Use a Java class (PB9)

Consider the following simple class :

[Simple.java]
public class Simple {
    public Simple() {  }
    public static String sayHello(){
        return "Hello world";
    }
    public String sayNonStaticHello(){
        return "Hello world";
    }    
    public static void main(String[] args) {
        System.out.println(Simple.sayHello());
    }
}

[SimpleHome.java]
public interface SimpleHome { }

1. Start Powerbuilder.
2. Create a new application, call it "pbjsimple", put everything in the same directory(.class and .pbl).
3. Start the EJB Proxies Wizard, Type "Simple" as the component and the classpath is the folder containing the "Simple.class" file.
4. Run the project, Powerbuilder will generate proxies for your classes and also for most standard Java classes!
5. Next, open a window from the application and drop a Button and insert the following Powerscript in the "click event".

   JavaVM lJavaVM
   EJBConnection lEJBConn
   Simple lnv_simple
   long    ll_return
   
   lJavaVM = CREATE JavaVM
   
   // need to specify the classpath form the Simple class
   ll_return = &
      lJavaVM.CreateJavaVM("C:\Applications\rega\dev\Work\pb9\Target3", FALSE)
   CHOOSE CASE ll_return
       CASE 1
       CASE 0
       CASE -1
          MessageBox ( "", "jvm.dll was not found in the classpath.")
       CASE -2
          MessageBox ( "", "pbejbclient90.jar file was not found." )
       CASE ELSE
          MessageBox ( "", "Unknown result (" + String (ll_return ) + ")"  )
   END CHOOSE
   
   IF ll_return < 0 THEN
      DESTROY lJavaVM
   END IF
   
   lEJBConn = CREATE EJBConnection
   ll_return = lEJBConn.CreateJavaInstance( lnv_simple, "Simple")
   IF ll_return <> 0 THEN
      MessageBox("", "CreateJavaInstance returned " +string(ll_return))
      destroy lEJBConn
   ELSE
      TRY
        MessageBox("From Java!" , lnv_simple.sayNonStaticHello())
      CATCH (CreateException ce)
        MessageBox( "Create Exception", ce.getMessage() )
      CATCH (Throwable t)
        MessageBox(" Other Exception", t.getMessage())
      END TRY
   END IF
   

   Note : AFAIK Java static methods are not visible from Powerbuilder.

You can download this example here

Written and compiled by Réal Gagnon ©1998-2005
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