuffix + " " + facProp; Map perLoaderCache = null; synchronized (urlFactoryCache) { perLoaderCache = (Map) urlFactoryCache.get(loader); if (perLoaderCache == null) { perLoaderCache = new HashMap(11); urlFactoryCache.put(loader, perLoaderCache); } } synchronized (perLoaderCache) { Object factory = null; WeakReference factoryRef = (WeakReference) perLoaderCache.get(key); if (factoryRef == NO_FACTORY) { return null; } else if (factoryRef != null) { factory = factoryRef.get(); if (factory != null) { // check if weak ref has been cleared return factory; } } // Not cached; find first factory and cache StringTokenizer parser = new StringTokenizer(facProp, ":"); String className; while (factory == null && parser.hasMoreTokens()) { className = parser.nextToken() + classSuffix; try { // System.out.println("loading " + className); factory = helper.loadClass(className, loader).newInstance(); } catch (InstantiationException e) { NamingException ne = new NamingException("Cannot instantiate " + className); ne.setRootCause(e); throw ne; } catch (IllegalAccessException e) { NamingException ne = new NamingException("Cannot access " + className); ne.setRootCause(e); throw ne; } catch (Exception e) { // ignore ClassNotFoundException, IllegalArgumentException, // etc. } } // Cache it. perLoaderCache.put(key, (factory != null) ? new WeakReference(factory) : NO_FACTORY); return factory; } } // ---------- Private methods ---------- /* * Returns the properties contained in the provider resource file * of an object's package. Returns an empty hash table if the * object is null or the resource file cannot be found. The * results are cached. * * @throws NamingException if an error occurs while reading the file. */ private static Hashtable getProviderResource(Object obj) throws NamingException { if (obj == null) { return (new Hashtable(1)); } synchronized (propertiesCache) { Class c = obj.getClass(); Hashtable props = (Hashtable)propertiesCache.get(c); if (props != null) { return props; } props = new Properties(); InputStream istream = helper.getResourceAsStream(c, PROVIDER_RESOURCE_FILE_NAME); if (istream != null) { try { ((Properties)props).load(istream); } catch (IOException e) { NamingException ne = new ConfigurationException( "Error reading provider resource file for " + c); ne.setRootCause(e); throw ne; } } propertiesCache.put(c, props); return props;Lines 1–500 of 608. Load more
/* * Copyright (c) 1999, 2001, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package com.sun.naming.internal; import java.io.InputStream; import java.io.IOException; import java.net.URL; import java.lang.ref.WeakReference; import java.lang.reflect.Method; import java.lang.reflect.InvocationTargetException; import java.util.Enumeration; import java.util.HashMap; import java.util.Hashtable; import java.util.Map; import java.util.Properties; import java.util.StringTokenizer; import java.util.List; import java.util.ArrayList; import java.util.WeakHashMap; import javax.naming.*; /** * The ResourceManager class facilitates the reading of JNDI resource files. * * @author Rosanna Lee * @author Scott Seligman */ public final class ResourceManager { /* * Name of provider resource files (without the package-name prefix.) */ private static final String PROVIDER_RESOURCE_FILE_NAME = "jndiprovider.properties"; /* * Name of application resource files. */ private static final String APP_RESOURCE_FILE_NAME = "jndi.properties"; /* * Name of properties file in <java.home>/lib. */ private static final String JRELIB_PROPERTY_FILE_NAME = "jndi.properties"; /* * The standard JNDI properties that specify colon-separated lists. */ private static final String[] listProperties = { Context.OBJECT_FACTORIES, Context.URL_PKG_PREFIXES, Context.STATE_FACTORIES, // The following shouldn't create a runtime dependence on ldap package. javax.naming.ldap.LdapContext.CONTROL_FACTORIES }; private static final VersionHelper helper = VersionHelper.getVersionHelper(); /* * A cache of the properties that have been constructed by * the ResourceManager. A Hashtable from a provider resource * file is keyed on a class in the resource file's package. * One from application resource files is keyed on the thread's * context class loader. */ private static final WeakHashMap propertiesCache = new WeakHashMap(11); /* * A cache of factory objects (ObjectFactory, StateFactory, ControlFactory). * * A two-level cache keyed first on context class loader and then * on propValue. Value is a list of class or factory objects, * weakly referenced so as not to prevent GC of the class loader. * Used in getFactories(). */ private static final WeakHashMap factoryCache = new WeakHashMap(11); /* * A cache of URL factory objects (ObjectFactory). * * A two-level cache keyed first on context class loader and then * on classSuffix+propValue. Value is the factory itself (weakly * referenced so as not to prevent GC of the class loader) or * NO_FACTORY if a previous search revealed no factory. Used in * getFactory(). */ private static final WeakHashMap urlFactoryCache = new WeakHashMap(11); private static final WeakReference NO_FACTORY = new WeakReference(null); /** * A class to allow JNDI properties be specified as applet parameters * without creating a static dependency on java.applet. */ private static class AppletParameter { private static final Class<?> clazz = getClass("java.applet.Applet"); private static final Method getMethod = getMethod(clazz, "getParameter", String.class); private static Class<?> getClass(String name) { try { return Class.forName(name, true, null); } catch (ClassNotFoundException e) { return null; } } private static Method getMethod(Class<?> clazz, String name, Class<?