1 /* 2 * Copyright (C) 2010 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 #ifndef SCOPED_PRIMITIVE_ARRAY_H_included 18 #define SCOPED_PRIMITIVE_ARRAY_H_included 19 20 #include "JNIHelp.h" 21 22 // ScopedBooleanArrayRO, ScopedByteArrayRO, ScopedCharArrayRO, ScopedDoubleArrayRO, 23 // ScopedFloatArrayRO, ScopedIntArrayRO, ScopedLongArrayRO, and ScopedShortArrayRO provide 24 // convenient read-only access to Java arrays from JNI code. This is cheaper than read-write 25 // access and should be used by default. 26 #define INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(PRIMITIVE_TYPE, NAME) \ 27 class Scoped ## NAME ## ArrayRO { \ 28 public: \ 29 Scoped ## NAME ## ArrayRO(JNIEnv* env, PRIMITIVE_TYPE ## Array javaArray) \ 30 : mEnv(env), mJavaArray(javaArray), mRawArray(NULL) { \ 31 if (mJavaArray == NULL) { \ 32 jniThrowNullPointerException(mEnv, NULL); \ 33 } else { \ 34 mRawArray = mEnv->Get ## NAME ## ArrayElements(mJavaArray, NULL); \ 35 } \ 36 } \ 37 ~Scoped ## NAME ## ArrayRO() { \ 38 if (mRawArray) { \ 39 mEnv->Release ## NAME ## ArrayElements(mJavaArray, mRawArray, JNI_ABORT); \ 40 } \ 41 } \ 42 const PRIMITIVE_TYPE* get() const { return mRawArray; } \ 43 const PRIMITIVE_TYPE& operator[](size_t n) const { return mRawArray[n]; } \ 44 size_t size() const { return mEnv->GetArrayLength(mJavaArray); } \ 45 private: \ 46 JNIEnv* mEnv; \ 47 PRIMITIVE_TYPE ## Array mJavaArray; \ 48 PRIMITIVE_TYPE* mRawArray; \ 49 Scoped ## NAME ## ArrayRO(const Scoped ## NAME ## ArrayRO&); \ 50 void operator=(const Scoped ## NAME ## ArrayRO&); \ 51 } 52 53 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jboolean, Boolean); 54 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jbyte, Byte); 55 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jchar, Char); 56 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jdouble, Double); 57 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jfloat, Float); 58 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jint, Int); 59 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jlong, Long); 60 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO(jshort, Short); 61 62 #undef INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RO 63 64 // ScopedBooleanArrayRW, ScopedByteArrayRW, ScopedCharArrayRW, ScopedDoubleArrayRW, 65 // ScopedFloatArrayRW, ScopedIntArrayRW, ScopedLongArrayRW, and ScopedShortArrayRW provide 66 // convenient read-write access to Java arrays from JNI code. These are more expensive, 67 // since they entail a copy back onto the Java heap, and should only be used when necessary. 68 #define INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(PRIMITIVE_TYPE, NAME) \ 69 class Scoped ## NAME ## ArrayRW { \ 70 public: \ 71 Scoped ## NAME ## ArrayRW(JNIEnv* env, PRIMITIVE_TYPE ## Array javaArray) \ 72 : mEnv(env), mJavaArray(javaArray), mRawArray(NULL) { \ 73 if (mJavaArray == NULL) { \ 74 jniThrowNullPointerException(mEnv, NULL); \ 75 } else { \ 76 mRawArray = mEnv->Get ## NAME ## ArrayElements(mJavaArray, NULL); \ 77 } \ 78 } \ 79 ~Scoped ## NAME ## ArrayRW() { \ 80 if (mRawArray) { \ 81 mEnv->Release ## NAME ## ArrayElements(mJavaArray, mRawArray, 0); \ 82 } \ 83 } \ 84 const PRIMITIVE_TYPE* get() const { return mRawArray; } \ 85 const PRIMITIVE_TYPE& operator[](size_t n) const { return mRawArray[n]; } \ 86 PRIMITIVE_TYPE* get() { return mRawArray; } \ 87 PRIMITIVE_TYPE& operator[](size_t n) { return mRawArray[n]; } \ 88 size_t size() const { return mEnv->GetArrayLength(mJavaArray); } \ 89 private: \ 90 JNIEnv* mEnv; \ 91 PRIMITIVE_TYPE ## Array mJavaArray; \ 92 PRIMITIVE_TYPE* mRawArray; \ 93 Scoped ## NAME ## ArrayRW(const Scoped ## NAME ## ArrayRW&); \ 94 void operator=(const Scoped ## NAME ## ArrayRW&); \ 95 } 96 97 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jboolean, Boolean); 98 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jbyte, Byte); 99 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jchar, Char); 100 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jdouble, Double); 101 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jfloat, Float); 102 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jint, Int); 103 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jlong, Long); 104 INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW(jshort, Short); 105 106 #undef INSTANTIATE_SCOPED_PRIMITIVE_ARRAY_RW 107 108 #endif // SCOPED_PRIMITIVE_ARRAY_H_included 109