JVM COBOL Passing Java Instances to Native Object COBOL

In earlier Micro Focus products, COBOL and Java interoperability was achieved using a class and method Wizard to create Java classes that extend the class com.microfocus.cobol.RuntimeObject and its companion COBOL class.

You can now use these generated classes with JVM COBOL applications, enabling you to pass a Java instance to native object COBOL by creating an instance of the com.microfocus.cobol.RuntimeObject. The native COBOL receives these instances as native object references.

In the following example, the Java class addressbook extends com.microfocus.cobol.RuntimeObject and is used to create an instance:

 working-storage section.
 01 ab    type addressbook.
 procedure division.
     set ab to type addressbook::new()
     call "useab_oon" using by value ab

The receiving native COBOL program:

$set ooctrl(+p) ooctrl(-f) dialect(iso2002) mf warning(1)
 identification division.
 program-id. useab_con as "useab_oon".
 repository.
    class cls-sb as "$java$java.lang.StringBuffer".
 working-storage section.
 01 nameBuffer       object reference.
 01 nameBufferLength binary-long.
 01 nameBufferX       pic x(80).
 linkage section.
 01 ab                   object reference.
 procedure division using by value ab.
     invoke cls-sb "new" using
         by value 80 size 4
         returning nameBuffer
     invoke ab "getName" using nameBuffer
     invoke nameBuffer "length" returning nameBufferLength
     invoke nameBuffer "toString" returning nameBufferX
     display "Customer name : " nameBufferX(1:nameBufferLength)
     invoke nameBuffer "finalize" returning nameBuffer
     goback.

The native COBOL class:

$set ooctrl(+p) ooctrl(-f) dialect(iso2002) mf warning(1)
 identification division.
 class-id. addressBook as "addressbook" 
           inherits from javabase.
    
 repository.
     class javabase as "javabase"
 factory.
 working-storage section.
 end factory.
 object. 
 working-storage section.

 method-id.  getName .
 linkage Section.
 01 customerName           pic x(80).
 procedure division using by reference customerName.
     move "Mr Smith" to customerName
 exit method.
 end method getName.
 end object.

 end class addressBook.

And finally, addressbook.java, which is automatically generated:

import com.microfocus.cobol.*;
// OCWIZARD start imports
// OCWIZARD end imports

public class addressbook extends com.microfocus.cobol.RuntimeObject
{
 /* static methods - the COBOL runtime will register these */
 public native static boolean cobinvokestatic_boolean (String methodName, Object[] params)
  throws CobolException, Exception;
 public native static byte cobinvokestatic_byte (String methodName, Object[] params)
  throws CobolException, Exception;
 public native static char cobinvokestatic_char (String methodName, Object[] params)
  throws CobolException, Exception;
 public native static short cobinvokestatic_short (String methodName, Object[] params)
  throws CobolException, Exception;
 public native static int cobinvokestatic_int (String methodName, Object[] params)
  throws CobolException, Exception;
 public native static long cobinvokestatic_long (String methodName, Object[] params)
  throws CobolException, Exception;
 public native static float cobinvokestatic_float (String methodName, Object[] params)
  throws CobolException, Exception;
 public native static double cobinvokestatic_double (String methodName, Object[] params)
  throws CobolException, Exception;
 public native static void cobinvokestatic_void (String methodName, Object[] params)
  throws CobolException, Exception; 
 public native static Object cobinvokestatic_Object (String methodName, Object[] params)
  throws CobolException, Exception;

 static private String javaClassName = "addressbook";
 static
 {
  /* Load the class */
  /* cobloadclass (libraryname, cobolname, fulljavaname); */
  cobloadclass ("addressbook", "addressbook", javaClassName);
 }

 // OCWIZARD - start java methods

 public  void getName (StringBuffer customerName) throws Exception, CobolException
 {
  // Parameters are passed to COBOL in an array
  Object[] params = {customerName};
  cobinvoke_void ("getName", params);
 }
 // OCWIZARD - end java methods
}