1 /*
2 * Copyright (C) 2016 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_reflect_Parameter.h"
18
19 #include "android-base/stringprintf.h"
20 #include "nativehelper/jni_macros.h"
21
22 #include "art_method-inl.h"
23 #include "base/utils.h"
24 #include "common_throws.h"
25 #include "dex/dex_file-inl.h"
26 #include "dex/dex_file_annotations.h"
27 #include "jni/jni_internal.h"
28 #include "native_util.h"
29 #include "scoped_fast_native_object_access-inl.h"
30
31 namespace art {
32
33 using android::base::StringPrintf;
34
Parameter_getAnnotationNative(JNIEnv * env,jclass,jobject javaMethod,jint parameterIndex,jclass annotationType)35 static jobject Parameter_getAnnotationNative(JNIEnv* env,
36 jclass,
37 jobject javaMethod,
38 jint parameterIndex,
39 jclass annotationType) {
40 ScopedFastNativeObjectAccess soa(env);
41 if (UNLIKELY(javaMethod == nullptr)) {
42 ThrowNullPointerException("javaMethod == null");
43 return nullptr;
44 }
45
46 ArtMethod* method = ArtMethod::FromReflectedMethod(soa, javaMethod);
47 if (method->IsProxyMethod()) {
48 return nullptr;
49 }
50
51 uint32_t parameter_count = method->GetParameterTypeList()->Size();
52 if (UNLIKELY(parameterIndex < 0 || static_cast<uint32_t>(parameterIndex) >= parameter_count)) {
53 ThrowIllegalArgumentException(
54 StringPrintf("Illegal parameterIndex %d for %s, parameter_count is %d",
55 parameterIndex,
56 method->PrettyMethod().c_str(),
57 parameter_count).c_str());
58 return nullptr;
59 }
60
61 uint32_t annotated_parameter_count = annotations::GetNumberOfAnnotatedMethodParameters(method);
62 if (annotated_parameter_count == 0u) {
63 return nullptr;
64 }
65
66 // For constructors with implicit arguments, we may need to adjust
67 // annotation positions based on whether the implicit parameters are
68 // expected to known and not just a compiler implementation detail.
69 if (method->IsConstructor()) {
70 StackHandleScope<1> hs(soa.Self());
71 // If declaring class is a local or an enum, do not pad parameter
72 // annotations, as the implicit constructor parameters are an
73 // implementation detail rather than required by JLS.
74 Handle<mirror::Class> declaring_class = hs.NewHandle(method->GetDeclaringClass());
75 if (annotations::GetEnclosingMethod(declaring_class) == nullptr && !declaring_class->IsEnum()) {
76 // Adjust the parameter index if the number of annotations does
77 // not match the number of parameters.
78 if (annotated_parameter_count <= parameter_count) {
79 // Workaround for dexer not inserting annotation state for implicit parameters (b/68033708).
80 uint32_t skip_count = parameter_count - annotated_parameter_count;
81 DCHECK_GE(2u, skip_count);
82 if (parameterIndex < static_cast<jint>(skip_count)) {
83 return nullptr;
84 }
85 parameterIndex -= skip_count;
86 } else {
87 // Workaround for Jack erroneously inserting implicit parameter for local classes
88 // (b/68033708).
89 DCHECK_EQ(1u, annotated_parameter_count - parameter_count);
90 parameterIndex += static_cast<jint>(annotated_parameter_count - parameter_count);
91 }
92 }
93 }
94
95 StackHandleScope<1> hs(soa.Self());
96 Handle<mirror::Class> klass(hs.NewHandle(soa.Decode<mirror::Class>(annotationType)));
97 return soa.AddLocalReference<jobject>(
98 annotations::GetAnnotationForMethodParameter(method, parameterIndex, klass));
99 }
100
101 static JNINativeMethod gMethods[] = {
102 FAST_NATIVE_METHOD(
103 Parameter,
104 getAnnotationNative,
105 "(Ljava/lang/reflect/Executable;ILjava/lang/Class;)Ljava/lang/annotation/Annotation;"),
106 };
107
register_java_lang_reflect_Parameter(JNIEnv * env)108 void register_java_lang_reflect_Parameter(JNIEnv* env) {
109 REGISTER_NATIVE_METHODS("java/lang/reflect/Parameter");
110 }
111
112 } // namespace art
113