MainframeMaster

COBOL Data Exchange

Data exchange enables communication and data transfer between different systems, programs, and formats. Learn to implement data exchange protocols, handle different formats, and ensure reliable data communication.

Data Exchange Formats

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       WORKING-STORAGE SECTION.
       01 EXCHANGE-FORMATS.
           05 FORMAT-TYPE PIC X.
               88 FIXED-FORMAT VALUE 'F'.
               88 DELIMITED-FORMAT VALUE 'D'.
               88 XML-FORMAT VALUE 'X'.
               88 JSON-FORMAT VALUE 'J'.
           05 FORMAT-DESCRIPTION PIC X(20).
       
       PROCEDURE DIVISION.
       EVALUATE FORMAT-TYPE
           WHEN FIXED-FORMAT
               PERFORM PROCESS-FIXED-FORMAT
           WHEN DELIMITED-FORMAT
               PERFORM PROCESS-DELIMITED-FORMAT
           WHEN XML-FORMAT
               PERFORM PROCESS-XML-FORMAT
           WHEN JSON-FORMAT
               PERFORM PROCESS-JSON-FORMAT
       END-EVALUATE.

Support multiple data exchange formats including fixed-length records, delimited files, XML, and JSON. Choose appropriate formats based on system requirements, data complexity, and compatibility needs.

Fixed-Length Record Exchange

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       WORKING-STORAGE SECTION.
       01 FIXED-RECORD.
           05 RECORD-TYPE PIC X VALUE 'C'.
           05 CUSTOMER-ID PIC 9(6).
           05 CUSTOMER-NAME PIC X(30).
           05 CUSTOMER-BALANCE PIC 9(9)V99.
           05 FILLER PIC X(10).
       
       PROCEDURE DIVISION.
       *> Write fixed-length record
       MOVE 'C' TO RECORD-TYPE
       MOVE 123456 TO CUSTOMER-ID
       MOVE 'JOHN SMITH' TO CUSTOMER-NAME
       MOVE 1500.50 TO CUSTOMER-BALANCE
       MOVE SPACES TO FILLER
       WRITE EXCHANGE-RECORD.
       
       *> Read fixed-length record
       READ EXCHANGE-FILE
           AT END SET EOF TO TRUE
           NOT AT END
               DISPLAY 'Record Type: ' RECORD-TYPE
               DISPLAY 'Customer ID: ' CUSTOMER-ID
               DISPLAY 'Customer Name: ' CUSTOMER-NAME
               DISPLAY 'Balance: ' CUSTOMER-BALANCE
           END-READ.

Use fixed-length records for structured data exchange. Define record layouts with specific field positions and sizes. This format provides efficient processing and predictable data structure.

Delimited Data Exchange

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       WORKING-STORAGE SECTION.
       01 DELIMITED-RECORD PIC X(200).
       01 PARSED-FIELDS.
           05 FIELD-1 PIC X(20).
           05 FIELD-2 PIC X(30).
           05 FIELD-3 PIC X(15).
           05 FIELD-4 PIC X(25).
       
       PROCEDURE DIVISION.
       *> Parse delimited record (CSV format)
       UNSTRING DELIMITED-RECORD
           DELIMITED BY ','
           INTO FIELD-1 FIELD-2 FIELD-3 FIELD-4
       END-UNSTRING
       
       *> Create delimited record
       STRING FIELD-1 ',' FIELD-2 ',' FIELD-3 ',' FIELD-4
           INTO DELIMITED-RECORD
       END-STRING.

Handle delimited data formats like CSV using UNSTRING and STRING statements. Parse incoming delimited data into individual fields and create delimited output for other systems.

Character Set Conversion

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       WORKING-STORAGE SECTION.
       01 CHARACTER-SET-CONVERSION.
           05 SOURCE-DATA PIC X(100).
           05 TARGET-DATA PIC X(100).
           05 CONVERSION-TYPE PIC X.
               88 EBCDIC-TO-ASCII VALUE 'E'.
               88 ASCII-TO-EBCDIC VALUE 'A'.
       
       PROCEDURE DIVISION.
       EVALUATE CONVERSION-TYPE
           WHEN EBCDIC-TO-ASCII
               PERFORM CONVERT-EBCDIC-TO-ASCII
           WHEN ASCII-TO-EBCDIC
               PERFORM CONVERT-ASCII-TO-EBCDIC
       END-EVALUATE.
       
       CONVERT-EBCDIC-TO-ASCII.
           *> Convert EBCDIC to ASCII for data exchange
           PERFORM VARYING I FROM 1 BY 1 UNTIL I > FUNCTION LENGTH(SOURCE-DATA)
               MOVE FUNCTION CHAR(SOURCE-DATA(I:1)) TO TARGET-DATA(I:1)
           END-PERFORM.

Handle character set conversions between EBCDIC (mainframe) and ASCII (distributed systems). Implement conversion procedures to ensure proper data representation across different platforms.

