The local character set is the set of characters that can be entered or displayed in the command line shell of the client operating system. On the UNIX system, the local character set is controlled by the LANG environment variable. On Windows, it is controlled by settings in the Regional and Language Options.
In versions of Rational ClearQuest earlier than 7.0, write operations were not allowed unless the local character set matched the ClearQuest data code page. If the settings did not match, only read-only operations were allowed. Read-only mode was necessary because the ClearQuest applications used the local character set of the client or Web server to write data to the database instead of the ClearQuest data code page for the database set.
Beginning in version 7.0, Rational ClearQuest software processes data in Unicode, and its applications use the ClearQuest data code page to write to its databases. These applications can connect to the ClearQuest database in read/write mode even when the local character set does not match the ClearQuest data code page.
The vendor database character set for Oracle is referred to as character set or charset; for IBM DB2 as code page or code set, and for SQL Server as code page or collation.
Beginning in Rational ClearQuest version 7.1.1, you can select a UTF-8 ClearQuest data code page for Oracle and DB2 database sets. A UTF-8 data code page allows multilingual character storage in the user database. When you select UTF-8 as the data code page, you are working in a mixed local character set deployment unless the local code page of the operating system is also UTF-8. The latter is not an option on Windows systems.
Scripts and hooks written for a mixed local character set deployment or a UTF-8 multilingual database environment must handle ClearQuest character data that might not be included in the local character set. Those scripts and hooks must be coded to support Unicode to take full advantage of this capability in these environments.
The Designer includes a new setting: Unicode Aware. Hooks written for version 7.0 can specify whether characters in strings returned from ClearQuest API calls must be in the local character set only (RETURN_STRING_LOCAL) or can be any Unicode character (RETURN_STRING_UNICODE). Also, new API functions are available to control the return string mode. In RETURN_STRING_LOCAL mode, an API call returns an exception if the return string includes characters that cannot be represented in the local character set. In RETURN_STRING_UNICODE, an API call returns all characters without error.
To ensure that hooks and scripts handle all data in a mixed local character set or UTF-8 deployment, you must set the mode to RETURN_STRING_UNICODE and properly handle the Unicode characters that might be returned. Setting the return string mode to RETURN_STRING_UNICODE is not sufficient; you must verify that your code can handle Unicode characters correctly. The guidelines listed below are helpful, but ultimately, you must use the appropriate Unicode programming techniques for the scripting language.
If you are upgrading to version 7.0, these changes have no impact on an existing schema if all local character sets in the environment match the ClearQuest date code page, as was common in earlier versions. The default mode is RETURN_STRING_LOCAL, which allows hooks and scripts to continue to function.
If you are deploying version 7.0 into an environment in which local character sets do not match the ClearQuest data code page, you must ensure that your scripts can process Unicode character data for ClearQuest software, set the return mode for scripts to RETURN_STRING_UNICODE, and upgrade packages to version 7.0. For a list of the ClearQuest packages that support Unicode, see Table 1. Scripts that do not handle Unicode can run, but an error is returned if the system attempts to return to the script any character data that is not included in the local character set. These scripts continue to work as long as the data that they process is restricted to the local character set of the client or Web server.
Package | Return string mode |
---|---|
AMWorkActivitySchedule | RETURN_STRING_UNICODE |
ATStateTypes | RETURN_STRING_UNICODE |
Attachments | RETURN_STRING_UNICODE |
AuditTrail | RETURN_STRING_UNICODE |
BTStateTypes | RETURN_STRING_UNICODE |
BuildTracking | RETURN_STRING_UNICODE |
CQTM | RETURN_STRING_UNICODE |
Customer | RETURN_STRING_UNICODE |
DeploymentTracking | RETURN_STRING_UNICODE |
DTStateTypes | RETURN_STRING_UNICODE |
RETURN_STRING_UNICODE | |
EnhancementRequest | RETURN_STRING_UNICODE |
eSignature | RETURN_STRING_UNICODE |
History | RETURN_STRING_UNICODE |
Notes | RETURN_STRING_UNICODE |
Project | RETURN_STRING_UNICODE |
Resolution | RETURN_STRING_UNICODE |
TPM | RETURN_STRING_UNICODE |
ClearQuest software handles all data as Unicode characters. However, schema hooks (Perl and Visual Basic) and other ClearQuest API applications or integrations might not be coded to process Unicode characters. In version 7.0, a return string mode is available to handle this problem. Hook code can be set to Unicode Aware in the Designer script editor to indicate that the script runs in the RETURN_STRING_UNICODE return string mode. (To do so, select the Unicode Aware check box). Scripts can call the SetPerlReturnStringMode or SetBasicReturnStringMode method to set the return string mode to RETURN_STRING_UNICODE.
The return string mode restricts (RETURN_STRING_LOCAL) or allows full (RETURN_STRING_UNICODE) character representation when strings are returned by the ClearQuest API for Perl or COM.
It is a good practice to write hooks and scripts that can process Unicode characters. RETURN_STRING_LOCAL is provided as the default return string mode so that existing hooks and scripts for earlier versions of ClearQuest software can run without change. Over time, you should modify existing hooks and scripts to function in RETURN_STRING_UNICODE mode, even if you currently have no need for Unicode.
By default, an exception is thrown in step 2 when the ClearQuest API script returns with a string that includes characters outside the local character set. The exception prevents data corruption. After you review and confirm that the code can process Unicode characters, you can set the RETURN_STRING_UNICODE return string mode by using the ClearQuest API or in the script editor of the Designer. By making this change, in step 2 the ClearQuest API for Perl returns the field value string as UTF8 (UNICODE) if the string contains nonlocal character set data, and the ClearQuest API for VBScript, Visual Basic or COM returns unrestricted Unicode characters. Characters that cannot be represented in the local character set can then be returned to the hook or script for processing as Unicode characters.
In the RETURN_STRING_LOCAL mode, operations such as running queries can be performed and the query result sets can include Unicode characters. An exception is generated only if data is extracted from that result set by a Rational ClearQuest API method and the characters returned from the API call are not in the local character set. For example, an integration or external application can operate on a change request if the data that is passed back to the integration contains only local character set characters. The integration code must handle the exception thrown by a Rational ClearQuest API method when the characters returned are not in the local character set. If the integration API is configured as RETURN_STRING_UNICODE, the exception is not thrown but the application must correctly handle any Unicode character that is returned. In both the RETURN_STRING_LOCAL and RETURN_STRING_UNICODE modes, exceptions are also returned to the calling integration or application if the application writes characters that cannot be represented in the ClearQuest data code page.
For more information, see Setting the return string mode for hooks and scripts in the IBM Rational ClearQuest API Reference help.
Some packages or schemas are not designed to handle Unicode and nonlocal character set data. The support that each script in each package offers is indicated in the Designer script editor (the Unicode Aware check box is selected). The DefectTracking and Common schemas support Unicode. However, any schema that includes a package that does not support Unicode characters cannot be used in a mixed character set deployment. See Table 1.
You can edit or add hooks that access package fields, and these hooks are considered part of the package. Those hooks inherit the default Unicode support from the package, but the Designer does not display this correct setting for the hook.
If the local character sets of all clients connected to a database set or clan match the data code page, you do not need to consider these issues. For more information about character representations and code page settings, see the Administering Rational ClearQuest online help.