How to implement a SQL like 'LIKE' operator in java?

java sql regex string wildcard
Chris picture Chris · May 22, 2009 · Viewed 111.3k times · Source

I need a comparator in java which has the same semantics as the sql 'like' operator. For example:

myComparator.like("digital","%ital%");
myComparator.like("digital","%gi?a%");
myComparator.like("digital","digi%");

should evaluate to true, and

myComparator.like("digital","%cam%");
myComparator.like("digital","tal%");

should evaluate to false. Any ideas how to implement such a comparator or does anyone know an implementation with the same semantics? Can this be done using a regular expression?

Answer

Bob picture Bob · May 22, 2009

.* will match any characters in regular expressions

I think the java syntax would be

"digital".matches(".*ital.*");

And for the single character match just use a single dot.

"digital".matches(".*gi.a.*");

And to match an actual dot, escape it as slash dot

\.

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