FUJITSU J Adapter Class Generator - Manual (Page 11)

Chapter 1. Outline of J Adapter Class Generator 11
The Java class interface must be converted into the COBOL interface for a COBOL
program to use Java classes. The J adapter class generator generates an adapter
class that converts the Java interface into the COBOL interface.
What the J Adapter Class Generator Can Do
Using adapter classes generated by the J adapter class generator enables the
following types of operation for Java.
To COBOL programs, Java objects seem to be COBOL objects. Therefore, Java
objects can be handled the same way as ordinary COBOL objects.
•
•
•
•
•
•
Accessing a class variable
Access to a public class variable (static field) declared in a Java class is enabled.
COBOL handles it as a factory property.
Invoking a class method
A public class method (static method) declared in a Java class can be invoked.
COBOL handles it as a factory method.
Generating an instance object (invoking a constructor)
Invoking a constructor can create a Java instance object. COBOL handles it as a
factory method that returns an object.
Accessing an instance variable
Access to a public instance variable (non-static field) of a Java instance object is
enabled. COBOL handles it as an object property.
Invoking an instance method
A public instance method (non-static method) of a Java instance object can be
invoked. COBOL handles it as an object method.
Receiving an exception
An exception caused when a class method, constructor, or instance method is
invoked can be trapped to perform error processing. COBOL uses the USE
statement to receive an exception object.
What the J Adapter Class Generator Cannot Do
The J adapter class generator cannot perform the following types of operation:
•
•
Inheriting a Java class
A COBOL class inheriting a Java class cannot be defined. Even if a COBOL class
inherits an adapter class, the Java class function cannot be overwritten.
Passing a COBOL object as a parameter
No COBOL object can be passed as a parameter for invoking a method, nor can
a COBOL object be set for a Java field. Only an adapter object produced by
wrapping a Java object can be passed to Java.