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 <iostream>
20
21#include "art_field-inl.h"
22#include "class_linker.h"
23#include "common_throws.h"
24#include "dex_file-inl.h"
25#include "jni_internal.h"
26#include "nth_caller_visitor.h"
27#include "mirror/class-inl.h"
28#include "mirror/class_loader.h"
29#include "mirror/field-inl.h"
30#include "mirror/method.h"
31#include "mirror/object-inl.h"
32#include "mirror/object_array-inl.h"
33#include "mirror/string-inl.h"
34#include "reflection.h"
35#include "scoped_thread_state_change.h"
36#include "scoped_fast_native_object_access.h"
37#include "ScopedLocalRef.h"
38#include "ScopedUtfChars.h"
39#include "utf.h"
40#include "well_known_classes.h"
41
42namespace art {
43
44ALWAYS_INLINE static inline mirror::Class* DecodeClass(
45    const ScopedFastNativeObjectAccess& soa, jobject java_class)
46    SHARED_REQUIRES(Locks::mutator_lock_) {
47  mirror::Class* c = soa.Decode<mirror::Class*>(java_class);
48  DCHECK(c != nullptr);
49  DCHECK(c->IsClass());
50  // TODO: we could EnsureInitialized here, rather than on every reflective get/set or invoke .
51  // For now, we conservatively preserve the old dalvik behavior. A quick "IsInitialized" check
52  // every time probably doesn't make much difference to reflection performance anyway.
53  return c;
54}
55
56// "name" is in "binary name" format, e.g. "dalvik.system.Debug$1".
57static jclass Class_classForName(JNIEnv* env, jclass, jstring javaName, jboolean initialize,
58                                 jobject javaLoader) {
59  ScopedFastNativeObjectAccess soa(env);
60  ScopedUtfChars name(env, javaName);
61  if (name.c_str() == nullptr) {
62    return nullptr;
63  }
64
65  // We need to validate and convert the name (from x.y.z to x/y/z).  This
66  // is especially handy for array types, since we want to avoid
67  // auto-generating bogus array classes.
68  if (!IsValidBinaryClassName(name.c_str())) {
69    soa.Self()->ThrowNewExceptionF("Ljava/lang/ClassNotFoundException;",
70                                   "Invalid name: %s", name.c_str());
71    return nullptr;
72  }
73
74  std::string descriptor(DotToDescriptor(name.c_str()));
75  StackHandleScope<2> hs(soa.Self());
76  Handle<mirror::ClassLoader> class_loader(hs.NewHandle(soa.Decode<mirror::ClassLoader*>(javaLoader)));
77  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
78  Handle<mirror::Class> c(
79      hs.NewHandle(class_linker->FindClass(soa.Self(), descriptor.c_str(), class_loader)));
80  if (c.Get() == nullptr) {
81    ScopedLocalRef<jthrowable> cause(env, env->ExceptionOccurred());
82    env->ExceptionClear();
83    jthrowable cnfe = reinterpret_cast<jthrowable>(env->NewObject(WellKnownClasses::java_lang_ClassNotFoundException,
84                                                                  WellKnownClasses::java_lang_ClassNotFoundException_init,
85                                                                  javaName, cause.get()));
86    if (cnfe != nullptr) {
87      // Make sure allocation didn't fail with an OOME.
88      env->Throw(cnfe);
89    }
90    return nullptr;
91  }
92  if (initialize) {
93    class_linker->EnsureInitialized(soa.Self(), c, true, true);
94  }
95  return soa.AddLocalReference<jclass>(c.Get());
96}
97
98static jstring Class_getNameNative(JNIEnv* env, jobject javaThis) {
99  ScopedFastNativeObjectAccess soa(env);
100  StackHandleScope<1> hs(soa.Self());
101  mirror::Class* const c = DecodeClass(soa, javaThis);
102  return soa.AddLocalReference<jstring>(mirror::Class::ComputeName(hs.NewHandle(c)));
103}
104
105static jobjectArray Class_getProxyInterfaces(JNIEnv* env, jobject javaThis) {
106  ScopedFastNativeObjectAccess soa(env);
107  mirror::Class* c = DecodeClass(soa, javaThis);
108  return soa.AddLocalReference<jobjectArray>(c->GetInterfaces()->Clone(soa.Self()));
109}
110
111static mirror::ObjectArray<mirror::Field>* GetDeclaredFields(
112    Thread* self, mirror::Class* klass, bool public_only, bool force_resolve)
113      SHARED_REQUIRES(Locks::mutator_lock_) {
114  StackHandleScope<1> hs(self);
115  IterationRange<StrideIterator<ArtField>> ifields = klass->GetIFields();
116  IterationRange<StrideIterator<ArtField>> sfields = klass->GetSFields();
117  size_t array_size = klass->NumInstanceFields() + klass->NumStaticFields();
118  if (public_only) {
119    // Lets go subtract all the non public fields.
