blob: 6cf7a2c82fb55c73e83ce5cf17cedc3f4ae21dfa [file] [log] [blame]
/*
* 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 "jni_internal.h"
#include "class_linker.h"
#include "class_loader.h"
#include "object.h"
#include "object_utils.h"
#include "ScopedLocalRef.h"
#include "ScopedUtfChars.h"
#include "JniConstants.h" // Last to avoid problems with LOG redefinition.
namespace art {
static Class* DecodeClass(JNIEnv* env, jobject java_class) {
Class* c = Decode<Class*>(env, java_class);
DCHECK(c != NULL);
DCHECK(c->IsClass());
// TODO: we could EnsureInitialized here, rather than on every reflective get/set or invoke .
// For now, we conservatively preserve the old dalvik behavior. A quick "IsInitialized" check
// every time probably doesn't make much difference to reflection performance anyway.
return c;
}
// "name" is in "binary name" format, e.g. "dalvik.system.Debug$1".
static jclass Class_classForName(JNIEnv* env, jclass, jstring javaName, jboolean initialize, jobject javaLoader) {
ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
ScopedUtfChars name(env, javaName);
if (name.c_str() == NULL) {
return NULL;
}
// We need to validate and convert the name (from x.y.z to x/y/z). This
// is especially handy for array types, since we want to avoid
// auto-generating bogus array classes.
if (!IsValidBinaryClassName(name.c_str())) {
Thread::Current()->ThrowNewExceptionF("Ljava/lang/ClassNotFoundException;",
"Invalid name: %s", name.c_str());
return NULL;
}
std::string descriptor(DotToDescriptor(name.c_str()));
Object* loader = Decode<Object*>(env, javaLoader);
ClassLoader* class_loader = down_cast<ClassLoader*>(loader);
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
Class* c = class_linker->FindClass(descriptor.c_str(), class_loader);
if (c == NULL) {
ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred());
env->ExceptionClear();
static jclass ClassNotFoundException_class = CacheClass(env, "java/lang/ClassNotFoundException");
static jmethodID ctor = env->GetMethodID(ClassNotFoundException_class, "<init>", "(Ljava/lang/String;Ljava/lang/Throwable;)V");
jthrowable cnfe = reinterpret_cast<jthrowable>(env->NewObject(ClassNotFoundException_class, ctor, javaName, cause.get()));
env->Throw(cnfe);
return NULL;
}
if (initialize) {
class_linker->EnsureInitialized(c, true);
}
return AddLocalReference<jclass>(env, c);
}
static jint Class_getAnnotationDirectoryOffset(JNIEnv* env, jclass javaClass) {
Class* c = DecodeClass(env, javaClass);
if (c->IsPrimitive() || c->IsArrayClass() || c->IsProxyClass()) {
return 0; // primitive, array and proxy classes don't have class definitions
}
const DexFile::ClassDef* class_def = ClassHelper(c).GetClassDef();
if (class_def == NULL) {
return 0; // not found
} else {
return class_def->annotations_off_;
}
}
template<typename T>
static jobjectArray ToArray(JNIEnv* env, const char* array_class_name, const std::vector<T*>& objects) {
jclass array_class = env->FindClass(array_class_name);
jobjectArray result = env->NewObjectArray(objects.size(), array_class, NULL);
for (size_t i = 0; i < objects.size(); ++i) {
ScopedLocalRef<jobject> object(env, AddLocalReference<jobject>(env, objects[i]));
env->SetObjectArrayElement(result, i, object.get());
}
return result;
}
static bool IsVisibleConstructor(Method* m, bool public_only) {
if (public_only && !m->IsPublic()) {
return false;
}
if (m->IsStatic()) {
return false;
}
return m->IsConstructor();
}
static jobjectArray Class_getDeclaredConstructors(JNIEnv* env, jclass javaClass, jboolean publicOnly) {
Class* c = DecodeClass(env, javaClass);
if (c == NULL) {
return NULL;
}
std::vector<Method*> constructors;
for (size_t i = 0; i < c->NumDirectMethods(); ++i) {
Method* m = c->GetDirectMethod(i);
if (IsVisibleConstructor(m, publicOnly)) {
constructors.push_back(m);
