Beginning COBOL for Programmers by Coughlan, Michael -- Read -- Imperial Library of Trantor

Index

Cover Title Copyright Dedication Contents at a Glance Contents About the Author About the Technical Reviewer Acknowledgments Preface Chapter 1: Introduction to COBOL

What Is COBOL?

COBOL’s Target Application Domain COBOL’s Fitness for Its Application Domain

History of COBOL

Beginnings COBOL Standards

The Argument for COBOL (Why COBOL?)

Dominance of COBOL in Enterprise Computing Danger, Difficulty, and Expense of Replacing Legacy COBOL Applications Shortage of COBOL Programmers: Crisis and Opportunity COBOL: The Hidden Asset Advantages of Bespoke Software Characteristics of COBOL Applications Characteristics of COBOL

Summary References

Chapter 2: COBOL Foundation

COBOL Idiosyncrasies COBOL Syntax Metalanguage

Some Notes on Syntax Diagrams Example Metalanguage

Structure of COBOL Programs

Divisions

The Four Divisions

IDENTIFICATION DIVISION ENVIRONMENT DIVISION DATA DIVISION File Section Working-Storage Section Data Hierarchy PROCEDURE DIVISION Shortest COBOL Program

COBOL Coding Rules

Name Construction

Example Programs

The COBOL Greeting Program The DoCalc Program The Condition Names Program Chapter Exercise

Where to Get a COBOL Compiler

Micro Focus Visual COBOL OpenCOBOL Raincode COBOL Compileonline COBOL Fujitsu NetCOBOL

Summary References

Chapter 3: Data Declaration in COBOL

Categories of Program Data

COBOL Literals Data Items (Variables) Figurative Constants Elementary Data Items

Declaring Elementary Data Items

PICTURE Clause Symbols PICTURE Clause Notes Example Declarations

Assignment in COBOL

The MOVE Verb MOVE Syntax MOVE Rules MOVE Combinations MOVE Examples

Structured Data

Group Data Items Level Numbers Data Hierarchy Level-Number Relationships Govern Hierarchy

Summary

Chapter 4: Procedure Division Basics

Input and Output with ACCEPT and DISPLAY

The DISPLAY Verb The ACCEPT Verb Example Program: ACCEPT and DISPLAY

Arithmetic in COBOL

Common Arithmetic Template Nonconforming Arithmetic Verbs

Let’s Write a Program Summary

Chapter 5: Control Structures: Selection

Selection IF Statement Condition Types

Relation Conditions Class Conditions Sign Conditions Complex Conditions

Implied Subjects Nested IFs Delimiting Scope: END-IF vs. Period Condition Names

Defining Condition Names Using Condition Names Correctly Example Program Setting a Condition Name to True

EVALUATE

Decision Tables EVALUATE Metalanguage Notes EVALUATE Examples

Summary References

Chapter 6: Control Structures: Iteration

Paragraphs Revisited The PERFORM Verb

Open Subroutines Closed Subroutines COBOL Subroutines Why Use Open Subroutines? PERFORM NamedBlock How PERFORM Works PERFORM..THRU Dangers Using PERFORM..THRU Correctly

PERFORM..TIMES

Inline Execution Out-of-Line Execution

PERFORM..UNTIL

Notes on PERFORM..UNTIL How PERFORM..UNTIL Works

PERFORM..VARYING

Notes on PERFORM..VARYING How PERFORM..VARYING Works

Summary References

Chapter 7: Introduction to Sequential Files

What Is a File?

Terminology Files, Records, and Fields How Files Are Processed Implications of Buffers File and Record Declarations Creating a Record Declaring the Record Buffer in Your Program The SELECT and ASSIGN Clause SELECT and ASSIGN Syntax

Processing Sequential Files

The OPEN Statement The CLOSE Statement The READ Statement How READ Works The WRITE Statement

Summary

Chapter 8: Advanced Sequential Files

Files with Multiple Record Types

Problem Specification Implications of Files with Multiple Record Types Multiple Record Descriptions, One Record Buffer The Type Code

Printer Sequential Files

SELECT and ASSIGN What Is in a Report Problem of Multiple Print Records Solution to the Multiple Print Record Problem WRITE Syntax Revisited

Variable-Length Records

FD Entries for Variable-Length Records Notes on Varying-Length Records Example Program

Summary

Chapter 9: Edited Pictures

Edited Pictures Formatting Output

Immediate Editing Example Program

Types of Editing Editing Symbols Insertion Editing

Simple-Insertion Editing Special-Insertion Editing Fixed-Insertion Editing Floating Insertion

Suppression-and-Replacement Editing

Suppression-and-Replacement Examples

Example Print Lines

Immediate Editing

PICTURE String Restrictions The PICTURE Clause Scaling Symbol

Rules

Summary

Chapter 10: Processing Sequential Files

File Organization vs. Method of Access Sequential Organization

Ordered and Unordered Files

Control-Break Processing

Specifications that Require Control Breaks Detecting the Control Break Writing a Control-Break Program Control-Break Program Template Three-Level Control Break An Atypical Control Break

Updating Sequential Files

Applying Transactions to an Ordered Sequential File The File-Update Problem: Simplified

The Full File Update Problem

Full File Update Program Program Notes Test Data and Results

Summary

TestData Notes

Chapter 11: Creating Tabular Data

Tables vs. Arrays

Table/Array Definition Table/Array Differences

Declaring Tables

OCCURS Clause Rules Subscript Rules

Why Use Tabular Data?

