Applications that use the native Object-Oriented (OO) COBOL syntax will probably require significant work to migrate them
to
JVM COBOL. We recommend that you contact
Micro Focus
Customer Care for extra help with this.
Some of the significant differences between native OO COBOL and
JVM COBOL are:
- JVM COBOL code is typed, unlike native OO COBOL. The Compiler enforces type checking on object references in
JVM COBOL. This is different to native OO COBOL where all object references are simply of type "object" and can hold a reference to
instances of any class of object.
- Object references must be defined at level-01 in
JVM COBOL, because the compiled code and the run-time system now conform to the rules for type-safe code. This conforms with the ISO2002
COBOL standard.
- The Micro Focus OO class libraries are not supported for
JVM COBOL.
- The CLASS-OBJECT syntax is not available in
JVM COBOL.
- Multiple inheritance is not supported in native OO COBOL, although it is part of the ISO 2002 standard.
JVM COBOL supports single inheritance of classes, but you can inherit (implement) multiple interfaces.
- Interface files (.if) and the vocabularies syntax do not have an equivalent in
JVM COBOL.