1 /* 2 * Copyright (C) 2006 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.app; 18 19 import android.os.Trace; 20 import dalvik.system.PathClassLoader; 21 22 import java.util.HashMap; 23 import java.util.Map; 24 25 class ApplicationLoaders 26 { 27 public static ApplicationLoaders getDefault() 28 { 29 return gApplicationLoaders; 30 } 31 32 public ClassLoader getClassLoader(String zip, String libPath, ClassLoader parent) 33 { 34 /* 35 * This is the parent we use if they pass "null" in. In theory 36 * this should be the "system" class loader; in practice we 37 * don't use that and can happily (and more efficiently) use the 38 * bootstrap class loader. 39 */ 40 ClassLoader baseParent = ClassLoader.getSystemClassLoader().getParent(); 41 42 synchronized (mLoaders) { 43 if (parent == null) { 44 parent = baseParent; 45 } 46 47 /* 48 * If we're one step up from the base class loader, find 49 * something in our cache. Otherwise, we create a whole 50 * new ClassLoader for the zip archive. 51 */ 52 if (parent == baseParent) { 53 ClassLoader loader = mLoaders.get(zip); 54 if (loader != null) { 55 return loader; 56 } 57 58 Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, zip); 59 PathClassLoader pathClassloader = 60 new PathClassLoader(zip, libPath, parent); 61 Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER); 62 63 mLoaders.put(zip, pathClassloader); 64 return pathClassloader; 65 } 66 67 Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, zip); 68 PathClassLoader pathClassloader = new PathClassLoader(zip, parent); 69 Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER); 70 return pathClassloader; 71 } 72 } 73 74 private final Map<String, ClassLoader> mLoaders = new HashMap<String, ClassLoader>(); 75 76 private static final ApplicationLoaders gApplicationLoaders 77 = new ApplicationLoaders(); 78 } 79