这是示例 jni 方法，我在其中创建了一个字符串并将其返回给调用 java 方法：
jstring
Java_com_example_hellojni_HelloJni_stringFromJNI( JNIEnv* env,
jobject thiz )
{
char test[100];
sprintf(test, "Test%03d.txt", rand()/100);
jstring returnVal = (*env)->NewStringUTF(env, test);
(*env)->DeleteLocalRef(env,returnVal);
return returnVal;
}
由于我删除了本地引用，因此我期望 jstring 在调用 java 方法中无效。但参考仍然有效。我明确调用 System.gc() 来查看 GC 是否清除它，但它没有发生。
据此：http ://android-developers.blogspot.com/2011/11/jni-local-reference-changes-in-ics.html
"Bug: Calling DeleteLocalRef() and continuing to use the deleted reference
It shouldn’t need to be said that it’s illegal to continue to use a reference after calling DeleteLocalRef() on it, but because it used to work, so you may have made this mistake and not realized. The usual pattern seems to be where native code has a long-running loop, and developers try to clean up every single local reference as they go to avoid hitting the local reference limit, but they accidentally also delete the reference they want to use as a return value!
The fix is trivial: don’t call DeleteLocalRef() on a reference you’re going to use (where “use” includes “return”)."
我对这种不一致感到有点困惑。