array.cc revision 4f6ad8ab428038129b2d0d6c40b7fd625cca15e1 
1/*
2 * Copyright (C) 2011 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 "array.h"
18
19#include "class.h"
20#include "class-inl.h"
21#include "dex_file-inl.h"
22#include "gc/card_table-inl.h"
23#include "object-inl.h"
24#include "object_array.h"
25#include "object_array-inl.h"
26#include "object_utils.h"
27#include "sirt_ref.h"
28#include "thread.h"
29#include "utils.h"
30
31namespace art {
32namespace mirror {
33
34Array* Array::Alloc(Thread* self, Class* array_class, int32_t component_count,
35                    size_t component_size) {
36  DCHECK(array_class != NULL);
37  DCHECK_GE(component_count, 0);
38  DCHECK(array_class->IsArrayClass());
39
40  size_t header_size = sizeof(Object) + (component_size == sizeof(int64_t) ? 8 : 4);
41  size_t data_size = component_count * component_size;
42  size_t size = header_size + data_size;
43
44  // Check for overflow and throw OutOfMemoryError if this was an unreasonable request.
45  size_t component_shift = sizeof(size_t) * 8 - 1 - CLZ(component_size);
46  if (data_size >> component_shift != size_t(component_count) || size < data_size) {
47    self->ThrowNewExceptionF("Ljava/lang/OutOfMemoryError;",
48        "%s of length %d would overflow",
49        PrettyDescriptor(array_class).c_str(), component_count);
50    return NULL;
51  }
52
53  Heap* heap = Runtime::Current()->GetHeap();
54  Array* array = down_cast<Array*>(heap->AllocObject(self, array_class, size));
55  if (array != NULL) {
56    DCHECK(array->IsArrayInstance());
57    array->SetLength(component_count);
58  }
59  return array;
60}
61
62Array* Array::Alloc(Thread* self, Class* array_class, int32_t component_count) {
63  DCHECK(array_class->IsArrayClass());
64  return Alloc(self, array_class, component_count, array_class->GetComponentSize());
65}
66
67// Create a multi-dimensional array of Objects or primitive types.
68//
69// We have to generate the names for X[], X[][], X[][][], and so on.  The
70// easiest way to deal with that is to create the full name once and then
71// subtract pieces off.  Besides, we want to start with the outermost
72// piece and work our way in.
73// Recursively create an array with multiple dimensions.  Elements may be
74// Objects or primitive types.
75static Array* RecursiveCreateMultiArray(Thread* self, Class* array_class, int current_dimension,
76                                        IntArray* dimensions)
77    SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
78  int32_t array_length = dimensions->Get(current_dimension);
79  SirtRef<Array> new_array(self, Array::Alloc(self, array_class, array_length));
80  if (UNLIKELY(new_array.get() == NULL)) {
81    CHECK(self->IsExceptionPending());
82    return NULL;
83  }
84  if ((current_dimension + 1) < dimensions->GetLength()) {
85    // Create a new sub-array in every element of the array.
86    for (int32_t i = 0; i < array_length; i++) {
87      Array* sub_array = RecursiveCreateMultiArray(self, array_class->GetComponentType(),
88                                                   current_dimension + 1, dimensions);
89      if (UNLIKELY(sub_array == NULL)) {
90        CHECK(self->IsExceptionPending());
91        return NULL;
92      }
93      new_array->AsObjectArray<Array>()->Set(i, sub_array);
94    }
95  }
96  return new_array.get();
97}
98
99Array* Array::CreateMultiArray(Thread* self, Class* element_class, IntArray* dimensions) {
100  // Verify dimensions.
101  //
102  // The caller is responsible for verifying that "dimArray" is non-null
103  // and has a length > 0 and <= 255.
104  int num_dimensions = dimensions->GetLength();
105  DCHECK_GT(num_dimensions, 0);
106  DCHECK_LE(num_dimensions, 255);
107
108  for (int i = 0; i < num_dimensions; i++) {
109    int dimension = dimensions->Get(i);
110    if (UNLIKELY(dimension < 0)) {
111      self->ThrowNewExceptionF("Ljava/lang/NegativeArraySizeException;",
112                               "Dimension %d: %d", i, dimension);
113      return NULL;
114    }
115  }
116
117  // Generate the full name of the array class.
118  std::string descriptor(num_dimensions, '[');
119  descriptor += ClassHelper(element_class).GetDescriptor();
120
121  // Find/generate the array class.
122  ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
123  Class* array_class = class_linker->FindClass(descriptor.c_str(), element_class->GetClassLoader());
124  if (UNLIKELY(array_class == NULL)) {
125    CHECK(self->IsExceptionPending());
126    return NULL;
127  }
128  // create the array
129  Array* new_array = RecursiveCreateMultiArray(self, array_class, 0, dimensions);
130  if (UNLIKELY(new_array == NULL)) {
131    CHECK(self->IsExceptionPending());
132    return NULL;
133  }
134  return new_array;
135}
136
137bool Array::ThrowArrayIndexOutOfBoundsException(int32_t index) const {
138  Thread::Current()->ThrowNewExceptionF("Ljava/lang/ArrayIndexOutOfBoundsException;",
139      "length=%i; index=%i", length_, index);
140  return false;
141}
142
143bool Array::ThrowArrayStoreException(Object* object) const {
144  Thread::Current()->ThrowNewExceptionF("Ljava/lang/ArrayStoreException;",
145      "%s cannot be stored in an array of type %s",
146      PrettyTypeOf(object).c_str(), PrettyTypeOf(this).c_str());
147  return false;
148}
149
150template<typename T>
151PrimitiveArray<T>* PrimitiveArray<T>::Alloc(Thread* self, size_t length) {
152  DCHECK(array_class_ != NULL);
153  Array* raw_array = Array::Alloc(self, array_class_, length, sizeof(T));
154  return down_cast<PrimitiveArray<T>*>(raw_array);
155}
156
157template <typename T> Class* PrimitiveArray<T>::array_class_ = NULL;
158
159// Explicitly instantiate all the primitive array types.
160template class PrimitiveArray<uint8_t>;   // BooleanArray
161template class PrimitiveArray<int8_t>;    // ByteArray
162template class PrimitiveArray<uint16_t>;  // CharArray
163template class PrimitiveArray<double>;    // DoubleArray
164template class PrimitiveArray<float>;     // FloatArray
165template class PrimitiveArray<int32_t>;   // IntArray
166template class PrimitiveArray<int64_t>;   // LongArray
167template class PrimitiveArray<int16_t>;   // ShortArray
168
169}  // namespace mirror
170}  // namespace art
171