JNI和Qt通信(Part2)

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JNIEXPORT void JNICALL Java_JNISample_sampleFunction(JNIEnv* env, jobject obj, jstring name)

{

const char* pname = env->GetStringUTFChars(name, NULL);

env->ReleaseStringUTFChars(name, pname);

}

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JNIEXPORT jint JNICALL Java_IntArray_sumArray

(JNIEnv *env, jobject obj, jintArray arr) {

jint buf[10];

jint i, sum = 0;

// This line is necessary, since Java arrays are not guaranteed

// to have a continuous memory layout like C arrays.

env->GetIntArrayRegion(arr, 0, 10, buf);

for (i = 0; i < 10; i++) {

sum += buf[i];

}

return sum;

}

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// In "win\jni_mh.h" - machine header which is machine dependent

typedef long jint;

typedef __int64 jlong;

typedef signed char jbyte;

// In "jni.h"

typedef unsigned char jboolean;

typedef unsigned short jchar;

typedef short jshort;

typedef float jfloat;

typedef double jdouble;

typedef jint jsize;

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class JNISample

{

public native void launchSample();

static

{

System.loadLibrary("Sample");

}

public static int add(int a,int b) {

return a+b;

}

public boolean judge(boolean bool) {

return !bool;

}

}

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JNIEnv *env = GetJNIEnv(); //Get env from JNI

jclass cls;

cls = env->FindClass("JNISample");

if(cls !=0)

{

printf("find java class success\n");

// constructor

mid = env->GetMethodID(cls,"","()V");

if(mid !=0)

{

jobj=env->NewObject(cls,mid);

}

// static function

mid = env->GetStaticMethodID( cls, "add", "(II)I");

if(mid !=0)

{

square = env->CallStaticIntMethod( cls, mid, 5,5);

}

// function returns boolean

mid = env->GetMethodID( cls, "judge","(Z)Z");

if(mid !=0){

jnot = env->CallBooleanMethod(jobj, mid, 1);

}

}

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javap -s -p -classpath R:\test.Demo

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#ifdef JNI_VERSION_1_4

printf("Version is 1.4 \n");

#endif

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jint GetVersion(JNIEnv *env);