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Pointer Class

Restriction: This applies to native code only.

An intrinsic problem with passing Java strings to COBOL is that Java strings are variable length whereas COBOL strings are fixed length. For COBOL to modify a predefined fixed-length field, you need to wrap the instance in a new instance of the Pointer class. The Pointer class is in the com.microfocus.cobol.lang package.

For example, here is a COBOL program that defines a PIC X(20) data item:

showbytes.cbl:
       working-storage section.
       linkage section.
       01 lnk-string     pic x(20).
       procedure division using lnk-string.
          display "lnk-string = " lnk-string.
          move "Hello from COBOL - 1" to lnk-string.
          exit program returning 0.

The corresponding Java code would be:

showbytes.java:

import com.microfocus.cobol.RuntimeSystem;
import com.microfocus.cobol.lang.Pointer;
import com.microfocus.cobol.lang.ParameterList;

public class showbytes
{
  public static void main(String[] args) throws Exception
  {
   String myString = new String("Hello to COBOL");
   Pointer ptr2String = new Pointer(myString, 20);

   RuntimeSystem.cobcall("showbytes", 
	         new ParameterList().add(ptr2String));
		   	
   myString = ptr2String.toString();

   System.out.println(myString = ["+myString+"]");
  }  
}
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