JNI Template

#include <jni.h>
#include <string>
#include <assert.h>

JavaVM *globleVM = NULL;
//extern "C"
//jstring
//Java_com_feicheninfo_testjni_MainActivity_stringFromJNI(
//        JNIEnv *env,
//        jobject /* this */) {
//    std::string hello = "Hello from C++";
//    return env->NewStringUTF(hello.c_str());
//}

//JNI
__attribute__((section (".mytext")))jstring check8(JNIEnv *env, jobject thiz, jstring name) {

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

    if (strcmp(str, "feichen") == 0) {
        return name;
    }
    else {
        return env->NewStringUTF("cann't find this account");
    }
}

//自定义的JNI_OnLoad，用于混淆native函数名
#define JNIREG_CLASS "com/feicheninfo/testjni/MainActivity"//指定要注册的类

/**
* Table of methods associated with a single class.
*/

static JNINativeMethod gMethods[] = {//绑定，注意，V,Z签名的返回值不能有分号“;”
        {"check7", "(Ljava/lang/String;)Ljava/lang/String;", (void *) check8},
};

/*
* Register several native methods for one class.
*/
static int registerNativeMethods(JNIEnv *env, const char *className,
                                 JNINativeMethod *gMethods, int numMethods) {
    jclass clazz;
    clazz = env->FindClass(className);
    if (clazz == NULL) {
        return JNI_FALSE;
    }
    if (env->RegisterNatives(clazz, gMethods, numMethods) < 0) {
        return JNI_FALSE;
    }

    return JNI_TRUE;
}

static int registerNatives(JNIEnv *env) {
    if (!registerNativeMethods(env, JNIREG_CLASS, gMethods, sizeof(gMethods) / sizeof(gMethods[0])))
        return JNI_FALSE;

    return JNI_TRUE;
}

jint JNI_OnLoad(JavaVM *vm, void *reserved) {
    JNIEnv *env = NULL;
    jint result = -1;

    if (vm->GetEnv((void **) &env, JNI_VERSION_1_4) != JNI_OK) {
        return -1;
    }
    assert(env == NULL);

    if (!registerNatives(env)) {//注册
        return -1;
    }
    /* success -- return valid version number */
    globleVM = vm;
    result = JNI_VERSION_1_4;

    return result;
}

void JNI_OnUnload(JavaVM *vm, void *reserved) {

    globleVM = NULL;
}