Android将“.c”后缀名改成“.cpp”时java调用native失败及“error: base operand of '-＞' has non-poin

#include "c_example_com_jni_jnidemo.h"
#include <string.h>

/*
* Class:     io_github_yanbober_ndkapplication_NdkJniUtils
* Method:    getCLanguageString
* Signature: ()Ljava/lang/String;
*/

JNIEXPORT jstring JNICALL Java_c_example_com_jni_jnidemo_SayHello
(JNIEnv *env, jclass obj){
//     return (*env)->NewStringUTF(env,"This just a test for Android Studio NDK JNI developer!");
return env->NewStringUTF("HelloWorld from JNI !");
}