120    for (ArtField& field : ifields) {
121      if (!field.IsPublic()) {
122        --array_size;
123      }
124    }
125    for (ArtField& field : sfields) {
126      if (!field.IsPublic()) {
127        --array_size;
128      }
129    }
130  }
131  size_t array_idx = 0;
132  auto object_array = hs.NewHandle(mirror::ObjectArray<mirror::Field>::Alloc(
133      self, mirror::Field::ArrayClass(), array_size));
134  if (object_array.Get() == nullptr) {
135    return nullptr;
136  }
137  for (ArtField& field : ifields) {
138    if (!public_only || field.IsPublic()) {
139      auto* reflect_field = mirror::Field::CreateFromArtField(self, &field, force_resolve);
140      if (reflect_field == nullptr) {
141        if (kIsDebugBuild) {
142          self->AssertPendingException();
143        }
144        // Maybe null due to OOME or type resolving exception.
145        return nullptr;
146      }
147      object_array->SetWithoutChecks<false>(array_idx++, reflect_field);
148    }
149  }
150  for (ArtField& field : sfields) {
151    if (!public_only || field.IsPublic()) {
152      auto* reflect_field = mirror::Field::CreateFromArtField(self, &field, force_resolve);
153      if (reflect_field == nullptr) {
154        if (kIsDebugBuild) {
155          self->AssertPendingException();
156        }
157        return nullptr;
158      }
159      object_array->SetWithoutChecks<false>(array_idx++, reflect_field);
160    }
161  }
162  DCHECK_EQ(array_idx, array_size);
163  return object_array.Get();
164}
165
166static jobjectArray Class_getDeclaredFieldsUnchecked(JNIEnv* env, jobject javaThis,
167                                                     jboolean publicOnly) {
168  ScopedFastNativeObjectAccess soa(env);
169  return soa.AddLocalReference<jobjectArray>(
170      GetDeclaredFields(soa.Self(), DecodeClass(soa, javaThis), publicOnly != JNI_FALSE, false));
171}
172
173static jobjectArray Class_getDeclaredFields(JNIEnv* env, jobject javaThis) {
174  ScopedFastNativeObjectAccess soa(env);
175  return soa.AddLocalReference<jobjectArray>(
176      GetDeclaredFields(soa.Self(), DecodeClass(soa, javaThis), false, true));
177}
178
179static jobjectArray Class_getPublicDeclaredFields(JNIEnv* env, jobject javaThis) {
180  ScopedFastNativeObjectAccess soa(env);
181  return soa.AddLocalReference<jobjectArray>(
182      GetDeclaredFields(soa.Self(), DecodeClass(soa, javaThis), true, true));
183}
184
185// Performs a binary search through an array of fields, TODO: Is this fast enough if we don't use
186// the dex cache for lookups? I think CompareModifiedUtf8ToUtf16AsCodePointValues should be fairly
187// fast.
188ALWAYS_INLINE static inline ArtField* FindFieldByName(
189    Thread* self ATTRIBUTE_UNUSED, mirror::String* name, LengthPrefixedArray<ArtField>* fields)
190    SHARED_REQUIRES(Locks::mutator_lock_) {
191  if (fields == nullptr) {
192    return nullptr;
193  }
194  size_t low = 0;
195  size_t high = fields->size();
196  const uint16_t* const data = name->GetValue();
197  const size_t length = name->GetLength();
198  while (low < high) {
199    auto mid = (low + high) / 2;
200    ArtField& field = fields->At(mid);
201    int result = CompareModifiedUtf8ToUtf16AsCodePointValues(field.GetName(), data, length);
202    // Alternate approach, only a few % faster at the cost of more allocations.