First Specification Second Specification Using a Table for the State Sales Totals Third Specification: Group Items as Table Elements Tabular Data Program

Multidimensional Tables

Multidimensional Program Correct Depiction of COBOL Tables Three-Dimensional Tables

Prefilled Tables

REDEFINES Clause Creating Prefilled Tables of Values Creating a Prefilled Two-dimensional Table

ANS 85 Table Changes Summary

Specification Extension

Chapter 12: Advanced Data Declaration

The Redefines Clause

Specification: Aromamora Base Oil Sales Report

The REDEFINES Clause

REDEFINES Syntax REDEFINES Notes REDEFINES Examples

The RENAMES Clause

RENAMES Syntax RENAMES Notes RENAMES Examples Listing Notes

The USAGE Clause

Representation of Numeric Data Nonstandard USAGE Extensions

Decimal Arithmetic Summary

The Problems Program 1 Program 2 Program 3 Program 4

References

Chapter 13: Searching Tabular Data

SEARCHING Tabular Data Searching Using SEARCH and SEARCH ALL

INDEXED BY Clause Using SET to Manipulate the Table Index

The SEARCH Verb

SEARCH Examples Searching Multidimensional Tables Searching the First Dimension of a Two-Dimensional Table

The SEARCH ALL Verb

KEY IS Clause How a Binary Search Works SEARCH ALL

Variable-Length Tables Summary

Chapter 14: Sorting and Merging

SORTING

Simple Sorting Using Multiple Keys SORT with Procedures How an INPUT PROCEDURE Works OUTPUT PROCEDURE How the OUTPUT PROCEDURE Works Some Interesting Programs Sorting Tables: ISO 2002 Changes

Merging Files

MERGE Verb MERGE Notes Merging Province Sales Files

Summary

Chapter 15: String Manipulation

The INSPECT Verb

INSPECT INSPECT INSPECT: Format 3 INSPECT

String Concatenation

The STRING Verb String Concatenation Example

String Splitting

The UNSTRING Verb String-Splitting Program

Reference Modification Intrinsic Functions

Using Intrinsic Functions String Functions DATE Functions

Summary

Chapter 16: Creating Large Systems

Subprograms and the COPY Verb The CALL Verb

Parameter-Passing Mechanisms Subprograms State Memory and the IS INITIAL Phrase The CANCEL Verb The IS GLOBAL Clause The IS COMMON PROGRAM Clause Example Programs and Their Subprograms The IS EXTERNAL Clause Using IS EXTERNAL Data Items

The COPY Verb

The COPY Metalanguage How COPY Works How the REPLACING Phrase Works COPY Examples

Summary

Chapter 17: Direct Access Files

Direct Access vs.Sequential Files Organization of Relative Files Processing Relative Files

Reading a Relative File Creating a Relative File from a Sequential File Applying Transactions to a Relative File

Relative Files: Syntax and Semantics

Relative Files: SELECT and ASSIGN Clause Relative File Verbs

Organization of Indexed Files Processing Indexed Files

Reading an Indexed File Creating an Indexed File from a Sequential File Using Indexed Files in Combination Applying Transactions to an Indexed File

Indexed Files: Syntax and Semantics

Indexed Files: SELECT and ASSIGN Clause The Key of Reference Indexed File Verbs

Comparison of COBOL File Organizations

Sequential File Organization Relative File Organization Indexed File Organization

Summary Introduction

General Description Maintenance Procedure The Redundant Stock Report

Chapter 18: The COBOL Report Writer

Report Writer

Example Report: Solace Solar Solutions How the Report Writer Works Writing a Report Program Adding Features to the Report Program Adding More Features to the Report Program Report Writer Declaratives Report Writer Syntax and Semantics Special Report Writer Registers PROCEDURE DIVISION Report Writer Verbs

Declaratives

Using Declaratives with the Report Writer Using Declaratives with Files

Summary Introduction File Descriptions Print Specification

Chapter 19: OO-COBOL

Module Strength and Module Coupling Informational-Strength Modules in COBOL OO-COBOL

The UseDictionary Program The Dictionary Class

A Formal Introduction to OO-COBOL

Objects, Classes, and Methods Programming with Objects Registering a Class Declaring Object References Sending Messages to Instance Objects Creating a New Object Instance Destroying Objects Predefined Object Identifiers Writing Your Own Classes The Issue of Scope

Summary

Index

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