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Diffstat (limited to 'infrastructure/rhino1_7R1/src/org/mozilla/javascript/ClassCache.java')
-rw-r--r-- | infrastructure/rhino1_7R1/src/org/mozilla/javascript/ClassCache.java | 220 |
1 files changed, 220 insertions, 0 deletions
diff --git a/infrastructure/rhino1_7R1/src/org/mozilla/javascript/ClassCache.java b/infrastructure/rhino1_7R1/src/org/mozilla/javascript/ClassCache.java new file mode 100644 index 0000000..9047278 --- /dev/null +++ b/infrastructure/rhino1_7R1/src/org/mozilla/javascript/ClassCache.java @@ -0,0 +1,220 @@ +/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- + * + * ***** BEGIN LICENSE BLOCK ***** + * Version: MPL 1.1/GPL 2.0 + * + * The contents of this file are subject to the Mozilla Public License Version + * 1.1 (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.mozilla.org/MPL/ + * + * Software distributed under the License is distributed on an "AS IS" basis, + * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License + * for the specific language governing rights and limitations under the + * License. + * + * The Original Code is Rhino code, released + * May 6, 1999. + * + * The Initial Developer of the Original Code is + * Netscape Communications Corporation. + * Portions created by the Initial Developer are Copyright (C) 1997-1999 + * the Initial Developer. All Rights Reserved. + * + * Contributor(s): + * Igor Bukanov, igor@fastmail.fm + * Norris Boyd + * + * Alternatively, the contents of this file may be used under the terms of + * the GNU General Public License Version 2 or later (the "GPL"), in which + * case the provisions of the GPL are applicable instead of those above. If + * you wish to allow use of your version of this file only under the terms of + * the GPL and not to allow others to use your version of this file under the + * MPL, indicate your decision by deleting the provisions above and replacing + * them with the notice and other provisions required by the GPL. If you do + * not delete the provisions above, a recipient may use your version of this + * file under either the MPL or the GPL. + * + * ***** END LICENSE BLOCK ***** */ + +package org.mozilla.javascript; + +import java.util.Map; +import java.util.HashMap; + +/** + * Cache of generated classes and data structures to access Java runtime + * from JavaScript. + * + * @author Igor Bukanov + * + * @since Rhino 1.5 Release 5 + */ +public class ClassCache +{ + private static final Object AKEY = new Object(); + private volatile boolean cachingIsEnabled = true; + private HashMap<Class<?>,JavaMembers> classTable + = new HashMap<Class<?>,JavaMembers>(); + private HashMap<Class<?>,JavaMembers> javaAdapterGeneratedClasses + = new HashMap<Class<?>,JavaMembers>(); + private HashMap<JavaAdapter.JavaAdapterSignature,Class<?>> classAdapterCache + = new HashMap<JavaAdapter.JavaAdapterSignature,Class<?>>(); + private HashMap<Class<?>,Object> interfaceAdapterCache; + private int generatedClassSerial; + + /** + * Search for ClassCache object in the given scope. + * The method first calls + * {@link ScriptableObject#getTopLevelScope(Scriptable scope)} + * to get the top most scope and then tries to locate associated + * ClassCache object in the prototype chain of the top scope. + * + * @param scope scope to search for ClassCache object. + * @return previously associated ClassCache object or a new instance of + * ClassCache if no ClassCache object was found. + * + * @see #associate(ScriptableObject topScope) + */ + public static ClassCache get(Scriptable scope) + { + ClassCache cache = (ClassCache) + ScriptableObject.getTopScopeValue(scope, AKEY); + if (cache == null) { + throw new RuntimeException("Can't find top level scope for " + + "ClassCache.get"); + } + return cache; + } + + /** + * Associate ClassCache object with the given top-level scope. + * The ClassCache object can only be associated with the given scope once. + * + * @param topScope scope to associate this ClassCache object with. + * @return true if no previous ClassCache objects were embedded into + * the scope and this ClassCache were successfully associated + * or false otherwise. + * + * @see #get(Scriptable scope) + */ + public boolean associate(ScriptableObject topScope) + { + if (topScope.getParentScope() != null) { + // Can only associate cache with top level scope + throw new IllegalArgumentException(); + } + if (this == topScope.associateValue(AKEY, this)) { + return true; + } + return false; + } + + /** + * Empty caches of generated Java classes and Java reflection information. + */ + public synchronized void clearCaches() + { + classTable.clear(); + javaAdapterGeneratedClasses.clear(); + classAdapterCache.clear(); + interfaceAdapterCache = null; + } + + /** + * Check if generated Java classes and Java reflection information + * is cached. + */ + public final boolean isCachingEnabled() + { + return cachingIsEnabled; + } + + /** + * Set whether to cache some values. + * <p> + * By default, the engine will cache the results of + * <tt>Class.getMethods()</tt> and similar calls. + * This can speed execution dramatically, but increases the memory + * footprint. Also, with caching enabled, references may be held to + * objects past the lifetime of any real usage. + * <p> + * If caching is enabled and this method is called with a + * <code>false</code> argument, the caches will be emptied. + * <p> + * Caching is enabled by default. + * + * @param enabled if true, caching is enabled + * + * @see #clearCaches() + */ + public synchronized void setCachingEnabled(boolean enabled) + { + if (enabled == cachingIsEnabled) + return; + if (!enabled) + clearCaches(); + cachingIsEnabled = enabled; + } + + /** + * @return a map from classes to associated JavaMembers objects + */ + Map<Class<?>,JavaMembers> getClassCacheMap() { + return classTable; + } + + Map<JavaAdapter.JavaAdapterSignature,Class<?>> getInterfaceAdapterCacheMap() + { + return classAdapterCache; + } + + /** + * @deprecated + * The method always returns false. + * @see #setInvokerOptimizationEnabled(boolean enabled) + */ + public boolean isInvokerOptimizationEnabled() + { + return false; + } + + /** + * @deprecated + * The method does nothing. + * Invoker optimization is no longer used by Rhino. + * On modern JDK like 1.4 or 1.5 the disadvantages of the optimization + * like increased memory usage or longer initialization time overweight + * small speed increase that can be gained using generated proxy class + * to replace reflection. + */ + public synchronized void setInvokerOptimizationEnabled(boolean enabled) + { + } + + /** + * Internal engine method to return serial number for generated classes + * to ensure name uniqueness. + */ + public final synchronized int newClassSerialNumber() + { + return ++generatedClassSerial; + } + + Object getInterfaceAdapter(Class<?> cl) + { + return interfaceAdapterCache == null + ? null + : interfaceAdapterCache.get(cl); + } + + synchronized void cacheInterfaceAdapter(Class<?> cl, Object iadapter) + { + if (cachingIsEnabled) { + if (interfaceAdapterCache == null) { + interfaceAdapterCache = new HashMap<Class<?>,Object>(); + } + interfaceAdapterCache.put(cl, iadapter); + } + } +} |