203    // int result = field->GetStringName(self, true)->CompareTo(name);
204    if (result < 0) {
205      low = mid + 1;
206    } else if (result > 0) {
207      high = mid;
208    } else {
209      return &field;
210    }
211  }
212  if (kIsDebugBuild) {
213    for (ArtField& field : MakeIterationRangeFromLengthPrefixedArray(fields)) {
214      CHECK_NE(field.GetName(), name->ToModifiedUtf8());
215    }
216  }
217  return nullptr;
218}
219
220ALWAYS_INLINE static inline mirror::Field* GetDeclaredField(
221    Thread* self, mirror::Class* c, mirror::String* name)
222    SHARED_REQUIRES(Locks::mutator_lock_) {
223  ArtField* art_field = FindFieldByName(self, name, c->GetIFieldsPtr());
224  if (art_field != nullptr) {
225    return mirror::Field::CreateFromArtField(self, art_field, true);
226  }
227  art_field = FindFieldByName(self, name, c->GetSFieldsPtr());
228  if (art_field != nullptr) {
229    return mirror::Field::CreateFromArtField(self, art_field, true);
230  }
231  return nullptr;
232}
233
234static mirror::Field* GetPublicFieldRecursive(
235    Thread* self, mirror::Class* clazz, mirror::String* name)
236    SHARED_REQUIRES(Locks::mutator_lock_) {
237  DCHECK(clazz != nullptr);
238  DCHECK(name != nullptr);
239  DCHECK(self != nullptr);
240
241  StackHandleScope<2> hs(self);
242  MutableHandle<mirror::Class> h_clazz(hs.NewHandle(clazz));
243  Handle<mirror::String> h_name(hs.NewHandle(name));
244
245  // We search the current class, its direct interfaces then its superclass.
246  while (h_clazz.Get() != nullptr) {
247    mirror::Field* result = GetDeclaredField(self, h_clazz.Get(), h_name.Get());
248    if ((result != nullptr) && (result->GetAccessFlags() & kAccPublic)) {
249      return result;
250    } else if (UNLIKELY(self->IsExceptionPending())) {
251      // Something went wrong. Bail out.
252      return nullptr;
253    }
254
255    uint32_t num_direct_interfaces = h_clazz->NumDirectInterfaces();
256    for (uint32_t i = 0; i < num_direct_interfaces; i++) {
257      mirror::Class *iface = mirror::Class::GetDirectInterface(self, h_clazz, i);
258      if (UNLIKELY(iface == nullptr)) {
259        self->AssertPendingException();
260        return nullptr;
261      }
262      result = GetPublicFieldRecursive(self, iface, h_name.Get());
263      if (result != nullptr) {
264        DCHECK(result->GetAccessFlags() & kAccPublic);
265        return result;
266      } else if (UNLIKELY(self->IsExceptionPending())) {
267        // Something went wrong. Bail out.
268        return nullptr;
269      }
270    }
271
272    // We don't try the superclass if we are an interface.
273    if (h_clazz->IsInterface()) {
274      break;
275    }
276
277    // Get the next class.
278    h_clazz.Assign(h_clazz->GetSuperClass());
279  }
280  return nullptr;
281}
282
283static jobject Class_getPublicFieldRecursive(JNIEnv* env, jobject javaThis, jstring name) {
284  ScopedFastNativeObjectAccess soa(env);
285  auto* name_string = soa.Decode<mirror::String*>(name);
286  if (UNLIKELY(name_string == nullptr)) {
287    ThrowNullPointerException("name == null");
288    return nullptr;
289  }
290  return soa.AddLocalReference<jobject>(
291      GetPublicFieldRecursive(soa.Self(), DecodeClass(soa, javaThis), name_string));
292}
293
294static jobject Class_getDeclaredField(JNIEnv* env, jobject javaThis, jstring name) {
295  ScopedFastNativeObjectAccess soa(env);
296  auto* name_string = soa.Decode<mirror::String*>(name);
297  if (name_string == nullptr) {
298    ThrowNullPointerException("name == null");
299    return nullptr;
300  }
301  auto* klass = DecodeClass(soa, javaThis);
302  mirror::Field* result = GetDeclaredField(soa.Self(), klass, name_string);
303  if (result == nullptr) {
304    std::string name_str = name_string->ToModifiedUtf8();
305    if (name_str == "value" && klass->IsStringClass()) {
306      // We log the error for this specific case, as the user might just swallow the exception.
