Previous | Table of Contents | Next |
Translating the pseudocode for the package into code is fairly straightforward. Listing 6.14 contains the package spec and the package body for the System_Errors package.
Listing 6.14 The package spec for the System_Errors package.
PACKAGE System_Errors IS DELIMITER CONSTANT char (1) := '^'; PROCEDURE Build_Error (vModule IN varchar2, vProcName IN varchar2, iErrorNum IN integer, vDataString IN varchar2, vDisplayFlag IN varchar2); PROCEDURE Next_Word (vDataString IN OUT varchar2, vWord OUT varchar2); END System_Errors; PACKAGE BODY System_Errors -- ****************************************************************** iNextPart integer := 1; -- ****************************************************************** FUNCTION Next_String (vModule IN varchar2, iErrorNum IN integer) RETURN varchar2 IS vNextStringPart ERROR_MESSAGES.error_text%TYPE; BEGIN SELECT error_text INTO vNextStringPart FROM ERROR_MESSAGES WHERE module_name = vModule AND error_number = iErrorNum AND error_part = iNextPart; iNextPart := iNextPart + 1; RETURN vNextStringPart; END Next_String; -- ****************************************************************** PROCEDCURE Build_Error (vModule IN varchar2, vProcName IN varchar2, iErrorNum IN integer, vDataString IN varchar2, vDisplayFlag IN varchar2) IS MODULE CONSTANT varchar2 (6) := 'ERRORS'; PROCEDURE CONSTANT varchar2 (30) := 'Build_Error'; UNKNOWN_ERROR CONSTANT integer := 1; bRecursion boolean := FALSE; iSeverity integer; vDataString varchar2 (200); vNewMessage varchar2 (200); vNextPart ERROR_MESSAGES.error_text%TYPE; vNextWord varchar2 (30); xRECURSION_ERROR EXCEPTION; BEGIN IF NOT bRecursion THEN bRecursion := FALSE; END IF; vDataWords := vDataString; vNewMessage := NULL; iNextPart := 1; -- -- If the module that was specified doesn't exist or the error for -- the module can't be found, write an "UNKNOWN ERROR" message -- here. This is combined with the retrieval of the severity_level -- for the message. -- BEGIN SELECT severity_level INTO iSeverity FROM ERROR_SEVERITIES WHERE module_name = vModule AND error_number = iErrorNum; EXCEPTION WHEN NO_DATA_FOUND THEN IF NOT bRecursion THEN bRecursion := TRUE; Build_Error (vModule => MODULE, vProcName => PROCEDURE, iErrorNum => UNKNOWN_ERROR, vDataString => vModule DELIMITER iErrorNum DELIMITER vProcName DELIMITER, vDisplayFlag => 'Y'); ELSE RAISE xRECURSION_ERROR; END IF; END; -- -- Get the first part of the error message from the ERROR_MESSAGES -- table. -- vNextPart := Next_String (vModule => vModule, iErrorNum => iErrorNum); vNewMessage := vNewMessage vNextPart; WHILE (instr (vDataString, DELIMITER) > 0) LOOP -- -- Get the next piece of data from the string. -- Next_Word (vDataString => vDataWords, vWord => vNextWord); -- -- Put the next piece of the error message onto the -- new message. -- vNextPart := Next_String (vModule => vModule, iErrorNum => iErrorNum); vNewMessage := vNewMessage vNextWord vNextPart; END LOOP; INSERT INTO SYSTEM_ERRORS (error_number, error_time, error_text, displayed) VALUES (ERROR_SEQ.nextval, SYSDATE, vNewMessage, vDisplayFlag); END Build_Error; -- ****************************************************************** PROCEDURE Next_Word (vDataString IN OUT varchar2, vWord OUT varchar2) IS BEGIN iDelimiterPos := instr (vDataString, DELIMITER); vWord := substr (vDataString, 1, iDelimiterPos); vDataString := substr (vDataString, (iDelimiterPos + 1)); END Next_Word; END System_Errors;
In reality, packages are not tested; procedures and functions within the package are tested individually from the lowest point on the food chain to the highest. Testing a package requires every subroutine inside the package to be tested thoroughly. References to global variables , constants, and other constructs should be closely examined during the test.
Testing private procedures and functions is somewhat difficult. It s often easier to test procedures and functions by making them public for testing purposes, then removing the public definition of the object from the package spec and then testing the security of the private object.
Chapter 6 has discussed the fundamentals of grouping procedures and functions using packages. At this point, you should be familiar with the creation of packages and have some insights into designing your own packages and testing the routines inside a package.
Previous | Table of Contents | Next |