2.3.md

Java基本数据类型在JNI中对应的类型

public class JNIBasicTypes {
    static {
        System.loadLibrary("native-lib");
    }

    public native int callNativeInt(int num);

    public native byte callNativeByte(byte b);

    public native char callNativeChar(char ch);

    public native short callNativeShort(short sh);

    public native long callNativeLong(long l);

    public native float callNativeFloat(float f);

    public native double callNativeDouble(double d);

    public native boolean callNativeBoolean(boolean value);
}

extern "C"
JNIEXPORT jint JNICALL
Java_com_jdqm_ndktutorials_jni_JNIBasicTypes_callNativeInt(JNIEnv *env, jobject thiz, jint num) {
    LOGD("java int value is %d",num);
    int c_num=num *2;
    return c_num;
}

extern "C"
JNIEXPORT jbyte JNICALL
Java_com_jdqm_ndktutorials_jni_JNIBasicTypes_callNativeByte(JNIEnv *env, jobject thiz,
                                                                jbyte b) {
    LOGD("java byte value is %d", b);
    jbyte c_byte = b + (jbyte) 10;
    return c_byte;
}


extern "C"
JNIEXPORT jchar JNICALL
Java_com_jdqm_ndktutorials_jni_JNIBasicTypes_callNativeChar(JNIEnv *env, jobject thiz,
                                                                jchar ch) {
    LOGD("java char value is %c", ch);
    jchar c_char = ch + (jchar) 3;
    return c_char;
}

extern "C"
JNIEXPORT jshort JNICALL
Java_com_jdqm_ndktutorials_jni_JNIBasicTypes_callNativeShort(JNIEnv *env, jobject thiz,
                                                                 jshort sh) {
    LOGD("java char value is %d", sh);
    jshort c_short = sh + (jshort) 10;
    return c_short;
}

extern "C"
JNIEXPORT jlong JNICALL
Java_com_jdqm_ndktutorials_jni_JNIBasicTypes_callNativeLong(JNIEnv *env, jobject thiz,
                                                                jlong l) {
    LOGD("java long value is %ld", l);
    jlong c_long = l + 100;
    return c_long;
}


extern "C"
JNIEXPORT jfloat JNICALL
Java_com_jdqm_ndktutorials_jni_JNIBasicTypes_callNativeFloat(JNIEnv *env, jobject thiz,
                                                                 jfloat f) {
    LOGD("java float value is %f", f);
    jfloat c_float = f + (jfloat) 10.0;
    return c_float;
}


extern "C"
JNIEXPORT jdouble JNICALL
Java_com_jdqm_ndktutorials_jni_JNIBasicTypes_callNativeDouble(JNIEnv *env, jobject thiz,
                                                                  jdouble d) {
    LOGD("java double value is %f", d);
    jdouble c_double = d + 20.0;
    return c_double;
}

extern "C"
JNIEXPORT jboolean JNICALL
Java_com_jdqm_ndktutorials_jni_JNIBasicTypes_callNativeBoolean(JNIEnv *env, jobject thiz,
                                                                   jboolean value) {
    LOGD("java boolean value is %d", value);
    jboolean c_bool = (jboolean) !value;
    return c_bool;
}