how to convert jobject to jstring

c++, cocos2d-x, java, java-native-interface

Solution

Here you go ...

const char* GetIDJni() {

    JniMethodInfo t;

        if (JniHelper::getStaticMethodInfo(t, CLASS_NAME, "GetIDJni", "()Ljava/lang/String;")) {
            jstring str = (jstring)t.env->CallStaticObjectMethod(t.classID, t.methodID);
            t.env->DeleteLocalRef(t.classID);
            CCString *ret = new CCString(JniHelper::jstring2string(str).c_str());
            ret->autorelease();
            t.env->DeleteLocalRef(str);

            return ret->m_sString.c_str();
        }

        return 0;
    }

And if you want to get it return as std::String then

std::string GetIDJni() {
  std::string ret;
JniMethodInfo t;

    if (JniHelper::getStaticMethodInfo(t, CLASS_NAME, "GetIDJni", "()Ljava/lang/String;")) {
        jstring str = (jstring)t.env->CallStaticObjectMethod(t.classID, t.methodID);
        t.env->DeleteLocalRef(t.classID);
        ret=JniHelper::jstring2string(str);
        t.env->DeleteLocalRef(str);

        return ret;
    }

    return 0;
}

Problem

I am trying to get a string in return to a function call from cpp to java. This is my JNI call ``` string GetIDJni() { cocos2d::JniMethodInfo methodInfo; if (! JniHelper::getStaticMethodInfo(methodInfo, CLASS_NAME, "GetID", "()Ljava/lang/String")) { return ""; } jobject retObj = methodInfo.env->CallStaticObjectMethod(methodInfo.classID, methodInfo.methodID); jstring retStr = (jstring)retObj; methodInfo.env->DeleteLocalRef(methodInfo.classID); return (JniHelper::jstring2string(retStr)); } ``` On compiling i get the error error: invalid conversion from '_jobject*' to '_jstring*' Can anyone please tell me how to solve this problem.

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