307      // This helps diagnose crashes when applications rely on the String#value field being
308      // there.
309      // Also print on the error stream to test it through run-test.
310      std::string message("The String#value field is not present on Android versions >= 6.0");
311      LOG(ERROR) << message;
312      std::cerr << message << std::endl;
313    }
314    // We may have a pending exception if we failed to resolve.
315    if (!soa.Self()->IsExceptionPending()) {
316      ThrowNoSuchFieldException(DecodeClass(soa, javaThis), name_str.c_str());
317    }
318    return nullptr;
319  }
320  return soa.AddLocalReference<jobject>(result);
321}
322
323static jobject Class_getDeclaredConstructorInternal(
324    JNIEnv* env, jobject javaThis, jobjectArray args) {
325  ScopedFastNativeObjectAccess soa(env);
326  mirror::Constructor* result = mirror::Class::GetDeclaredConstructorInternal(
327      soa.Self(),
328      DecodeClass(soa, javaThis),
329      soa.Decode<mirror::ObjectArray<mirror::Class>*>(args));
330  return soa.AddLocalReference<jobject>(result);
331}
332
333static ALWAYS_INLINE inline bool MethodMatchesConstructor(ArtMethod* m, bool public_only)
334    SHARED_REQUIRES(Locks::mutator_lock_) {
335  DCHECK(m != nullptr);
336  return (!public_only || m->IsPublic()) && !m->IsStatic() && m->IsConstructor();
337}
338
339static jobjectArray Class_getDeclaredConstructorsInternal(
340    JNIEnv* env, jobject javaThis, jboolean publicOnly) {
341  ScopedFastNativeObjectAccess soa(env);
342  StackHandleScope<2> hs(soa.Self());
343  Handle<mirror::Class> h_klass = hs.NewHandle(DecodeClass(soa, javaThis));
344  size_t constructor_count = 0;
345  // Two pass approach for speed.
346  for (auto& m : h_klass->GetDirectMethods(sizeof(void*))) {
347    constructor_count += MethodMatchesConstructor(&m, publicOnly != JNI_FALSE) ? 1u : 0u;
348  }
349  auto h_constructors = hs.NewHandle(mirror::ObjectArray<mirror::Constructor>::Alloc(
350      soa.Self(), mirror::Constructor::ArrayClass(), constructor_count));
351  if (UNLIKELY(h_constructors.Get() == nullptr)) {
352    soa.Self()->AssertPendingException();
353    return nullptr;
354  }
355  constructor_count = 0;
356  for (auto& m : h_klass->GetDirectMethods(sizeof(void*))) {
357    if (MethodMatchesConstructor(&m, publicOnly != JNI_FALSE)) {
358      auto* constructor = mirror::Constructor::CreateFromArtMethod(soa.Self(), &m);
359      if (UNLIKELY(constructor == nullptr)) {
360        soa.Self()->AssertPendingOOMException();
361        return nullptr;
362      }
363      h_constructors->SetWithoutChecks<false>(constructor_count++, constructor);
364    }
365  }
366  return soa.AddLocalReference<jobjectArray>(h_constructors.Get());
367}
368
369static jobject Class_getDeclaredMethodInternal(JNIEnv* env, jobject javaThis,
370                                               jobject name, jobjectArray args) {
371  ScopedFastNativeObjectAccess soa(env);
372  mirror::Method* result = mirror::Class::GetDeclaredMethodInternal(
373      soa.Self(),
374      DecodeClass(soa, javaThis),
375      soa.Decode<mirror::String*>(name),
376      soa.Decode<mirror::ObjectArray<mirror::Class>*>(args));
377  return soa.AddLocalReference<jobject>(result);
378}
379
380static jobjectArray Class_getDeclaredMethodsUnchecked(JNIEnv* env, jobject javaThis,
381                                                      jboolean publicOnly) {
382  ScopedFastNativeObjectAccess soa(env);
383  StackHandleScope<2> hs(soa.Self());
384  Handle<mirror::Class> klass = hs.NewHandle(DecodeClass(soa, javaThis));
385  size_t num_methods = 0;
386  for (auto& m : klass->GetDeclaredMethods(sizeof(void*))) {
387    auto modifiers = m.GetAccessFlags();
388    // Add non-constructor declared methods.
