jni 与java 之间传递bytearray

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要实现在java 端传递bytearray 到jni 端,同时在jni 端要反馈回bytearray

在java 端的声明如下:

public native byte[] Bluetooth_NativeProcessData_Send(byte[] data,int len);
public native byte[] Bluetooth_NativeProcessData_Receive(byte[] data,int len);

如下是jni 端的声明

static JNINativeMethod gMethods[] = {
{"Bluetooth_NativeProcessData_Send","([BI)[B",(void*)Native_ProcessData_Send},
{"Bluetooth_NativeProcessData_Receive","([BI)[B",(void*)Native_ProcessData_Receive},
};

在jni 端的实现:

jbyte gs_raw_data[256];
jbyte gr_raw_data[256];

JNIEXPORT jbyteArray JNICALL Native_ProcessData_Send(JNIEnv *env, jobject clazz, jbyteArray data,jint len)
{

jclass cls;
int i;
cls = env->FindClass(JNIREG_CLASS);
jbyte* bytedata =env->GetByteArrayElements(data, 0);

memset(&gs_raw_data,0,255);
memcpy(&gs_raw_data,bytedata,len);

// parse the data
//below is the return 's bytearray lens

jbyteArray jarrRV =env->NewByteArray(len+1);

env->SetByteArrayRegion(jarrRV, 0,len,gs_raw_data);

return jarrRV;
}

JNIEXPORT jbyteArray JNICALL Native_ProcessData_Receive(JNIEnv *env, jobject clazz, jbyteArray data,jint len)
{
jclass cls;
   int i;
   cls = env->FindClass(JNIREG_CLASS);
   jbyte* bytedata =env->GetByteArrayElements(data, 0);

       memset(&gr_raw_data,0,255);
       memcpy(&gr_raw_data,bytedata,len);
   // parse the data and process your data
      //try to process the data
              for(i=0;i<len;i++)
              {
                gr_raw_data[i]=bytedata[i]+1;
              }
       //after proces the data, you can return the processed data lens which may be different the raw len
     // note below is the return 's bytearray lens
     jbyteArray jarrRV =env->NewByteArray(len+1);

env->SetByteArrayRegion(jarrRV, 0,len,gs_raw_data);

return jarrRV;
}

//blow is the java to call jni and pass the byte array to jni and return from jni

public void test(t) {
        // Create temporary object
    int ilength,i;
    byte[] retdata;
    byte[] out1 = new byte[1024];

        {
        out1[0] =(byte) 0X31;
        out1[1] =(byte) 0X32;
        out1[2] =0x33;
        out1[3] =0x34;
        out1[4] = 0x35;
        }

        retdata=Bluetooth_NativeProcessData_Send(out1,5);

        {
        Log.d(TAG,"THE rawdata IS---"+bytesToHex(out1,5));
        Log.d(TAG,"THE RETDATA IS---"+bytesToHex(retdata,5));

        }

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