如何在Java中管理多线程？

Question

I have a Java function that is multi-threaded by OSB (oracle service BUs).      This Java function calling three different native function through JNI. How to      call     these three function in such a way that :

1. first function (setting up the system) will call only for 1st thread.
2. 2nd function will call by all thread.

3. 3rd function(cleaning up the system) will call only by the last thread. Native functions

   setup();

   calculation();

   Cleanup();

   JNI functions

   JNIEXPORT jvoid JNICALL Java_taxcalc_setup

   JNIEXPORT jstring JNICALL Java_taxcalc_calculation

   JNIEXPORT jvoid JNICALL Java_taxcalc_cleanup

   Java Code

   public class taxcalc{

    private static native void setup(); private static native String calculation(String input[],double y,int); private static native void cleanup(); static{ System.loadLibrary("CJavaInterface_64"); taxcalc.setup(); taxcalc.cleanup(); } 

   public static String taxoutput(String[] args){

   String array="";

   for(int j=0;j<=5;j++)

   {

    input[j]=args[j]; 

   }

   double y;

   int BilledLines;

   y=Double.parseDouble(args[6]);

   BilledLines=Integer.parseInt(args[7]);

   array=taxcalc.calculation(input,y,BilledLines,);

   return array;

   }

   public static void main(String[] args){

     System.out.println(taxoutput(args)); } 

   }

   taxouput function is multithreaded from osb.now,i want to call setup() and
   cleanup() in way that it,setup() should called only for first thread and
   cleanup() should call only for last thread.

Answer 1

From the code it seems you need to initialize and clean up using native functions. This can be done using java multithreading but I would first look out for call back events in OSB from which you can invoke setup() and cleanup() methods . This way it would be more cleaner.