java_lang_Class.cc revision 9837939678bb5dcba178e5fb00ed59b5d14c8d9b
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 "mirror/proxy.h"
25#include "object_utils.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  ScopedObjectAccess 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    ThrowLocation throw_location = soa.Self()->GetCurrentLocationForThrow();
59    soa.Self()->ThrowNewExceptionF(throw_location, "Ljava/lang/ClassNotFoundException;",
60                                   "Invalid name: %s", name.c_str());
61    return nullptr;
62  }
63
64  std::string descriptor(DotToDescriptor(name.c_str()));
65  SirtRef<mirror::ClassLoader> class_loader(soa.Self(),
66                                            soa.Decode<mirror::ClassLoader*>(javaLoader));
67  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
68  SirtRef<mirror::Class> c(soa.Self(), class_linker->FindClass(soa.Self(), descriptor.c_str(),
69                                                               class_loader));
70  if (c.get() == nullptr) {
71    ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred());
72    env->ExceptionClear();
73    jthrowable cnfe = reinterpret_cast<jthrowable>(env->NewObject(WellKnownClasses::java_lang_ClassNotFoundException,
74                                                                  WellKnownClasses::java_lang_ClassNotFoundException_init,
75                                                                  javaName, cause.get()));
76    env->Throw(cnfe);
77    return nullptr;
78  }
79  if (initialize) {
80    class_linker->EnsureInitialized(c, true, true);
81  }
82  return soa.AddLocalReference<jclass>(c.get());
83}
84
85static jstring Class_getNameNative(JNIEnv* env, jobject javaThis) {
86  ScopedFastNativeObjectAccess soa(env);
87  mirror::Class* c = DecodeClass(soa, javaThis);
88  return soa.AddLocalReference<jstring>(c->ComputeName());
89}
90
91static jobjectArray Class_getProxyInterfaces(JNIEnv* env, jobject javaThis) {
92  ScopedFastNativeObjectAccess soa(env);
93  mirror::SynthesizedProxyClass* c =
94      down_cast<mirror::SynthesizedProxyClass*>(DecodeClass(soa, javaThis));
95  return soa.AddLocalReference<jobjectArray>(c->GetInterfaces()->Clone(soa.Self()));
96}
97
98static JNINativeMethod gMethods[] = {
99  NATIVE_METHOD(Class, classForName, "(Ljava/lang/String;ZLjava/lang/ClassLoader;)Ljava/lang/Class;"),
100  NATIVE_METHOD(Class, getNameNative, "!()Ljava/lang/String;"),
101  NATIVE_METHOD(Class, getProxyInterfaces, "!()[Ljava/lang/Class;"),
102};
103
104void register_java_lang_Class(JNIEnv* env) {
105  REGISTER_NATIVE_METHODS("java/lang/Class");
106}
107
108}  // namespace art
109