}
}
return ToArray(env, "java/lang/reflect/Constructor", constructors);
}
static bool IsVisibleField(Field* f, bool public_only) {
if (public_only && !f->IsPublic()) {
return false;
}
return true;
}
static jobjectArray Class_getDeclaredFields(JNIEnv* env, jclass javaClass, jboolean publicOnly) {
Class* c = DecodeClass(env, javaClass);
if (c == NULL) {
return NULL;
}
std::vector<Field*> fields;
FieldHelper fh;
for (size_t i = 0; i < c->NumInstanceFields(); ++i) {
Field* f = c->GetInstanceField(i);
fh.ChangeField(f);
if (IsVisibleField(f, publicOnly)) {
if (fh.GetType() == NULL) {
DCHECK(env->ExceptionOccurred());
return NULL;
}
fields.push_back(f);
}
if (env->ExceptionOccurred()) {
return NULL;
}
}
for (size_t i = 0; i < c->NumStaticFields(); ++i) {
Field* f = c->GetStaticField(i);
fh.ChangeField(f);
if (IsVisibleField(f, publicOnly)) {
if (fh.GetType() == NULL) {
DCHECK(env->ExceptionOccurred());
return NULL;
}
fields.push_back(f);
}
if (env->ExceptionOccurred()) {
return NULL;
}
}
return ToArray(env, "java/lang/reflect/Field", fields);
}
static bool IsVisibleMethod(Method* m, bool public_only) {
if (public_only && !m->IsPublic()) {
return false;
}
if (m->IsConstructor()) {
return false;
}
if (m->IsMiranda()) {
return false;
}
return true;
}
static jobjectArray Class_getDeclaredMethods(JNIEnv* env, jclass javaClass, jboolean publicOnly) {
ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
Class* c = DecodeClass(env, javaClass);
if (c == NULL) {
return NULL;
}
std::vector<Method*> methods;
MethodHelper mh;
for (size_t i = 0; i < c->NumVirtualMethods(); ++i) {
Method* m = c->GetVirtualMethod(i);
mh.ChangeMethod(m);
if (IsVisibleMethod(m, publicOnly)) {
if (mh.GetReturnType() == NULL || mh.GetParameterTypes() == NULL) {
DCHECK(env->ExceptionOccurred());
return NULL;
}
methods.push_back(m);
}
if (env->ExceptionOccurred()) {
return NULL;
}
}
for (size_t i = 0; i < c->NumDirectMethods(); ++i) {
Method* m = c->GetDirectMethod(i);
mh.ChangeMethod(m);
if (IsVisibleMethod(m, publicOnly)) {
if (mh.GetReturnType() == NULL || mh.GetParameterTypes() == NULL) {
DCHECK(env->ExceptionOccurred());
return NULL;
}
methods.push_back(m);
}
if (env->ExceptionOccurred()) {
return NULL;
}
}
return ToArray(env, "java/lang/reflect/Method", methods);
}
static jobject Class_getDex(JNIEnv* env, jobject javaClass) {
Class* c = DecodeClass(env, javaClass);
DexCache* dex_cache = c->GetDexCache();
if (dex_cache == NULL) {
return NULL;
}
return Runtime::Current()->GetClassLinker()->FindDexFile(dex_cache).GetDexObject(env);
}
static bool MethodMatches(MethodHelper* mh, const std::string& name, ObjectArray<Class>* arg_array) {
if (name != mh->GetName()) {
return false;
}
const DexFile::TypeList* m_type_list = mh->GetParameterTypeList();
uint32_t m_type_list_size = m_type_list == NULL ? 0 : m_type_list->Size();
uint32_t sig_length = arg_array->GetLength();
if (m_type_list_size != sig_length) {
return false;
}
for (uint32_t i = 0; i < sig_length; i++) {
if (mh->GetClassFromTypeIdx(m_type_list->GetTypeItem(i).type_idx_) != arg_array->Get(i)) {
return false;
}
}
return true;
}
static Method* FindConstructorOrMethodInArray(ObjectArray<Method>* methods, const std::string& name,
ObjectArray<Class>* arg_array) {
if (methods == NULL) {
return NULL;
}
Method* result = NULL;
MethodHelper mh;
for (int32_t i = 0; i < methods->GetLength(); ++i) {
Method* method = methods->Get(i);
mh.ChangeMethod(method);
if (method->IsMiranda() || !MethodMatches(&mh, name, arg_array)) {
continue;
}
result = method;
// Covariant return types permit the class to define multiple
// methods with the same name and parameter types. Prefer to return
// a non-synthetic method in such situations. We may still return
// a synthetic method to handle situations like escalated visibility.
