Java For RPG Programmers

Introduction

Object-oriented (OO) technology has become increasingly important for managing the complexity inherent in systems analysis, design, and implementation.

Java is a object-oriented language, considered by many to be a simplified and improved C++. It's easier to learn than C++, and it is more portable than programs written in any other language.

Java has found its place in both back-end servers (in the form of servlets and Enterprise JavaBeans) and front-end browsers (in the form of applets). Java is a full-featured, secure, robust, elegant, object-oriented language that is quickly becoming the choice language for today’s developers.

This five-day Java course includes comprehensive coverage of the Java language (with an introduction to Object-Oriented programming).

Through a combination of lecture and simple exercises, attendees learn the benefits of encapsulation, inheritance, and polymorphism, and learn how these object-oriented concepts are implemented in Java.

Who should attend

RPG developers who wish to start taking advantage of Java, and who wish to be capable of writing advanced Java applications or applets.

Pre-requisites

Attendees must attend the OBJECT ORIENTED CONCEPTS or the OBJECT ORIENTED ANALYSIS & DESIGN course prior to this course.

Attendees need to be experienced RPG programmers. Delegates with a working knowledge of RPGIV (with or without ILE) normally cope much better than those with just RPG/400.

Attendees without an RPG background will find one of our other Java courses listed in our Java brochure more appropriate.

What you will learn

On completion of this course, you will be able to:

• Implement programs using encapsulation, inheritance, and polymorphism in Java.
• Describe ways in which object-oriented technology helps reduce software-development costs.
• Understand and explain the benefits of encapsulation, inheritance, and polymorphism.
• Read, understand, and discuss object-oriented literature.
• Write, compile, debug, and execute Java applications and applets.
• Use Java’s object-oriented features, including encapsulation, inheritance, and polymorphism.
• Use packages, interfaces, abstract classes, constructors and finalize methods, and more.
• Use classes from the AWT and Swing packages, including layout managers and visual components to create interactive GUIs.
• Handle events with the Java event delegation model.
• Use threads to increase an application’s performance and functionality.
• Use exception handling to create industrial strength applications.
• Draw using colours and fonts.
• Use numerous other classes, including Vectors/Enumeration, Strings, StringBuffers, and more.

Practical Work

Approximately 50% of this course is devoted to practical assignments, ranging from the construction of simple Java objects to building an application using Java.

Course content

Introduction to Java

• Application models.
• House of Java.
• Java the language.
• The Internet, HTML and Java applets.
• Java applications.

The Java Onion

• RPG versus Java.
• Using Java classes.
• RPG procedures and Java methods.
• RPG service programs and Java packages.
• RPG static variables, Java static variables, Java static methods.
• RPG scoping and Java scoping.
• Class constructors in Java.
• RPG mainline code and Java main method.

Java Language and Syntax

• Java basics, comments in Java programs.
• Naming syntax for variables and fields.
• Java statements.
• Expressions and operators.
• Other mathematical functions.

Structured Operations and Statements

• Control structures.
• Alternate paths, decision structures.
• If, then, else, switch, conditional operators.
• Looping for a while, looping until done.
• Transfer structures.

Data Types and Variables

• Defining fields in RPG and variables in Java.
• Variable scope, lifetime and external access.
• Literals by data type, numeric data type ranges.
• Float versus packed.
• Boolean data type.
• Casting and numeric conversions.
• Java data type class wrappers.

Arrays and Vectors

• Reference variables and objects.
• Creating or instantiating arrays.
• Compile time and run time initialisation of arrays.
• Initialising multi-dimensional arrays.
• Vectors, simulating vectors in RPG.
• Using arrays instead of primitives for simulated pass by reference.

String Manipulation

• Java string basics and pitfalls.
• String manipulation - concatenation, substring, trimming, lengths, case translation, scanning.
• StringBuffer class.
• Tokenising strings, the string tokenizer class.
• String class; more methods.

Date and Time Manipulation

• RPG date and time review.
• Java date and time support.
• Date and time manipulation.
• Formatting and extracting date and time.
• Time zones, leap years.

Object Orientation Revisited

• Protected access, preventing or enforcing inheritance.
• Constructors and inheritance, multiple inheritance.
• Casting objects, common methods to override.
• Searching for objects; re-use considerations.

Exceptions

• OPM and ILE exception model overview.
• Exception objects in Java.
• Sending Java exceptions, monitoring for Java exceptions.
• User error messages versus Java exceptions.

Threads

• Threads; asynchronous versus synchronous.
• Spawning threads, stopping threads.
• Ending programs with Java running threads.
• Threaded application design.

User Interface

• User interfaces with RPG and Java compared.
• Buttons, lists, text, windows, frames, panels, menu bars, pull down menus, pop ups.
• Events; processing input, error checking, error messages.
• Applet versus application, Locales

Database Access

• Accessing data with Java, Java JDBC programming.
• Portability versus performance.
• Object oriented database access.

Miscellaneous

• Java supplied packages.
• Java Beans, servlets, enterprise beans.
• iSeries (AS/400) toolbox for Java.

Materials

This course has been developed by George Farr and Phil Coulthard of IBM Corporation, the authors of the book "Java for RPG Programmers" (Advice Press, ISBN 1-889671-23-1).

Delegates attending this course will receive copies of all handouts and exercises. The course includes numerous practical and written exercises to provide delegates with hands on practical experience in the use of the Java programming language.

Schedule