1 /* 2 * Copyright (C) 2016 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 com.android.internal.os; 18 19 import android.os.Trace; 20 21 import dalvik.system.DelegateLastClassLoader; 22 import dalvik.system.DexClassLoader; 23 import dalvik.system.PathClassLoader; 24 25 /** 26 * Creates class loaders. 27 * 28 * @hide 29 */ 30 public class ClassLoaderFactory { 31 // Unconstructable 32 private ClassLoaderFactory() {} 33 34 private static final String PATH_CLASS_LOADER_NAME = PathClassLoader.class.getName(); 35 private static final String DEX_CLASS_LOADER_NAME = DexClassLoader.class.getName(); 36 private static final String DELEGATE_LAST_CLASS_LOADER_NAME = 37 DelegateLastClassLoader.class.getName(); 38 39 /** 40 * Returns true if {@code name} is a supported classloader. {@code name} must be a 41 * binary name of a class, as defined by {@code Class.getName}. 42 */ 43 public static boolean isValidClassLoaderName(String name) { 44 // This method is used to parse package data and does not accept null names. 45 return name != null && (isPathClassLoaderName(name) || isDelegateLastClassLoaderName(name)); 46 } 47 48 /** 49 * Returns true if {@code name} is the encoding for either PathClassLoader or DexClassLoader. 50 * The two class loaders are grouped together because they have the same behaviour. 51 */ 52 public static boolean isPathClassLoaderName(String name) { 53 // For null values we default to PathClassLoader. This cover the case when packages 54 // don't specify any value for their class loaders. 55 return name == null || PATH_CLASS_LOADER_NAME.equals(name) || 56 DEX_CLASS_LOADER_NAME.equals(name); 57 } 58 59 /** 60 * Returns true if {@code name} is the encoding for the DelegateLastClassLoader. 61 */ 62 public static boolean isDelegateLastClassLoaderName(String name) { 63 return DELEGATE_LAST_CLASS_LOADER_NAME.equals(name); 64 } 65 66 /** 67 * Same as {@code createClassLoader} below, except that no associated namespace 68 * is created. 69 */ 70 public static ClassLoader createClassLoader(String dexPath, 71 String librarySearchPath, ClassLoader parent, String classloaderName) { 72 if (isPathClassLoaderName(classloaderName)) { 73 return new PathClassLoader(dexPath, librarySearchPath, parent); 74 } else if (isDelegateLastClassLoaderName(classloaderName)) { 75 return new DelegateLastClassLoader(dexPath, librarySearchPath, parent); 76 } 77 78 throw new AssertionError("Invalid classLoaderName: " + classloaderName); 79 } 80 81 /** 82 * Create a ClassLoader and initialize a linker-namespace for it. 83 */ 84 public static ClassLoader createClassLoader(String dexPath, 85 String librarySearchPath, String libraryPermittedPath, ClassLoader parent, 86 int targetSdkVersion, boolean isNamespaceShared, String classloaderName) { 87 88 final ClassLoader classLoader = createClassLoader(dexPath, librarySearchPath, parent, 89 classloaderName); 90 91 boolean isForVendor = false; 92 for (String path : dexPath.split(":")) { 93 if (path.startsWith("/vendor/")) { 94 isForVendor = true; 95 break; 96 } 97 } 98 Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "createClassloaderNamespace"); 99 String errorMessage = createClassloaderNamespace(classLoader, 100 targetSdkVersion, 101 librarySearchPath, 102 libraryPermittedPath, 103 isNamespaceShared, 104 isForVendor); 105 Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER); 106 107 if (errorMessage != null) { 108 throw new UnsatisfiedLinkError("Unable to create namespace for the classloader " + 109 classLoader + ": " + errorMessage); 110 } 111 112 return classLoader; 113 } 114 115 private static native String createClassloaderNamespace(ClassLoader classLoader, 116 int targetSdkVersion, 117 String librarySearchPath, 118 String libraryPermittedPath, 119 boolean isNamespaceShared, 120 boolean isForVendor); 121 } 122