if (!method->IsSynthetic()) {
break;
}
}
return result;
}
static jobject Class_getDeclaredConstructorOrMethod(JNIEnv* env, jclass javaClass, jstring javaName,
jobjectArray javaArgs) {
Class* c = DecodeClass(env, javaClass);
if (c == NULL) {
return NULL;
}
std::string name(Decode<String*>(env, javaName)->ToModifiedUtf8());
ObjectArray<Class>* arg_array = Decode<ObjectArray<Class>*>(env, javaArgs);
Method* m = FindConstructorOrMethodInArray(c->GetDirectMethods(), name, arg_array);
if (m == NULL) {
m = FindConstructorOrMethodInArray(c->GetVirtualMethods(), name, arg_array);
}
if (m != NULL) {
return AddLocalReference<jobject>(env, m);
} else {
return NULL;
}
}
static jobject Class_getDeclaredFieldNative(JNIEnv* env, jclass java_class, jobject jname) {
ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
Class* c = DecodeClass(env, java_class);
if (c == NULL) {
return NULL;
}
String* name = Decode<String*>(env, jname);
DCHECK(name->GetClass()->IsStringClass());
FieldHelper fh;
for (size_t i = 0; i < c->NumInstanceFields(); ++i) {
Field* f = c->GetInstanceField(i);
fh.ChangeField(f);
if (name->Equals(fh.GetName())) {
if (fh.GetType() == NULL) {
DCHECK(env->ExceptionOccurred());
return NULL;
}
return AddLocalReference<jclass>(env, f);
}
}
for (size_t i = 0; i < c->NumStaticFields(); ++i) {
Field* f = c->GetStaticField(i);
fh.ChangeField(f);
if (name->Equals(fh.GetName())) {
if (fh.GetType() == NULL) {
DCHECK(env->ExceptionOccurred());
return NULL;
}
return AddLocalReference<jclass>(env, f);
}
}
return NULL;
}
static jstring Class_getNameNative(JNIEnv* env, jobject javaThis) {
ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
Class* c = DecodeClass(env, javaThis);
return AddLocalReference<jstring>(env, c->ComputeName());
}
static jobjectArray Class_getProxyInterfaces(JNIEnv* env, jobject javaThis) {
ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
SynthesizedProxyClass* c = down_cast<SynthesizedProxyClass*>(DecodeClass(env, javaThis));
return AddLocalReference<jobjectArray>(env, c->GetInterfaces()->Clone());
}
static jboolean Class_isAssignableFrom(JNIEnv* env, jobject javaLhs, jclass javaRhs) {
ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
Class* lhs = DecodeClass(env, javaLhs);
Class* rhs = Decode<Class*>(env, javaRhs); // Can be null.
if (rhs == NULL) {
Thread::Current()->ThrowNewException("Ljava/lang/NullPointerException;", "class == null");
return JNI_FALSE;
}
return lhs->IsAssignableFrom(rhs) ? JNI_TRUE : JNI_FALSE;
}
static jboolean Class_isInstance(JNIEnv* env, jobject javaClass, jobject javaObject) {
Class* c = DecodeClass(env, javaClass);
Object* o = Decode<Object*>(env, javaObject);
if (o == NULL) {
return JNI_FALSE;
}
return o->InstanceOf(c) ? JNI_TRUE : JNI_FALSE;
}
// Validate method/field access.
static bool CheckMemberAccess(const Class* access_from, Class* access_to, uint32_t member_flags) {
// quick accept for public access */
if (member_flags & kAccPublic) {
return true;
}
// quick accept for access from same class
if (access_from == access_to) {
return true;
}
// quick reject for private access from another class
if (member_flags & kAccPrivate) {
return false;
}
// Semi-quick test for protected access from a sub-class, which may or
// may not be in the same package.
