JNIjw06

1、VC6(CPP)的DLL代码：

#include<stdio.h>
#include "jniZ_JNIjw06.h"

// 全局变量
jfieldID g_propInt_id = 0;
jfieldID g_propStr_id = 0;

JNIEXPORT void JNICALL Java_jniZ_JNIjw06_InitNativeIDs (JNIEnv * env, jclass clazz)
{
    printf("Java_jniZ_JNIjw06_InitNativeIDs - 1
");

    g_propInt_id = env->GetFieldID(clazz, "propInt", "I");
    g_propStr_id = env->GetFieldID(clazz, "propStr", "Ljava/lang/String;");

    printf("Java_jniZ_JNIjw06_InitNativeIDs - 2
");
}

JNIEXPORT void JNICALL Java_jniZ_JNIjw06_OtherNative (JNIEnv * env, jobject obj)
{
    printf("Java_jniZ_JNIjw06_OtherNative - 1
");

    // get field with g_propInt_id / g_propStr_id ...
    
    printf("Java_jniZ_JNIjw06_OtherNative - 2
");
}

2、Java代码：

package jniZ;

public class JNIjw06
{
    static
    {
        InitNativeIDs();
    }
    
    static native void InitNativeIDs();
    
    int propInt = 0;
    String propStr = "";
    
    public native void OtherNative();
    
    public static void main(String[] args)
    {
        Object ll;
    }
}

3、Java控制台输出：

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