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