GetByteArrayElements的官方解释：
Returns the body of the primitive array. The result is valid until
the corresponding Release<Type>ArrayElements function is called.Since the returned array may be a copy of the original array, changes made to the returned array will not necessarilybe reflected in the original array until a correspondingRelease<Type>ArrayElementsis called. IfisCopyis notNULL, then*isCopyis set toJNI_TRUEif a copy is made; if no copy is made, it is set toJNI_FALSE.在使用
GetByteArrayElements时：
byteBuffer = env->GetByteArrayElements(buffer, JNI_FALSE);/* 当第二个参数为0时，个人理解此接口只是一个指针转换。但是，如果你需要确保byteBuffer 指针的数据和buffer同步(参见红色说明)，必须调用： env->ReleaseByteArrayElements(buffer, byteBuffer, 0);*/在使用
ReleaseByteArrayElements时：
env->ReleaseByteArrayElements(buffer, byteBuffer, JNI_FALSE);/*小心最后一个参数,如果为0是会释放 m 所指向的内存的. 如果M刚好指向一个栈上的数组的话,这样可能在Release 版本中造成内存方面的随机错误.可以用JNI_COMMIT来避免.*/
解决方法摘自：http://blog.csdn.net/rainlight/article/details/818964
其实现代码也许如下
+void
+KaffeJNI_ReleaseByteArrayElements(JNIEnv* env UNUSED, jbyteArray arr, jbyte* elems, jint mode) +{ + BEGIN_EXCEPTION_HANDLING_VOID(); + + if (elems != unhand_array((HArrayOfByte*)arr)->body) { + switch (mode) { + case JNI_COMMIT: + memcpy(unhand_array((HArrayOfByte*)arr)->body, elems, obj_length((HArrayOfByte*)arr) * sizeof(jbyte)); + break; + case 0: + memcpy(unhand_array((HArrayOfByte*)arr)->body, elems, obj_length((HArrayOfByte*)arr) * sizeof(jbyte)); + KFREE(elems); + break; + case JNI_ABORT: + KFREE(elems); + break; + } + } + END_EXCEPTION_HANDLING(); +}JNI_COMMIT forces the native array to be copied back to the original array in the Java virtual machine.JNI_ABORTfrees the memory allocated for the native array without copying back the new contents