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You can go to: http://publib.boulder.ibm.com/iseries/v5r1/ic2924/index.htm? and see all this information you need. In addition, I have I have few notes here: The improvements to RPG IV in V5R1 are so substantial that some have taken to calling it RPG V. And when the new features are used to their full potential, V5R1 RPG programs can look like a different language. The major enhancements to RPG IV since V4R4 are easier interfacing with Java?, new built-in functions, free form calculation specifications, control of which file is opened, qualified subfield names, and enhanced error handling. RPG: Improved support for calls between Java and ILE RPG using the Java Native Interface (JNI) A new data type: Object A new definition specification keyword: CLASS The LIKE definition specification keyword has been extended to support objects. The EXTPROC definition specification keyword has been extended to support Java procedures. New status codes. RPG: New BIFs Functions for converting a number into a duration that can be used in arithmetic expressions: %MSECONDS, %SECONDS, %MINUTES, %HOURS, %DAYS, %MONTHS, and %YEARS. The %DIFF function, for subtracting one date, time, or timestamp value from another. Functions for converting a character string (or date or timestamp) into a date, time, or timestamp: %DATE, %TIME, and %TIMESTAMP. The %SUBDT function, for extracting a subset of a date, time, or timestamp. RPG: New BIFs Functions for allocating or reallocating storage: %ALLOC and %REALLOC. Functions for finding an element in an array: %LOOKUP, %LOOKUPGT, %LOOKUPGE, %LOOKUPLT, and %LOOKUPLE. Functions for finding an element in a table: %TLOOKUP, %TLOOKUPGT, %TLOOKUPGE, %TLOOKUPLT, and %TLOOKUPLE. Functions for verifying that a string contains only specified characters (or finding the first or last exception to this rule): %CHECK and %CHECKR The %XLATE function, for translating a string based on a list of from-characters and to-characters. The %OCCUR function, for getting or setting the current occurrence in a multiple-occurrence data structure. The %SHTDN function, for determining if the operator has requested shutdown. The %SQRT function, for calculating the square root of a number. RPG: FREE /END-FREE directives The new /FREE and its closing directive /END-FREE allow you to isolate a set of source statements, much like the /EXEC SQL and /END-EXEC directives do.?/FREE and /END-FREE, however identify a non-columnar operation code area. That is yet a 3rd Calculation specification. No specification type in column 6--it must be blank. End every statement with a semi colon ( ; ). The EVAL operation code name itself is optional: X = A + B /C; EVAL X = A + B / C; Statement continuation is implied except for broken literal values or extended names Most Operation codes can be specified. When using traditional operation codes, reverse Factor 1 and the OpCode location That is:? CHAIN keyvalue? file-name Let's look as how many different techniques there are for doing an ADD operation in RPG IV: 1) Traditional long-form ADD operation code: C COST ADD MARKUP PRICE 2) Traditional short-form ADD operation code: C Z-ADD COST PRICE C ADD MARKUP PRICE 3) Contemporary EVAL operation code: C EVAL PRICE = COST + MARKUP 4) Contemporary EVAL operation code enclosed in /FREE /END-FREE directives: /FREE Eval Price = Cost + MarkUp; /END-FREE 5) EVAL operation code enclosed in /FREE /END-FREE directives without specifying the OpCode name: /FREE Price = Cost + MarkUp; /END-FREE RPG: Exception Handling The MONITOR operation It sets up an event handler for a monitored group of statements. This event handler works similar to a MONMSG command in CL. It establishes a block of code (group of RPG statements) that are run when an error occurs within the monitored group. To set up a monitored group, you type the MONITOR operation code, then follow it with the statements for which the monitoring applies. Then, after the final statement in the monitor group, type the ON-ERROR operation with the RPG Status Code error ID in Factor 2. These are the same status codes found in the *STATUS position of the INFDS and PSDS data structures, and in the contemporary %STATUS built-in function. ON-ERROR - Set Up Event Monitor You can specify one or more status codes with the ON-ERROR operation. This is similar to using a MONMSG command in CL with multiple message IDs specified. As always in RPG IV, you separate multiple status code with a colon. There are three identifiers that you can use to create a more generic handler. In place of a specific status code, specify *PROGRAM to indicate that any program status code (i.e., those in the range of 1000 to 9999) are monitored, or *FILE to indicate that any file-related status code (i.e., those in the range of 100 to 999) are monitored. Optionally, you can specify *ALL for the status code that, obviously, monitors for any status code to occur. RPG: Data Structures A new definition specification keyword: QUALIFIED. This keyword specifies that subfield names will be qualified with the data structure name. A new definition specification keyword: LIKEDS. This keyword specifies that subfields are replicated from another data structure. The subfield names will be qualified with the new data structure name. LIKEDS is allowed for prototyped parameters; it allows the parameter's subfields to be used directly in the called procedure. The INZ definition specification keyword has been extended to allow a data structure to be initialized based on its parent data structure. These keywords and enhancements offer several benefits: Subfields in different data structures can have the same name. It's clear when you're dealing with subfields within calculation. You can specify data structures easily as parameters to procedures. RPG: Softcoded Filenames (EXTFILE and EXTMBR Keywords) A common coding technique is to code USROPN for a file, call QCMDEXC to override the file to a specific external file, then open the file. Now you can use the EXTFILE and EXTMBR keywords to control which external file gets opened. RPG: ELSEIF (Else clause with an IF statement) This operation code consolidates the ELSE and the IF opcodes by integrating their function into one ELSEIF operation.? Factor 2 of the ELSEIF operation supports everything the traditional IF operation supports. So now, instead of coding an ELSE opcode on one line, and an IF opcode on a second line, you can code one ELSEIF operation to handle the situation. But the ELSEIF goes one step further. It eliminates the requirement to code a closing ENDIF opcode. Unlike the IF opcode which requires a corresponding ENDIF opcode to close the IF condition, an ELSEIF uses the same ending ENDIF operation that the opening IF operation uses. That is, only one closing ENDIF statement is needed!. In fact, this effectively does the same kind of function as the SELECT / WHEN / OTHER / ENDSL operation. RPG: Other Enhancements The following /DEFINE names are predefined: *VnRnMn, *ILERPG, *CRTBNDRPG, and *CRTRPGMOD. The search string in a %SCAN operation can now be longer than string being searched. (The string will not be found, but this will no longer generate an error condition.) The DUMP operation code now supports the A extender, which means that a dump is always produced - even if DEBUG(*NO) was specified. A new directive, /INCLUDE, is equivalent to /COPY except that /INCLUDE is not expanded by the SQL preprocessor. Included files cannot contain embedded SQL or host variables. RPG: Other Enhancements The OFLIND file-specification keyword can now take any indicator, including a named indicator, as an argument. The LICOPT (licensed internal code options) keyword is now available on the CRTRPGMOD and CRTBNDRPG commands. The PREFIX file description keyword can now take an uppercase character literal as an argument. The literal can end in a period, which allows the file to be used with qualified subfields. The PREFIX definition specification keyword can also take an uppercase character literal as an argument. This literal cannot end in a period. The parameter to the DIM, OCCURS, and PERRCD keywords no longer needs to be previously defined. HTH!!! Peter Vidal Pall Aeropower Corp. SR Programmer Analyst WWW.Pall.com / 727-539-8448, x2414 "A good player makes himself look good; a great player makes the team look good." Author unknown
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