389    if ((publicOnly == JNI_FALSE || (modifiers & kAccPublic) != 0) &&
390        (modifiers & kAccConstructor) == 0) {
391      ++num_methods;
392    }
393  }
394  auto ret = hs.NewHandle(mirror::ObjectArray<mirror::Method>::Alloc(
395      soa.Self(), mirror::Method::ArrayClass(), num_methods));
396  num_methods = 0;
397  for (auto& m : klass->GetDeclaredMethods(sizeof(void*))) {
398    auto modifiers = m.GetAccessFlags();
399    if ((publicOnly == JNI_FALSE || (modifiers & kAccPublic) != 0) &&
400        (modifiers & kAccConstructor) == 0) {
401      auto* method = mirror::Method::CreateFromArtMethod(soa.Self(), &m);
402      if (method == nullptr) {
403        soa.Self()->AssertPendingException();
404        return nullptr;
405      }
406      ret->SetWithoutChecks<false>(num_methods++, method);
407    }
408  }
409  return soa.AddLocalReference<jobjectArray>(ret.Get());
410}
411
412static jobject Class_getDeclaredAnnotation(JNIEnv* env, jobject javaThis, jclass annotationClass) {
413  ScopedFastNativeObjectAccess soa(env);
414  StackHandleScope<2> hs(soa.Self());
415  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
416
417  // Handle public contract to throw NPE if the "annotationClass" argument was null.
418  if (UNLIKELY(annotationClass == nullptr)) {
419    ThrowNullPointerException("annotationClass");
420    return nullptr;
421  }
422
423  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
424    return nullptr;
425  }
426  Handle<mirror::Class> annotation_class(hs.NewHandle(soa.Decode<mirror::Class*>(annotationClass)));
427  return soa.AddLocalReference<jobject>(
428      klass->GetDexFile().GetAnnotationForClass(klass, annotation_class));
429}
430
431static jobjectArray Class_getDeclaredAnnotations(JNIEnv* env, jobject javaThis) {
432  ScopedFastNativeObjectAccess soa(env);
433  StackHandleScope<1> hs(soa.Self());
434  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
435  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
436    // Return an empty array instead of a null pointer.
437    mirror::Class* annotation_array_class =
438        soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_annotation_Annotation__array);
439    mirror::ObjectArray<mirror::Object>* empty_array =
440        mirror::ObjectArray<mirror::Object>::Alloc(soa.Self(), annotation_array_class, 0);
441    return soa.AddLocalReference<jobjectArray>(empty_array);
442  }
443  return soa.AddLocalReference<jobjectArray>(klass->GetDexFile().GetAnnotationsForClass(klass));
444}
445
446static jobjectArray Class_getDeclaredClasses(JNIEnv* env, jobject javaThis) {
447  ScopedFastNativeObjectAccess soa(env);
448  StackHandleScope<1> hs(soa.Self());
449  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
450  mirror::ObjectArray<mirror::Class>* classes = nullptr;
451  if (!klass->IsProxyClass() && klass->GetDexCache() != nullptr) {
452    classes = klass->GetDexFile().GetDeclaredClasses(klass);
453  }
454  if (classes == nullptr) {
455    // Return an empty array instead of a null pointer.
456    if (soa.Self()->IsExceptionPending()) {
457      // Pending exception from GetDeclaredClasses.
