Regular expressions

Tivoli Netcool/OMNIbus supports the use of regular expressions in search queries that you perform on ObjectServer data. Regular expressions are sequences of atoms that are made up of normal characters and metacharacters.

An atom is a single character or a pattern of one or more characters in parentheses. Normal characters include uppercase and lowercase letters, and numbers. Metacharacters are non-alphabetic characters that possess special meanings in regular expressions.

Two types of regular expression libraries are available for use with the ObjectServer:

• NETCOOL: This library is useful for single-byte character processing.
• TRE: This library enables use of the POSIX 1003.2 extended regular expression syntax, and provides support for both single-byte and multi-byte character languages. When the UTF-8 encoding is enabled on Windows, only the characters within Unicode plane 0, the Basic Multilingual Plane (BMP), are supported in regular expression patterns. Any character outside of the BMP, which is found in the pattern, will result in an error. The matching strings for the regular expression pattern can contain any UTF-8 character.
  Note: Use of the TRE library can lead to a marked decrease in system performance. Optimal system performance is achieved with the NETCOOL library.

You can use the ObjectServer property RegexpLibrary to specify which library should be used for regular expression matching. The NETCOOL regular expression library is enabled by default.