ILE Condition Handlers

ILE Condition Handlers

ILE condition

handlers

are

exception

handlers that

are registered

at

run

using the

Register

ILE

Condition

Handler (CEEHDLR)

bindable API.

They

are

to handle, percolate or promote exceptions. The exceptions are present condition handlers in the form of an ILE condition. You can register mo ILE condition handler. ILE condition handlers may be unregistered by c

Unregister

ILE Condition Handler

(CEEHDLU) bindable

API.

 

There

are

several reasons why

you

might want to use

an ILE condition

¹ You

can bypass language-specific

handling by

handling the exception

own

handler.

 

 

 

 

This enables you to provide the same exception handling mechanism in application with modules in different ILE HLLs.

¹ You can use this API to scope exception handling to a call stack e

The ILE bindable API CEEHDLR is scoped to the invocation that contain remains in effect until you unregister it, or until the procedure r

Note: Any

call

to

the CEEHDLR API from any

detail, total or subroutine

lation will make the condition handler active for the

entire

pr

including

all

input, calculation, and output operations.

However,

i

not

affect

subprocedures, nor will

a subprocedure

calling CEEHDLR

 

affect the main procedure.

 

If

a subprocedure is called

recursively, only the invocation that

is

affected by it. If you want

the condition handler active for

then

CEEHDLR must be called by

each

invocation.

For information on how to use ILE condition handlers,ILE Conceptsrefer. to

Using a Condition Handler

The following example shows you how to:

1. Code a condition handler to handle the RPG 'out-of-bounds' error

2.Register a condition handler

3.Deregister a condition handler

4.Code a *PSSR error subroutine.

The example consists of two procedures:

¹RPGHDLR, which consists of a user-written condition handler for out-of substring errors

¹SHOWERR, which tests the RPGHDLR procedure.

 

While SHOWERR is designed primarily to show how RPGHDLR works, the two

 

procedures

combined are

also

useful for determining 'how' ILE exception

 

works. Both procedures write to QSYSPRT the 'actions' which occur as th

 

processed.

You

might

want

to

modify these

procedures

in

order to

si

 

aspects

of

ILE

exception

handling

which

you

would

like

to

explore.

 

 

Figure 116

on page 239

shows

the

source

for

the

procedure RPGHDLR.

Th

cedure

defines

three procedure

parameters: an

ILE

condition token

st

238 ILE RPG for AS/400 Programmer's Guide

Page 262
Image 262
IBM AS/400 manual ILE Condition Handlers, Using a Condition Handler, Condition token

AS/400 specifications

The IBM AS/400, now known as the IBM iSeries, is a midrange computer system that has been a cornerstone of enterprise computing since its introduction in 1988. Designed to provide a robust platform for business applications, the AS/400 is celebrated for its reliability, scalability, and integrated database capabilities.

One of the key features of the AS/400 is its Integrated Operating Environment, which blends hardware and software resources seamlessly. This integration allows businesses to execute diverse workloads, ranging from traditional applications to modern web-based services, all on a single platform. The operating system, OS/400 (now IBM i), offers a rich set of APIs and tools for developers, simplifying application development and management.

Another standout characteristic of the AS/400 is its built-in database, DB2 for i. This powerful relational database management system allows for efficient data handling and provides advanced features such as support for SQL, XML, and JSON, making it easier for businesses to manage their data and integrate it with other systems. The database's tight integration with the operating system enables high performance and security.

In terms of scalability, the AS/400 can accommodate small businesses as well as large enterprises, with the ability to support hundreds of users simultaneously. Its architecture allows for easy upgrades in hardware, meaning that organizations can scale their systems without replacing the entire infrastructure.

Security is another critical attribute of the AS/400. With a sophisticated security model, it offers built-in user authentication, access control, encryption, and auditing capabilities to protect data and applications from unauthorized access.

The AS/400 also supports multiple programming languages, including RPG, COBOL, Java, and PHP, giving organizations the flexibility to choose the development tools that best fit their needs. This diversity helps maintain legacy applications while also developing new ones that leverage modern technologies.

Moreover, the platform supports both traditional green-screen interfaces and modern graphical user interfaces, allowing organizations to transition smoothly into contemporary user experience paradigms.

Overall, the IBM AS/400 stands out as a resilient, flexible, and secure computing platform that enables organizations to effectively manage their business operations, streamline processes, and adapt to changing market demands. Its unique combination of integrated features and capabilities ensures that it remains relevant in today's fast-paced technology landscape.