458      return nullptr;
459    }
460    mirror::Class* class_class = mirror::Class::GetJavaLangClass();
461    mirror::Class* class_array_class =
462        Runtime::Current()->GetClassLinker()->FindArrayClass(soa.Self(), &class_class);
463    if (class_array_class == nullptr) {
464      return nullptr;
465    }
466    mirror::ObjectArray<mirror::Class>* empty_array =
467        mirror::ObjectArray<mirror::Class>::Alloc(soa.Self(), class_array_class, 0);
468    return soa.AddLocalReference<jobjectArray>(empty_array);
469  }
470  return soa.AddLocalReference<jobjectArray>(classes);
471}
472
473static jclass Class_getEnclosingClass(JNIEnv* env, jobject javaThis) {
474  ScopedFastNativeObjectAccess soa(env);
475  StackHandleScope<1> hs(soa.Self());
476  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
477  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
478    return nullptr;
479  }
480  return soa.AddLocalReference<jclass>(klass->GetDexFile().GetEnclosingClass(klass));
481}
482
483static jobject Class_getEnclosingConstructorNative(JNIEnv* env, jobject javaThis) {
484  ScopedFastNativeObjectAccess soa(env);
485  StackHandleScope<1> hs(soa.Self());
486  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
487  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
488    return nullptr;
489  }
490  mirror::Object* method = klass->GetDexFile().GetEnclosingMethod(klass);
491  if (method != nullptr) {
492    if (method->GetClass() ==
493        soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_reflect_Constructor)) {
494      return soa.AddLocalReference<jobject>(method);
495    }
496  }
497  return nullptr;
498}
499
500static jobject Class_getEnclosingMethodNative(JNIEnv* env, jobject javaThis) {
501  ScopedFastNativeObjectAccess soa(env);
502  StackHandleScope<1> hs(soa.Self());
503  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
504  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
505    return nullptr;
506  }
507  mirror::Object* method = klass->GetDexFile().GetEnclosingMethod(klass);
508  if (method != nullptr) {
509    if (method->GetClass() ==
510        soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_reflect_Method)) {
511      return soa.AddLocalReference<jobject>(method);
512    }
513  }
514  return nullptr;
515}
516
517static jint Class_getInnerClassFlags(JNIEnv* env, jobject javaThis, jint defaultValue) {
518  ScopedFastNativeObjectAccess soa(env);
519  StackHandleScope<1> hs(soa.Self());
520  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
521  return mirror::Class::GetInnerClassFlags(klass, defaultValue);
522}
523
524static jstring Class_getInnerClassName(JNIEnv* env, jobject javaThis) {
525  ScopedFastNativeObjectAccess soa(env);
526  StackHandleScope<1> hs(soa.Self());
527  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
528  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
529    return nullptr;
530  }
531  mirror::String* class_name = nullptr;
532  if (!klass->GetDexFile().GetInnerClass(klass, &class_name)) {
533    return nullptr;
534  }
535  return soa.AddLocalReference<jstring>(class_name);
536}
537
538static jobjectArray Class_getSignatureAnnotation(JNIEnv* env, jobject javaThis) {
539  ScopedFastNativeObjectAccess soa(env);
540  StackHandleScope<1> hs(soa.Self());
541  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
542  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
543    return nullptr;
544  }
545  return soa.AddLocalReference<jobjectArray>(
546      klass->GetDexFile().GetSignatureAnnotationForClass(klass));
547}
548
549static jboolean Class_isAnonymousClass(JNIEnv* env, jobject javaThis) {
550  ScopedFastNativeObjectAccess soa(env);
551  StackHandleScope<1> hs(soa.Self());
552  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
553  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
554    return false;
555  }
556  mirror::String* class_name = nullptr;
557  if (!klass->GetDexFile().GetInnerClass(klass, &class_name)) {
558    return false;
559  }
560  return class_name == nullptr;
561}
562
563static jboolean Class_isDeclaredAnnotationPresent(JNIEnv* env, jobject javaThis,
564                                                  jclass annotationType) {
565  ScopedFastNativeObjectAccess soa(env);
566  StackHandleScope<2> hs(soa.Self());
567  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
568  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
569    return false;
570  }
571  Handle<mirror::Class> annotation_class(hs.NewHandle(soa.Decode<mirror::Class*>(annotationType)));
572  return klass->GetDexFile().IsClassAnnotationPresent(klass, annotation_class);
573}
574
575static jclass Class_getDeclaringClass(JNIEnv* env, jobject javaThis) {
576  ScopedFastNativeObjectAccess soa(env);
577  StackHandleScope<1> hs(soa.Self());
578  Handle<mirror::Class> klass(hs.NewHandle(DecodeClass(soa, javaThis)));
579  if (klass->IsProxyClass() || klass->GetDexCache() == nullptr) {
580    return nullptr;
581  }
582  // Return null for anonymous classes.
