java_lang_VMClassLoader.cc revision cb8f9e8a2941971c049b26745ea713c859342d9b 
1/*
2 * Copyright (C) 2008 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#include "class_linker.h"
18#include "jni_internal.h"
19#include "mirror/class_loader.h"
20#include "mirror/object-inl.h"
21#include "scoped_fast_native_object_access.h"
22#include "ScopedUtfChars.h"
23#include "zip_archive.h"
24
25namespace art {
26
27static jclass VMClassLoader_findLoadedClass(JNIEnv* env, jclass, jobject javaLoader, jstring javaName) {
28  ScopedFastNativeObjectAccess soa(env);
29  mirror::ClassLoader* loader = soa.Decode<mirror::ClassLoader*>(javaLoader);
30  ScopedUtfChars name(env, javaName);
31  if (name.c_str() == NULL) {
32    return NULL;
33  }
34
35  std::string descriptor(DotToDescriptor(name.c_str()));
36  mirror::Class* c = Runtime::Current()->GetClassLinker()->LookupClass(descriptor.c_str(), loader);
37  if (c != NULL && c->IsResolved()) {
38    return soa.AddLocalReference<jclass>(c);
39  } else {
40    // Class wasn't resolved so it may be erroneous or not yet ready, force the caller to go into
41    // the regular loadClass code.
42    return NULL;
43  }
44}
45
46static jint VMClassLoader_getBootClassPathSize(JNIEnv*, jclass) {
47  return Runtime::Current()->GetClassLinker()->GetBootClassPath().size();
48}
49
50/*
51 * Returns a string URL for a resource with the specified 'javaName' in
52 * entry 'index' of the boot class path.
53 *
54 * We return a newly-allocated String in the following form:
55 *
56 *   jar:file://path!/name
57 *
58 * Where "path" is the bootstrap class path entry and "name" is the string
59 * passed into this method.  "path" needs to be an absolute path (starting
60 * with '/'); if it's not we'd need to make it absolute as part of forming
61 * the URL string.
62 */
63static jstring VMClassLoader_getBootClassPathResource(JNIEnv* env, jclass, jstring javaName, jint index) {
64  ScopedUtfChars name(env, javaName);
65  if (name.c_str() == nullptr) {
66    return nullptr;
67  }
68
69  const std::vector<const DexFile*>& path = Runtime::Current()->GetClassLinker()->GetBootClassPath();
70  if (index < 0 || size_t(index) >= path.size()) {
71    return nullptr;
72  }
73  const DexFile* dex_file = path[index];
74
75  // For multidex locations, e.g., x.jar:classes2.dex, we want to look into x.jar.
76  const std::string& location(dex_file->GetBaseLocation());
77
78  std::string error_msg;
79  std::unique_ptr<ZipArchive> zip_archive(ZipArchive::Open(location.c_str(), &error_msg));
80  if (zip_archive.get() == nullptr) {
81    LOG(WARNING) << "Failed to open zip archive '" << location << "': " << error_msg;
82    return nullptr;
83  }
84  std::unique_ptr<ZipEntry> zip_entry(zip_archive->Find(name.c_str(), &error_msg));
85  if (zip_entry.get() == nullptr) {
86    return nullptr;
87  }
88
89  std::string url;
90  StringAppendF(&url, "jar:file://%s!/%s", location.c_str(), name.c_str());
91  return env->NewStringUTF(url.c_str());
92}
93
94static JNINativeMethod gMethods[] = {
95  NATIVE_METHOD(VMClassLoader, findLoadedClass, "!(Ljava/lang/ClassLoader;Ljava/lang/String;)Ljava/lang/Class;"),
96  NATIVE_METHOD(VMClassLoader, getBootClassPathResource, "(Ljava/lang/String;I)Ljava/lang/String;"),
97  NATIVE_METHOD(VMClassLoader, getBootClassPathSize, "!()I"),
98};
99
100void register_java_lang_VMClassLoader(JNIEnv* env) {
101  REGISTER_NATIVE_METHODS("java/lang/VMClassLoader");
102}
103
104}  // namespace art
105