if (member_flags & kAccProtected) {
if (access_from->IsSubClass(access_to)) {
return true;
}
}
// Allow protected and private access from other classes in the same
return access_from->IsInSamePackage(access_to);
}
static jobject Class_newInstanceImpl(JNIEnv* env, jobject javaThis) {
ScopedThreadStateChange tsc(Thread::Current(), Thread::kRunnable);
Class* c = DecodeClass(env, javaThis);
if (c->IsPrimitive() || c->IsInterface() || c->IsArrayClass() || c->IsAbstract()) {
Thread::Current()->ThrowNewExceptionF("Ljava/lang/InstantiationException;",
"Class %s can not be instantiated", PrettyDescriptor(ClassHelper(c).GetDescriptor()).c_str());
return NULL;
}
if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(c, true)) {
return NULL;
}
Method* init = c->FindDeclaredDirectMethod("<init>", "()V");
if (init == NULL) {
Thread::Current()->ThrowNewExceptionF("Ljava/lang/InstantiationException;",
"Class %s has no default <init>()V constructor", PrettyDescriptor(ClassHelper(c).GetDescriptor()).c_str());
return NULL;
}
// Verify access from the call site.
//
// First, make sure the method invoking Class.newInstance() has permission
// to access the class.
//
// Second, make sure it has permission to invoke the constructor. The
// constructor must be public or, if the caller is in the same package,
// have package scope.
// TODO: need SmartFrame (Thread::WalkStack-like iterator).
Frame frame = Thread::Current()->GetTopOfStack();
frame.Next();
frame.Next();
Method* caller_caller = frame.GetMethod();
Class* caller_class = caller_caller->GetDeclaringClass();
ClassHelper caller_ch(caller_class);
if (!caller_class->CanAccess(c)) {
Thread::Current()->ThrowNewExceptionF("Ljava/lang/IllegalAccessException;",
"Class %s is not accessible from class %s",
PrettyDescriptor(ClassHelper(c).GetDescriptor()).c_str(),
PrettyDescriptor(caller_ch.GetDescriptor()).c_str());
return NULL;
}
if (!CheckMemberAccess(caller_class, init->GetDeclaringClass(), init->GetAccessFlags())) {
Thread::Current()->ThrowNewExceptionF("Ljava/lang/IllegalAccessException;",
"%s is not accessible from class %s",
PrettyMethod(init).c_str(),
PrettyDescriptor(caller_ch.GetDescriptor()).c_str());
return NULL;
}
Object* new_obj = c->AllocObject();
if (new_obj == NULL) {
DCHECK(Thread::Current()->IsExceptionPending());
return NULL;
}
// invoke constructor; unlike reflection calls, we don't wrap exceptions
jclass java_class = AddLocalReference<jclass>(env, c);
jmethodID mid = EncodeMethod(init);
return env->NewObject(java_class, mid);
}
static JNINativeMethod gMethods[] = {
NATIVE_METHOD(Class, classForName, "(Ljava/lang/String;ZLjava/lang/ClassLoader;)Ljava/lang/Class;"),
NATIVE_METHOD(Class, getAnnotationDirectoryOffset, "()I"),
NATIVE_METHOD(Class, getDeclaredConstructorOrMethod, "(Ljava/lang/String;[Ljava/lang/Class;)Ljava/lang/reflect/Member;"),
NATIVE_METHOD(Class, getDeclaredConstructors, "(Z)[Ljava/lang/reflect/Constructor;"),
NATIVE_METHOD(Class, getDeclaredFieldNative, "(Ljava/lang/String;)Ljava/lang/reflect/Field;"),
NATIVE_METHOD(Class, getDeclaredFields, "(Z)[Ljava/lang/reflect/Field;"),
NATIVE_METHOD(Class, getDeclaredMethods, "(Z)[Ljava/lang/reflect/Method;"),
NATIVE_METHOD(Class, getDex, "()Lcom/android/dex/Dex;"),
NATIVE_METHOD(Class, getNameNative, "()Ljava/lang/String;"),
NATIVE_METHOD(Class, getProxyInterfaces, "()[Ljava/lang/Class;"),
NATIVE_METHOD(Class, isAssignableFrom, "(Ljava/lang/Class;)Z"),
NATIVE_METHOD(Class, isInstance, "(Ljava/lang/Object;)Z"),
NATIVE_METHOD(Class, newInstanceImpl, "()Ljava/lang/Object;"),
};
void register_java_lang_Class(JNIEnv* env) {
jniRegisterNativeMethods(env, "java/lang/Class", gMethods, NELEM(gMethods));
}
} // namespace art