JNI: calling java

From: Thomas Smith (thomas.smith_at_cox.net)
Date: 10/08/04 

Date: Fri, 8 Oct 2004 16:31:27 -0400

I am having a bear of a time making a return call from C++ back to a java
Object.
I keep getting a NoSuchMethod Exception. Unfortunately, I see different
possible signatures in several different articles.
Can anyone out there give me a definitive answer on this?

here is the java Code:

public class CPlusPlusTest {

 static{
  System.loadLibrary("JNITest");
   }
  public void callMe(){
  System.out.println("java was called");
 }
 public native void doHello();

 public static void main(String[] args) {

  new CPlusPlusTest().doHello();

 }
}

and here is the C++ code:

VOID Java_com_ts_jni_play_CPlusPlusTest_doHello
  (JNIEnv * env, jobject jObj){
    printf("do hello called natively");
    jclass cls=env->GetObjectClass(jObj);
    if(cls==0) printf("class not found");
  } 

-- 
Thomas W. Smith
Senior Engineer

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