After migrating to Integration Server 10.15, regular expressions might not work as expected or expression evaluation might end with a java.util.regex.PatternSyntaxException.Prior to version 10.15, Integration Server used the Jakarta ORO Java classes from Apache to provide Perl 5 pattern matching when evaluating regular expressions. This was the default behavior. Integration Server 10.11 and earlier also provided a server configuration parameter to use the Java regular expression pattern matching behavior defined in the java.util.regex.Pattern class.

Integration Server 10.15 GA (General Availability) always performs Java regular expression pattern matching as described in the java.util.regex.Pattern class because Integration Server 10.15 GA does not include the Jakarta ORO libraries. (The Jakarta ORO project was retired by Apache in September 2010.) However, some Perl 5 constructs are not supported by java.util.regex.Pattern. Consequently, for solutions migrated to Integration Server 10.15, regular expressions that relied on the Perl 5 pattern matching might no longer evaluate successfully. Integration Server might exhibit unexpected behavior during regular expression evaluation, such as ending with a java.util.regex.PatternSyntaxException.

Note: The java.util.regex.Pattern class API documentation can be found here: https://docs.oracle.com/en/java/javase/11/docs/api/index.html

The section “Comparison to Perl 5” identifies Perl 5 constructs that are not supported by java.util.regex.Pattern. Keep in mind that there could be issues that are not described in the documentation.

To provide backward compatibility with regular expressions that rely on the Perl 5 pattern matching behavior, Integration Server 10.15 with fix IS_10.15_Core_Fix4 and higher applied now includes the Jakarta ORO libraries. After applying a fix that includes PIE-80824 (IS_10.15_Core_Fix4 and higher), Integration Server uses the Perl 5 regular expression pattern matching by default.

Integration Server now includes the server configuration parameter watt.server.usejavaregex to switch between the Perl 5 pattern matching provided by the Jakarta ORO libraries and the Java regular expression pattern matching provided in the java.util.regex.Pattern class.

watt.server.usejavaregex

Specifies whether pattern matching for regular expressions is done using Java regular expression pattern matching or Perl 5 pattern matching. Set watt.server.usejavaregex to true to use the Java regular expression pattern matching provided in the java.util.regex.Pattern class. Set watt.server.usejavaregex to false to use the Perl 5 pattern matching provided by the Jakarta ORO libraries. The default is false.

Integration Server does not need to be restarted for changes to this parameter to take effect.

Note: The Jakarta ORO project was retired by Apache in September 2010 because there were not any new features or releases planned. Software AG strongly recommends modifying regular expressions that relied on Perl 5 pattern matching to use Java regular expressions.