Question

I’ve been struggling with doing some relatively straightforward regular expression matching in Java 1.4.2. I’m much more comfortable with the Perl way of doing things. Here’s what’s going on:

I am attempting to match /^<foo>/ from ‘<foo><bar>’

I try:

Pattern myPattern= Pattern.compile('^<foo>'); Matcher myMatcher= myPattern.matcher('<foo><bar>'); System.out.println(myMatcher.matches()); 

And I get ‘false’

I am used to saying:

print '<foo><bar>' =~ /^<foo>/; 

which does indeed return true.

After much searching and experimentation, I discovered this which said:

‘The String method further optimizes its search criteria by placing an invisible ^ before the pattern and a $ after it.’

When I tried:

Pattern myPattern= Pattern.compile('^<foo>.*'); Matcher myMatcher= myPattern.matcher('<foo><bar>'); System.out.println(myMatcher.matches()); 

then it returns the expected true. I do not want that pattern though. The terminating .* should not be necessary.

Then I discovered the Matcher.useAnchoringBounds(boolean) method. I thought that expressly telling it to not use the anchoring bounds would work. It did not. I tried issuing a

myMatcher.reset(); 

in case I needed to flush it after turning the attribute off. No luck. Subsequently calling .matches() still returns false.

What have I overlooked?

Edit: Well, that was easy, thanks.

Answer 1

Use the Matcher find method (instead of the matches method)