[antlr-interest] simple URL extractor

[bace.spam at gmx.net]

Hi all,

I want to extract an URL from a text with antlr v3. To separate the URL from the remaining, I want to search for each occurrence of 'http://'.

So I defined the lexer rule:
HTTP_INDICATOR : 'http://';

and parser rule:
url : HTTP_INDICATOR host (port)? (SLASH path)*;


If I uses this definition, and input something like
'text http://www.goolge.com/index.html further text'
then the parser doesn't work as I imagined. The error message is that 't' was expected instead of 'm'. (The parser wants to match the 'html' with 'http://') But why?

Has anyone an idea how I can tell the lexer to search for the 'http://'?

And as I tried to put the 'http://' in this parser rule (instead of the HTTP_INDICATOR) I get an exception. Is it true that I cannot use literals in parser rules (I got every time an exception)? But in the examples for antlr v3 are literals in parser rules used?!

Best,
Markus
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