jni jnienv NewByteArray example c c++ java

New<PrimitiveType>Array Routines - NewByteArray

ArrayType New<PrimitiveType>Array(JNIEnv *env, jsize length);

A family of operations used to construct a new primitive array object. Table 4-8 describes the specific primitive array constructors. You should replace New<PrimitiveType>Array with one of the actual primitive array constructor routine names from the following table, and replace ArrayType with the corresponding array type for that routine.

Table 4-8a New<PrimitiveType>Array Family of Array Constructors

New<PrimitiveType>Array Routines	Array Type
NewBooleanArray()	jbooleanArray
NewByteArray()	jbyteArray
NewCharArray()	jcharArray
NewShortArray()	jshortArray
NewIntArray()	jintArray
NewLongArray()	jlongArray
NewFloatArray()	jfloatArray
NewDoubleArray()	jdoubleArray

LINKAGE:

Indices in the JNIEnv interface function table.

Table 4-8b New<PrimitiveType>Array Family of Array Constructors

New<PrimitiveType>Array Routines	Index
NewBooleanArray()	175
NewByteArray()	176
NewCharArray()	177
NewShortArray()	178
NewIntArray()	179
NewLongArray()	180
NewFloatArray()	181
NewDoubleArray()	182

PARAMETERS of NewByteArray

env: the JNI interface pointer.

length: the array length.

RETURNS of NewByteArray

Returns a Java array, or NULL if the array cannot be constructed.

Example of NewByteArray

void add(char* key, char* value, int length)
{
 jstring j_key = (*env)->NewStringUTF(env, key);
 jbyteArray j_value = (*env)->NewByteArray(env, length);

 (*env)->SetByteArrayRegion(env, j_value, 0, length, (jbyte *)value);
 ret = (*env)->CallStaticBooleanMethod(env, j_store, method_id, j_key, j_value);

 if(j_value != null)
 {
  (*env)->ReleaseByteArrayElements(env, j_value, (jbyte *)value, 0);
 }
 if(j_key != null)
 {
  (*env)->ReleaseStringUTFChars(env, j_key, key);
 }
}