>... paramTypes) { if (clazz != null) { try { return clazz.getMethod(name, paramTypes); } catch (NoSuchMethodException e) { throw new AssertionError(e); } } else { return null; } } /** * Returns the value of the applet's named parameter. */ static Object get(Object applet, String name) { // if clazz is null then applet cannot be an Applet. if (clazz == null || !clazz.isInstance(applet)) throw new ClassCastException(applet.getClass().getName()); try { return getMethod.invoke(applet, name); } catch (InvocationTargetException e) { throw new AssertionError(e); } catch (IllegalAccessException iae) { throw new AssertionError(iae); } } } // There should be no instances of this class. private ResourceManager() { } // ---------- Public methods ---------- /* * Given the environment parameter passed to the initial context * constructor, returns the full environment for that initial * context (never null). This is based on the environment * parameter, the applet parameters (where appropriate), the * system properties, and all application resource files. * * <p> This method will modify <tt>env</tt> and save * a reference to it. The caller may no longer modify it. * * @param env environment passed to initial context constructor. * Null indicates an empty environment. * * @throws NamingException if an error occurs while reading a * resource file */ public static Hashtable getInitialEnvironment(Hashtable env) throws NamingException { String[] props = VersionHelper.PROPS; // system/applet properties if (env == null) { env = new Hashtable(11); } Object applet = env.get(Context.APPLET); // Merge property values from env param, applet params, and system // properties. The first value wins: there's no concatenation of // colon-separated lists. // Read system properties by first trying System.getProperties(), // and then trying System.getProperty() if that fails. The former // is more efficient due to fewer permission checks. // String[] jndiSysProps = helper.getJndiProperties(); for (int i = 0; i < props.length; i++) { Object val = env.get(props[i]); if (val == null) { if (applet != null) { val = AppletParameter.get(applet, props[i]); } if (val == null) { // Read system property. val = (jndiSysProps != null) ? jndiSysProps[i] : helper.getJndiProperty(i); } if (val != null) { env.put(props[i], val); } } } // Merge the above with the values read from all application // resource files. Colon-separated lists are concatenated. mergeTables(env, getApplicationResources()); return env; } /** * Retrieves the property from the environment, or from the provider * resource file associated with the given context. The environment * may in turn contain values that come from applet parameters, * system properties, or application resource files. * * If <tt>concat</tt> is true and both the environment and the provider * resource file contain the property, the two values are concatenated * (with a ':' separator). * * Returns null if no value is found. * * @param propName The non-null property name * @param env The possibly null environment properties * @param ctx The possibly null context * @param concat True if multiple values should be concatenated * @return the property value, or null is there is none. * @throws NamingException if an error occurs while reading the provider * resource file. */ public static String getProperty(String propName, Hashtable env, Context ctx, boolean concat) throws NamingException { String val1 = (env != null) ? (String)env.get(propName) : null; if ((ctx == null) || ((val1 != null) && !concat)) { return val1; } String val2 = (String)getProviderResource(ctx).get(propName); if (val1 == null) { return val2; } else if ((val2 == null) || !concat) { return val1; } else { return (val1 + ":" + val2); } } /** * Retrieves an enumeration of factory classes/object specified by a * property. * * The property is gotten from the environment and the provider * resource file associated with the given context and concantenated. * See getProperty(). The resulting property value is a list of class names. *<p> * This method then loads each class using the current thread's context * class loader and keeps them in a list. Any class that cannot be loaded * is ignored. The resulting list is then cached in a two-level * hash table, keyed first by the context class loader and then by * the property's value. * The next time threads of the same context class loader call this * method, they can use the cached list. *<p> * After obtaining the list either from the cache or by creating one from * the property value, this method then creates and returns a * FactoryEnumeration using the list. As the FactoryEnumeration is * traversed, the cached Class object in the list is instantiated and * replaced by an instance of the factory object itself. Both class * objects and factories are wrapped in weak references so as not to * prevent GC of the class loader. *<p> * Note that multiple threads can be accessing the same cached list * via FactoryEnumeration, which locks the list during each next(). * The size of the list will not change, * but a cached Class object might be replaced by an instantiated factory * object. * * @param propName The non-null property name * @param env The possibly null environment properties * @param ctx The possibly null context * @return An enumeration of factory classes/objects; null if none. * @exception NamingException If encounter problem while reading the provider * property file. * @see javax.naming.spi.NamingManager#getObjectInstance * @see javax.naming.spi.NamingManager#getStateToBind * @see javax.naming.spi.DirectoryManager#getObjectInstance * @see javax.naming.spi.DirectoryManager#getStateToBind * @see javax.naming.ldap.ControlFactory#getControlInstance */ public static FactoryEnumeration getFactories(String propName, Hashtable