1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
|
/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "java_lang_VMClassLoader.h"
#include "base/zip_archive.h"
#include "class_linker.h"
#include "dex/descriptors_names.h"
#include "dex/dex_file_loader.h"
#include "dex/utf.h"
#include "handle_scope-inl.h"
#include "jni/jni_internal.h"
#include "mirror/class_loader.h"
#include "mirror/object-inl.h"
#include "native_util.h"
#include "nativehelper/jni_macros.h"
#include "nativehelper/scoped_local_ref.h"
#include "nativehelper/scoped_utf_chars.h"
#include "obj_ptr.h"
#include "scoped_fast_native_object_access-inl.h"
#include "well_known_classes.h"
namespace art {
// A class so we can be friends with ClassLinker and access internal methods.
class VMClassLoader {
public:
static ObjPtr<mirror::Class> LookupClass(ClassLinker* cl,
Thread* self,
const char* descriptor,
size_t hash,
ObjPtr<mirror::ClassLoader> class_loader)
REQUIRES(!Locks::classlinker_classes_lock_)
REQUIRES_SHARED(Locks::mutator_lock_) {
return cl->LookupClass(self, descriptor, hash, class_loader);
}
static ObjPtr<mirror::Class> FindClassInPathClassLoader(ClassLinker* cl,
ScopedObjectAccessAlreadyRunnable& soa,
Thread* self,
const char* descriptor,
size_t hash,
Handle<mirror::ClassLoader> class_loader)
REQUIRES_SHARED(Locks::mutator_lock_) {
ObjPtr<mirror::Class> result;
if (cl->FindClassInBaseDexClassLoader(soa, self, descriptor, hash, class_loader, &result)) {
DCHECK(!self->IsExceptionPending());
return result;
}
if (self->IsExceptionPending()) {
self->ClearException();
}
return nullptr;
}
};
static jclass VMClassLoader_findLoadedClass(JNIEnv* env, jclass, jobject javaLoader,
jstring javaName) {
ScopedFastNativeObjectAccess soa(env);
ObjPtr<mirror::ClassLoader> loader = soa.Decode<mirror::ClassLoader>(javaLoader);
ScopedUtfChars name(env, javaName);
if (name.c_str() == nullptr) {
return nullptr;
}
ClassLinker* cl = Runtime::Current()->GetClassLinker();
// Compute hash once.
std::string descriptor(DotToDescriptor(name.c_str()));
const size_t descriptor_hash = ComputeModifiedUtf8Hash(descriptor.c_str());
ObjPtr<mirror::Class> c = VMClassLoader::LookupClass(cl,
soa.Self(),
descriptor.c_str(),
descriptor_hash,
loader);
if (c != nullptr && c->IsResolved()) {
return soa.AddLocalReference<jclass>(c);
}
// If class is erroneous, throw the earlier failure, wrapped in certain cases. See b/28787733.
if (c != nullptr && c->IsErroneous()) {
cl->ThrowEarlierClassFailure(c);
Thread* self = soa.Self();
ObjPtr<mirror::Class> iae_class =
self->DecodeJObject(WellKnownClasses::java_lang_IllegalAccessError)->AsClass();
ObjPtr<mirror::Class> ncdfe_class =
self->DecodeJObject(WellKnownClasses::java_lang_NoClassDefFoundError)->AsClass();
ObjPtr<mirror::Class> exception = self->GetException()->GetClass();
if (exception == iae_class || exception == ncdfe_class) {
self->ThrowNewWrappedException("Ljava/lang/ClassNotFoundException;",
c->PrettyDescriptor().c_str());
}
return nullptr;
}
// Hard-coded performance optimization: We know that all failed libcore calls to findLoadedClass
// are followed by a call to the the classloader to actually
// load the class.
if (loader != nullptr) {
// Try the common case.
StackHandleScope<1> hs(soa.Self());
c = VMClassLoader::FindClassInPathClassLoader(cl,
soa,
soa.Self(),
descriptor.c_str(),
descriptor_hash,
hs.NewHandle(loader));
if (c != nullptr) {
return soa.AddLocalReference<jclass>(c);
}
}
// The class wasn't loaded, yet, and our fast-path did not apply (e.g., we didn't understand the
// classloader chain).
return nullptr;
}
/*
* Returns an array of entries from the boot classpath that could contain resources.
*/
static jobjectArray VMClassLoader_getBootClassPathEntries(JNIEnv* env, jclass) {
const std::vector<const DexFile*>& path =
Runtime::Current()->GetClassLinker()->GetBootClassPath();
jobjectArray array =
env->NewObjectArray(path.size(), WellKnownClasses::java_lang_String, nullptr);
if (array == nullptr) {
DCHECK(env->ExceptionCheck());
return nullptr;
}
for (size_t i = 0; i < path.size(); ++i) {
const DexFile* dex_file = path[i];
// For multidex locations, e.g., x.jar!classes2.dex, we want to look into x.jar.
const std::string location(DexFileLoader::GetBaseLocation(dex_file->GetLocation()));
ScopedLocalRef<jstring> javaPath(env, env->NewStringUTF(location.c_str()));
if (javaPath.get() == nullptr) {
DCHECK(env->ExceptionCheck());
return nullptr;
}
env->SetObjectArrayElement(array, i, javaPath.get());
}
return array;
}
static JNINativeMethod gMethods[] = {
FAST_NATIVE_METHOD(VMClassLoader, findLoadedClass, "(Ljava/lang/ClassLoader;Ljava/lang/String;)Ljava/lang/Class;"),
NATIVE_METHOD(VMClassLoader, getBootClassPathEntries, "()[Ljava/lang/String;"),
};
void register_java_lang_VMClassLoader(JNIEnv* env) {
REGISTER_NATIVE_METHODS("java/lang/VMClassLoader");
}
} // namespace art
|