583  if (Class_isAnonymousClass(env, javaThis)) {
584    return nullptr;
585  }
586  return soa.AddLocalReference<jclass>(klass->GetDexFile().GetDeclaringClass(klass));
587}
588
589static jobject Class_newInstance(JNIEnv* env, jobject javaThis) {
590  ScopedFastNativeObjectAccess soa(env);
591  StackHandleScope<4> hs(soa.Self());
592  Handle<mirror::Class> klass = hs.NewHandle(DecodeClass(soa, javaThis));
593  if (UNLIKELY(klass->GetPrimitiveType() != 0 || klass->IsInterface() || klass->IsArrayClass() ||
594               klass->IsAbstract())) {
595    soa.Self()->ThrowNewExceptionF("Ljava/lang/InstantiationException;",
596                                   "%s cannot be instantiated", PrettyClass(klass.Get()).c_str());
597    return nullptr;
598  }
599  auto caller = hs.NewHandle<mirror::Class>(nullptr);
600  // Verify that we can access the class.
601  if (!klass->IsPublic()) {
602    caller.Assign(GetCallingClass(soa.Self(), 1));
603    if (caller.Get() != nullptr && !caller->CanAccess(klass.Get())) {
604      soa.Self()->ThrowNewExceptionF(
605          "Ljava/lang/IllegalAccessException;", "%s is not accessible from %s",
606          PrettyClass(klass.Get()).c_str(), PrettyClass(caller.Get()).c_str());
607      return nullptr;
608    }
609  }
610  auto* constructor = klass->GetDeclaredConstructor(
611      soa.Self(),
612      ScopedNullHandle<mirror::ObjectArray<mirror::Class>>(),
613      sizeof(void*));
614  if (UNLIKELY(constructor == nullptr)) {
615    soa.Self()->ThrowNewExceptionF("Ljava/lang/InstantiationException;",
616                                   "%s has no zero argument constructor",
617                                   PrettyClass(klass.Get()).c_str());
618    return nullptr;
619  }
620  // Invoke the string allocator to return an empty string for the string class.
621  if (klass->IsStringClass()) {
622    gc::AllocatorType allocator_type = Runtime::Current()->GetHeap()->GetCurrentAllocator();
623    mirror::SetStringCountVisitor visitor(0);
624    mirror::Object* obj = mirror::String::Alloc<true>(soa.Self(), 0, allocator_type, visitor);
625    if (UNLIKELY(soa.Self()->IsExceptionPending())) {
626      return nullptr;
627    } else {
628      return soa.AddLocalReference<jobject>(obj);
629    }
630  }
631  auto receiver = hs.NewHandle(klass->AllocObject(soa.Self()));
632  if (UNLIKELY(receiver.Get() == nullptr)) {
633    soa.Self()->AssertPendingOOMException();
634    return nullptr;
635  }
636  // Verify that we can access the constructor.
637  auto* declaring_class = constructor->GetDeclaringClass();
638  if (!constructor->IsPublic()) {
639    if (caller.Get() == nullptr) {
640      caller.Assign(GetCallingClass(soa.Self(), 1));
641    }
642    if (UNLIKELY(caller.Get() != nullptr && !VerifyAccess(
643        soa.Self(), receiver.Get(), declaring_class, constructor->GetAccessFlags(),
644        caller.Get()))) {
645      soa.Self()->ThrowNewExceptionF(
646          "Ljava/lang/IllegalAccessException;", "%s is not accessible from %s",
647          PrettyMethod(constructor).c_str(), PrettyClass(caller.Get()).c_str());
648      return nullptr;
649    }
650  }
651  // Ensure that we are initialized.
