JNI。如何从 jobject 获取 jstring 并将其转换为 char*

Question

这是我目前所拥有的： 我传递一个具有 2 个字段的对象：字符串和整数，作为参数 我想发送信息以在 C 部分处理它，这在这一点上并不重要...... 我在 jstring 声明中受到抱怨

JNIEXPORT jint JNICALL Java_Tier3_NativeMethods_totalPalletsIn(
            JNIEnv *env, jclass cls, jobject stat) {

jclass staticsitcs = (*env)->GetObjectClass(env, stat);

// Here I try to get it using the ID
jfieldID idDate = (*env)->GetFieldID(env, staticsitcs, "date", "S");

jstring dateString = (jstring)(*env)->GetStringRegion(env, stat, idDate);

// Here converting whatever I get in jstring to char*
char* date = (*env)->GetStringUTFChars(env,dateString,0);

// Getting the 2nd field from the object
jfieldID idNumber = (*env)->GetFieldID(env, staticsitcs, "amount", "I");

jint amount = (*env)->GetDoubleField(env, stat, idNumber);

// Calling C method
jint totalPallets = checkTotalPalletsIn(date, amount);

(*env)->ReleaseStringUTFChars(env, dateString, date);

return totalPallets;
}

我错过了什么？

Answer 1

jstring dateString = (jstring)(*env)->GetObjectField(env, stat, idDate);

... 之后一切正常。