Data Validation and Transformation

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       VALIDATE-EXCHANGE-DATA.
           MOVE 'Y' TO VALIDATION-FLAG
           
           *> Validate record structure
           IF RECORD-TYPE NOT = 'C' AND RECORD-TYPE NOT = 'A'
               DISPLAY 'Error: Invalid record type: ' RECORD-TYPE
               MOVE 'N' TO VALIDATION-FLAG
           END-IF.
           
           *> Validate data fields
           IF CUSTOMER-ID = 0 OR CUSTOMER-ID > 999999
               DISPLAY 'Error: Invalid customer ID: ' CUSTOMER-ID
               MOVE 'N' TO VALIDATION-FLAG
           END-IF.
           
           *> Transform data if needed
           IF VALIDATION-FLAG = 'Y'
               PERFORM TRANSFORM-DATA-FOR-TARGET-SYSTEM
           END-IF.
       
       TRANSFORM-DATA-FOR-TARGET-SYSTEM.
           *> Convert data format for target system
           MOVE FUNCTION UPPER-CASE(CUSTOMER-NAME) TO CUSTOMER-NAME
           COMPUTE CUSTOMER-BALANCE = CUSTOMER-BALANCE * 100  *> Convert to cents
           MOVE FUNCTION CURRENT-DATE TO LAST-UPDATED.

Implement comprehensive data validation and transformation for data exchange. Validate data integrity, format, and business rules before exchange. Transform data formats to meet target system requirements.

Error Handling and Recovery

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       WORKING-STORAGE SECTION.
       01 EXCHANGE-ERROR-HANDLING.
           05 RETRY-COUNT PIC 9(2) VALUE 0.
           05 MAX-RETRIES PIC 9(2) VALUE 3.
           05 ERROR-TYPE PIC X(20).
           05 ERROR-MESSAGE PIC X(100).
       
       PROCEDURE DIVISION.
       PERFORM EXCHANGE-DATA WITH RETRY
       IF EXCHANGE-SUCCESSFUL = 'N'
           PERFORM HANDLE-EXCHANGE-FAILURE
       END-IF.
       
       EXCHANGE-DATA-WITH-RETRY.
           PERFORM UNTIL EXCHANGE-SUCCESSFUL = 'Y' OR RETRY-COUNT >= MAX-RETRIES
               ADD 1 TO RETRY-COUNT
               PERFORM ATTEMPT-DATA-EXCHANGE
               IF EXCHANGE-SUCCESSFUL = 'N'
                   PERFORM WAIT-BEFORE-RETRY
               END-IF
           END-PERFORM.

Implement robust error handling and recovery mechanisms for data exchange. Use retry logic with exponential backoff, comprehensive error logging, and fallback procedures for failed exchanges.

Data Exchange Protocols

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       WORKING-STORAGE SECTION.
       01 EXCHANGE-PROTOCOL.
           05 PROTOCOL-TYPE PIC X.
               88 FILE-TRANSFER VALUE 'F'.
               88 MESSAGE-QUEUE VALUE 'M'.
               88 DATABASE-LINK VALUE 'D'.
               88 WEB-SERVICE VALUE 'W'.
           05 PROTOCOL-PARAMETERS.
               10 TIMEOUT-VALUE PIC 9(4) VALUE 300.
               10 RETRY-COUNT PIC 9(2) VALUE 3.
               10 BATCH-SIZE PIC 9(4) VALUE 100.
       
       PROCEDURE DIVISION.
       EVALUATE PROTOCOL-TYPE
           WHEN FILE-TRANSFER
               PERFORM FILE-BASED-EXCHANGE
           WHEN MESSAGE-QUEUE
               PERFORM MESSAGE-QUEUE-EXCHANGE
           WHEN DATABASE-LINK
               PERFORM DATABASE-EXCHANGE
           WHEN WEB-SERVICE
               PERFORM WEB-SERVICE-EXCHANGE
       END-EVALUATE.

Support multiple data exchange protocols including file transfer, message queues, database links, and web services. Choose appropriate protocols based on system requirements and data characteristics.

Data Exchange Monitoring

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       WORKING-STORAGE SECTION.
       01 EXCHANGE-MONITORING.
           05 EXCHANGE-STATISTICS.
               10 RECORDS-SENT PIC 9(8) VALUE 0.
               10 RECORDS-RECEIVED PIC 9(8) VALUE 0.
               10 EXCHANGE-ERRORS PIC 9(6) VALUE 0.
               10 LAST-EXCHANGE-TIME PIC 9(8).
           05 PERFORMANCE-METRICS.
               10 EXCHANGE-DURATION PIC 9(6).
               10 RECORDS-PER-SECOND PIC 9(6).
       
       PROCEDURE DIVISION.
       PERFORM MONITOR-EXCHANGE-PERFORMANCE
       IF RECORDS-PER-SECOND < PERFORMANCE-THRESHOLD
           DISPLAY 'Warning: Exchange performance below threshold'
           PERFORM INVESTIGATE-PERFORMANCE-ISSUE
       END-IF.

Implement comprehensive monitoring for data exchange operations. Track statistics, performance metrics, error rates, and throughput. Use monitoring data to optimize exchange processes and identify issues.

Data Encryption

Data security and protection

Communication Handling

Inter-program communication