env, Context ctx) throws NamingException { String facProp = getProperty(propName, env, ctx, true); if (facProp == null) return null; // no classes specified; return null // Cache is based on context class loader and property val ClassLoader loader = helper.getContextClassLoader(); Map perLoaderCache = null; synchronized (factoryCache) { perLoaderCache = (Map) factoryCache.get(loader); if (perLoaderCache == null) { perLoaderCache = new HashMap(11); factoryCache.put(loader, perLoaderCache); } } synchronized (perLoaderCache) { List factories = (List) perLoaderCache.get(facProp); if (factories != null) { // Cached list return factories.size() == 0 ? null : new FactoryEnumeration(factories, loader); } else { // Populate list with classes named in facProp; skipping // those that we cannot load StringTokenizer parser = new StringTokenizer(facProp, ":"); factories = new ArrayList(5); while (parser.hasMoreTokens()) { try { // System.out.println("loading"); String className = parser.nextToken(); Class c = helper.loadClass(className, loader); factories.add(new NamedWeakReference(c, className)); } catch (Exception e) { // ignore ClassNotFoundException, IllegalArgumentException } } // System.out.println("adding to cache: " + factories); perLoaderCache.put(facProp, factories); return new FactoryEnumeration(factories, loader); } } } /** * Retrieves a factory from a list of packages specified in a * property. * * The property is gotten from the environment and the provider * resource file associated with the given context and concatenated. * classSuffix is added to the end of this list. * See getProperty(). The resulting property value is a list of package * prefixes. *<p> * This method then constructs a list of class names by concatenating * each package prefix with classSuffix and attempts to load and * instantiate the class until one succeeds. * Any class that cannot be loaded is ignored. * The resulting object is then cached in a two-level hash table, * keyed first by the context class loader and then by the property's * value and classSuffix. * The next time threads of the same context class loader call this * method, they use the cached factory. * If no factory can be loaded, NO_FACTORY is recorded in the table * so that next time it'll return quickly. * * @param propName The non-null property name * @param env The possibly null environment properties * @param ctx The possibly null context * @param classSuffix The non-null class name * (e.g. ".ldap.ldapURLContextFactory). * @param defaultPkgPrefix The non-null default package prefix. * (e.g., "com.sun.jndi.url"). * @return An factory object; null if none. * @exception NamingException If encounter problem while reading the provider * property file, or problem instantiating the factory. * * @see javax.naming.spi.NamingManager#getURLContext * @see javax.naming.spi.NamingManager#getURLObject */ public static Object getFactory(String propName, Hashtable env, Context ctx, String classSuffix, String defaultPkgPrefix) throws NamingException { // Merge property with provider property and supplied default String facProp = getProperty(propName, env, ctx, true); if (facProp != null) facProp += (":" + defaultPkgPrefix); else facProp = defaultPkgPrefix; // Cache factory based on context class loader, class name, and // property val ClassLoader loader = helper.getContextClassLoader(); String key = classSuffix + " " + facProp; Map perLoaderCache = null; synchronized (urlFactoryCache) { perLoaderCache = (Map) urlFactoryCache.get(loader); if (perLoaderCache == null) { perLoaderCache = new HashMap(11); urlFactoryCache.put(loader, perLoaderCache); } } synchronized (perLoaderCache) { Object factory = null; WeakReference factoryRef = (WeakReference) perLoaderCache.get(key); if (factoryRef == NO_FACTORY) { return null; } else if (factoryRef != null) { factory = factoryRef.get(); if (factory != null) { // check if weak ref has been cleared return factory; } } // Not cached; find first factory and cache StringTokenizer parser = new StringTokenizer(facProp, ":"); String className; while (factory == null && parser.hasMoreTokens()) { className = parser.nextToken() + classSuffix; try { // System.out.println("loading " + className); factory = helper.loadClass(className, loader).newInstance(); } catch (InstantiationException e) { NamingException ne = new NamingException("Cannot instantiate " + className); ne.setRootCause(e); throw ne; } catch (IllegalAccessException e) { NamingException ne = new NamingException("Cannot access " + className); ne.setRootCause(e); throw ne; } catch (Exception e) { // ignore ClassNotFoundException, IllegalArgumentException, // etc. } } // Cache it. perLoaderCache.put(key, (factory != null) ? new WeakReference(factory) : NO_FACTORY); return factory; } } // ---------- Private methods ---------- /* * Returns the properties contained in the provider resource file * of an object's package. Returns an empty hash table if the * object is null or the resource file cannot be found. The * results are cached. * * @throws NamingException if an error occurs while reading the file. */ private static Hashtable getProviderResource(Object obj) throws NamingException { if (obj == null) { return (new Hashtable(1)); } synchronized (propertiesCache) { Class c = obj.getClass(); Hashtable props = (Hashtable)propertiesCache.get(c); if (props != null) { return props; } props = new Properties(); InputStream istream = helper.getResourceAsStream(c, PROVIDER_RESOURCE_FILE_NAME); if (istream != null) { try { ((Properties)props).load(istream); } catch (IOException e) { NamingException ne = new ConfigurationException( "Error reading provider resource file for " + c); ne.setRootCause(e); throw ne; } } propertiesCache.put(c, props); return props;