The regular expressions that you can use in the search and replace dialogs and in places
like the 'Feature' attributes, the 'Primary index' of an
'Item' node or in checks all use standard Java
regexp syntax. Before QF-Test version 3.1 the default was the GNU regexp package (see also
appendix E). It can still be activated via the option Use old-style GNU regexps (from before QF-Test version 3.1). One major difference between the two is that '{' and '}' are
special characters that need to be escaped with '\' for Java regexps, but normal
characters for GNU:
Detailed regexp documentation with links to further information and even a whole book
about regular expressions are provided in the Java documentation for the class
java.util.regex.Pattern at http://download.oracle.com/javase/1.4.2/docs/api/java/util/regex/Pattern.html.
It's also worth to have a look at the Wikipedia article
about regular expressions.
Following is a short summary of the basics:
-
A '.' stands for any one character except line breaks. With the new Java regexps you
can start your regexp with the embedded flag '(?s)' to treat multi-line text like a
single line so '.' will match everything. The old GNU regexps have no such flag, so
you need to use '(.|\n)' to match everything. Unfortunately this expression causes a
StackOverflowException with Java regexps, so if QF-Test finds this
expression in any regular expression it will treat it as a GNU regexp regardless of
the option setting.
-
Character in between '[' and ']' match any one of these characters.
-
A '?' says the preceding element is optional, i.e. it may appear 0
or 1 times.
-
'+' means at least one of the preceding element.
-
'*' means 0 or more of the preceding element.
-
A group is created with '(' and ')'. A '?', '+' or '*' after the
closing brace refers to the whole group. All groups in a regexp
are numbered in the order of their opening brace. The first group
has the number 1, 0 stands for the whole regexp. For search and
replace,
$n in the replacement string expands to the
part of the original value matched by the nth
group. Example: To change the extension of file names starting
with /tmp/ from .foo to
.bar, search for (/tmp/.*)\.foo and
replace with $1.bar.
-
A '|' separates alternatives in a group.
-
'\' quotes to suppress the special meaning of the following
character or introduces special characters, e.g. '\n' for LineFeed
(a line break), '\r' for CarriageReturn (not needed for QF-Test,
see section 36.5) or '\t' for Tab.
Examples:
-
To match any text that contains the word 'tree' use
'.*tree.*'.
-
To match arbitrary text possibly including line breaks:
'(?s).*' for Java
regexps and '(.|\n)*' for GNU.
-
To replace 'tree' in arbitrary text with 'node' use
'(.*)tree(.*)' to search and $1node$2 to
replace. In the replace dialog simply replace tree
with node and disable the "Match whole string" check
box to achieve the same effect.
-
To search for 'name' or 'names':
'names?'
-
To search for 'tree' or 'node':
'(tree|node)'
-
An arbitrary word consisting of letters and numbers:
[0-9a-zA-Z]+
- ...