652  if (UNLIKELY(!declaring_class->IsInitialized())) {
653    if (!Runtime::Current()->GetClassLinker()->EnsureInitialized(
654        soa.Self(), hs.NewHandle(declaring_class), true, true)) {
655      soa.Self()->AssertPendingException();
656      return nullptr;
657    }
658  }
659  // Invoke the constructor.
660  JValue result;
661  uint32_t args[1] = { static_cast<uint32_t>(reinterpret_cast<uintptr_t>(receiver.Get())) };
662  constructor->Invoke(soa.Self(), args, sizeof(args), &result, "V");
663  if (UNLIKELY(soa.Self()->IsExceptionPending())) {
664    return nullptr;
665  }
666  // Constructors are ()V methods, so we shouldn't touch the result of InvokeMethod.
667  return soa.AddLocalReference<jobject>(receiver.Get());
668}
669
670static JNINativeMethod gMethods[] = {
671  NATIVE_METHOD(Class, classForName,
672                "!(Ljava/lang/String;ZLjava/lang/ClassLoader;)Ljava/lang/Class;"),
673  NATIVE_METHOD(Class, getDeclaredAnnotation,
674                "!(Ljava/lang/Class;)Ljava/lang/annotation/Annotation;"),
675  NATIVE_METHOD(Class, getDeclaredAnnotations, "!()[Ljava/lang/annotation/Annotation;"),
676  NATIVE_METHOD(Class, getDeclaredClasses, "!()[Ljava/lang/Class;"),
677  NATIVE_METHOD(Class, getDeclaredConstructorInternal,
678                "!([Ljava/lang/Class;)Ljava/lang/reflect/Constructor;"),
679  NATIVE_METHOD(Class, getDeclaredConstructorsInternal, "!(Z)[Ljava/lang/reflect/Constructor;"),
680  NATIVE_METHOD(Class, getDeclaredField, "!(Ljava/lang/String;)Ljava/lang/reflect/Field;"),
681  NATIVE_METHOD(Class, getPublicFieldRecursive, "!(Ljava/lang/String;)Ljava/lang/reflect/Field;"),
682  NATIVE_METHOD(Class, getDeclaredFields, "!()[Ljava/lang/reflect/Field;"),
683  NATIVE_METHOD(Class, getDeclaredFieldsUnchecked, "!(Z)[Ljava/lang/reflect/Field;"),
684  NATIVE_METHOD(Class, getDeclaredMethodInternal,
685                "!(Ljava/lang/String;[Ljava/lang/Class;)Ljava/lang/reflect/Method;"),
686  NATIVE_METHOD(Class, getDeclaredMethodsUnchecked,
687                "!(Z)[Ljava/lang/reflect/Method;"),
688  NATIVE_METHOD(Class, getDeclaringClass, "!()Ljava/lang/Class;"),
689  NATIVE_METHOD(Class, getEnclosingClass, "!()Ljava/lang/Class;"),
690  NATIVE_METHOD(Class, getEnclosingConstructorNative, "!()Ljava/lang/reflect/Constructor;"),
691  NATIVE_METHOD(Class, getEnclosingMethodNative, "!()Ljava/lang/reflect/Method;"),
692  NATIVE_METHOD(Class, getInnerClassFlags, "!(I)I"),
693  NATIVE_METHOD(Class, getInnerClassName, "!()Ljava/lang/String;"),
694  NATIVE_METHOD(Class, getNameNative, "!()Ljava/lang/String;"),
695  NATIVE_METHOD(Class, getProxyInterfaces, "!()[Ljava/lang/Class;"),
696  NATIVE_METHOD(Class, getPublicDeclaredFields, "!()[Ljava/lang/reflect/Field;"),
697  NATIVE_METHOD(Class, getSignatureAnnotation, "!()[Ljava/lang/String;"),
698  NATIVE_METHOD(Class, isAnonymousClass, "!()Z"),
699  NATIVE_METHOD(Class, isDeclaredAnnotationPresent, "!(Ljava/lang/Class;)Z"),
700  NATIVE_METHOD(Class, newInstance, "!()Ljava/lang/Object;"),
701};
702
703void register_java_lang_Class(JNIEnv* env) {
704  REGISTER_NATIVE_METHODS("java/lang/Class");
705}
706
707}  // namespace art
708