java_lang_Class.cc revision c114b5fbc91e6d19ef430d9bc3468386ca61b324 
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 "dex_file-inl.h"
19#include "jni_internal.h"
20#include "nth_caller_visitor.h"
21#include "mirror/class-inl.h"
22#include "mirror/class_loader.h"
23#include "mirror/object-inl.h"
24#include "scoped_thread_state_change.h"
25#include "scoped_fast_native_object_access.h"
26#include "ScopedLocalRef.h"
27#include "ScopedUtfChars.h"
28#include "well_known_classes.h"
29
30namespace art {
31
32static mirror::Class* DecodeClass(const ScopedFastNativeObjectAccess& soa, jobject java_class)
33    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
34  mirror::Class* c = soa.Decode<mirror::Class*>(java_class);
35  DCHECK(c != NULL);
36  DCHECK(c->IsClass());
37  // TODO: we could EnsureInitialized here, rather than on every reflective get/set or invoke .
38  // For now, we conservatively preserve the old dalvik behavior. A quick "IsInitialized" check
39  // every time probably doesn't make much difference to reflection performance anyway.
40  return c;
41}
42
43// "name" is in "binary name" format, e.g. "dalvik.system.Debug$1".
44static jclass Class_classForName(JNIEnv* env, jclass, jstring javaName, jboolean initialize,
45                                 jobject javaLoader) {
46  ScopedFastNativeObjectAccess soa(env);
47  ScopedUtfChars name(env, javaName);
48  if (name.c_str() == nullptr) {
49    return nullptr;
50  }
51
52  // We need to validate and convert the name (from x.y.z to x/y/z).  This
53  // is especially handy for array types, since we want to avoid
54  // auto-generating bogus array classes.
55  if (!IsValidBinaryClassName(name.c_str())) {
56    ThrowLocation throw_location = soa.Self()->GetCurrentLocationForThrow();
57    soa.Self()->ThrowNewExceptionF(throw_location, "Ljava/lang/ClassNotFoundException;",
58                                   "Invalid name: %s", name.c_str());
59    return nullptr;
60  }
61
62  std::string descriptor(DotToDescriptor(name.c_str()));
63  StackHandleScope<2> hs(soa.Self());
64  Handle<mirror::ClassLoader> class_loader(hs.NewHandle(soa.Decode<mirror::ClassLoader*>(javaLoader)));
65  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
66  Handle<mirror::Class> c(
67      hs.NewHandle(class_linker->FindClass(soa.Self(), descriptor.c_str(), class_loader)));
68  if (c.Get() == nullptr) {
69    ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred());
70    env->ExceptionClear();
71    jthrowable cnfe = reinterpret_cast<jthrowable>(env->NewObject(WellKnownClasses::java_lang_ClassNotFoundException,
72                                                                  WellKnownClasses::java_lang_ClassNotFoundException_init,
73                                                                  javaName, cause.get()));
74    if (cnfe != nullptr) {
75      // Make sure allocation didn't fail with an OOME.
76      env->Throw(cnfe);
77    }
78    return nullptr;
79  }
80  if (initialize) {
81    class_linker->EnsureInitialized(c, true, true);
82  }
83  return soa.AddLocalReference<jclass>(c.Get());
84}
85
86static jstring Class_getNameNative(JNIEnv* env, jobject javaThis) {
87  ScopedFastNativeObjectAccess soa(env);
88  StackHandleScope<1> hs(soa.Self());
89  mirror::Class* const c = DecodeClass(soa, javaThis);
90  return soa.AddLocalReference<jstring>(mirror::Class::ComputeName(hs.NewHandle(c)));
91}
92
93static jobjectArray Class_getProxyInterfaces(JNIEnv* env, jobject javaThis) {
94  ScopedFastNativeObjectAccess soa(env);
95  mirror::Class* c = DecodeClass(soa, javaThis);
96  return soa.AddLocalReference<jobjectArray>(c->GetInterfaces()->Clone(soa.Self()));
97}
98
99static JNINativeMethod gMethods[] = {
100  NATIVE_METHOD(Class, classForName, "!(Ljava/lang/String;ZLjava/lang/ClassLoader;)Ljava/lang/Class;"),
101  NATIVE_METHOD(Class, getNameNative, "!()Ljava/lang/String;"),
102  NATIVE_METHOD(Class, getProxyInterfaces, "!()[Ljava/lang/Class;"),
103};
104
105void register_java_lang_Class(JNIEnv* env) {
106  REGISTER_NATIVE_METHODS("java/lang/Class");
107}
108
109}  // namespace art
110