java_lang_Class.cc revision 0aa50ce2fb75bfc2e815a0c33adf9b049561923b 
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 "java_lang_Class.h"
18
19#include "class_linker.h"
20#include "dex_file-inl.h"
21#include "jni_internal.h"
22#include "nth_caller_visitor.h"
23#include "mirror/class-inl.h"
24#include "mirror/class_loader.h"
25#include "mirror/object-inl.h"
26#include "scoped_thread_state_change.h"
27#include "scoped_fast_native_object_access.h"
28#include "ScopedLocalRef.h"
29#include "ScopedUtfChars.h"
30#include "well_known_classes.h"
31
32namespace art {
33
34static mirror::Class* DecodeClass(const ScopedFastNativeObjectAccess& soa, jobject java_class)
35    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
36  mirror::Class* c = soa.Decode<mirror::Class*>(java_class);
37  DCHECK(c != NULL);
38  DCHECK(c->IsClass());
39  // TODO: we could EnsureInitialized here, rather than on every reflective get/set or invoke .
40  // For now, we conservatively preserve the old dalvik behavior. A quick "IsInitialized" check
41  // every time probably doesn't make much difference to reflection performance anyway.
42  return c;
43}
44
45// "name" is in "binary name" format, e.g. "dalvik.system.Debug$1".
46static jclass Class_classForName(JNIEnv* env, jclass, jstring javaName, jboolean initialize,
47                                 jobject javaLoader) {
48  ScopedFastNativeObjectAccess soa(env);
49  ScopedUtfChars name(env, javaName);
50  if (name.c_str() == nullptr) {
51    return nullptr;
52  }
53
54  // We need to validate and convert the name (from x.y.z to x/y/z).  This
55  // is especially handy for array types, since we want to avoid
56  // auto-generating bogus array classes.
57  if (!IsValidBinaryClassName(name.c_str())) {
58    soa.Self()->ThrowNewExceptionF("Ljava/lang/ClassNotFoundException;",
59                                   "Invalid name: %s", name.c_str());
60    return nullptr;
61  }
62
63  std::string descriptor(DotToDescriptor(name.c_str()));
64  StackHandleScope<2> hs(soa.Self());
65  Handle<mirror::ClassLoader> class_loader(hs.NewHandle(soa.Decode<mirror::ClassLoader*>(javaLoader)));
66  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
67  Handle<mirror::Class> c(
68      hs.NewHandle(class_linker->FindClass(soa.Self(), descriptor.c_str(), class_loader)));
69  if (c.Get() == nullptr) {
70    ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred());
71    env->ExceptionClear();
72    jthrowable cnfe = reinterpret_cast<jthrowable>(env->NewObject(WellKnownClasses::java_lang_ClassNotFoundException,
73                                                                  WellKnownClasses::java_lang_ClassNotFoundException_init,
74                                                                  javaName, cause.get()));
75    if (cnfe != nullptr) {
76      // Make sure allocation didn't fail with an OOME.
77      env->Throw(cnfe);
78    }
79    return nullptr;
80  }
81  if (initialize) {
82    class_linker->EnsureInitialized(soa.Self(), c, true, true);
83  }
84  return soa.AddLocalReference<jclass>(c.Get());
85}
86
87static jstring Class_getNameNative(JNIEnv* env, jobject javaThis) {
88  ScopedFastNativeObjectAccess soa(env);
89  StackHandleScope<1> hs(soa.Self());
90  mirror::Class* const c = DecodeClass(soa, javaThis);
91  return soa.AddLocalReference<jstring>(mirror::Class::ComputeName(hs.NewHandle(c)));
92}
93
94static jobjectArray Class_getProxyInterfaces(JNIEnv* env, jobject javaThis) {
95  ScopedFastNativeObjectAccess soa(env);
96  mirror::Class* c = DecodeClass(soa, javaThis);
97  return soa.AddLocalReference<jobjectArray>(c->GetInterfaces()->Clone(soa.Self()));
98}
99
100static JNINativeMethod gMethods[] = {
101  NATIVE_METHOD(Class, classForName, "!(Ljava/lang/String;ZLjava/lang/ClassLoader;)Ljava/lang/Class;"),
102  NATIVE_METHOD(Class, getNameNative, "!()Ljava/lang/String;"),
103  NATIVE_METHOD(Class, getProxyInterfaces, "!()[Ljava/lang/Class;"),
104};
105
106void register_java_lang_Class(JNIEnv* env) {
107  REGISTER_NATIVE_METHODS("java/lang/Class");
108}
109
110}  // namespace art
111