How to extract substring in Groovy?

Question

I have a Groovy method that currently works but is real ugly/hacky looking:

def parseId(String str) {
    System.out.println("str: " + str)
    int index = href.indexOf("repositoryId")
    System.out.println("index: " + index)
    int repoIndex = index + 13
    System.out.println("repoIndex" + repoIndex)
    String repoId = href.substring(repoIndex)
    System.out.println("repoId is: " + repoId)
}

When this runs, you might get output like:

str: wsodk3oke30d30kdl4kof94j93jr94f3kd03k043k?planKey=si23j383&repositoryId=31850514
index: 59
repoIndex: 72
repoId is: 31850514

As you can see, I'm simply interested in obtaining the repositoryId value (everything after the = operator) out of the String. Is there a more efficient/Groovier way of doing this or this the only way?

Answer 1

There are a lot of ways to achieve what you want. I'll suggest a simple one using split:

sub = { it.split("repositoryId=")[1] }

str='wsodk3oke30d30kdl4kof94j93jr94f3kd03k043k?planKey=si23j383&repositoryId=31850514'

assert sub(str) == '31850514'

Answer 2

or a shortcut regexp - if you are looking only for single match:

String repoId = str.replaceFirst( /.*&repositoryId=(\w+).*/, '$1' )