Sign Up to our social questions and Answers Engine to ask questions, answer people’s questions, and connect with other people.
Login to our social questions & Answers Engine to ask questions answer people’s questions & connect with other people.
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Please briefly explain why you feel this question should be reported.
Please briefly explain why you feel this answer should be reported.
Please briefly explain why you feel this user should be reported.
I am writing a Java utility that helps me to generate loads of data for performance testing. It would be really cool to be able to specify a regex for Strings so that my generator spits out things that match this.
Is something out there already baked that I can use to do this? Or is there a library that gets me most of the way there?
Firstly, with a complex enough regexp, I believe this can be impossible. But you should be able to put something together for simple regexps.
If you take a look at the source code of the class java.util.regex.Pattern, you’ll see that it uses an internal representation of Node instances. Each of the different pattern components have their own implementation of a Node subclass. These Nodes are organised into a tree.
By producing a visitor that traverses this tree, you should be able to call an overloaded generator method or some kind of Builder that cobbles something together.