Question

Possible Duplicate:
RegEx match open tags except XHTML self-contained tags

I have a file containing about 2000 lines such as this:

<nobr>&nbsp;&nbsp;&nbsp;&nbsp;<a href="../Carbon_Monoxide_Poisoning_Prevention.htm"><b>poisoning - prevention</b></a></nobr><br>
<nobr>&nbsp;&nbsp;&nbsp;&nbsp;<a href="../Carbon_Monoxide_Symptoms.htm"><b>symptoms</b></a></nobr><br>

1.) the URL is ALWAYS in the form of ../foo.html

2.) the display name is SOMETIMES enclosed with <b> ... </b> tags, and sometimes not.

3.) each line in the file contains up to four   that I need to count and flag as spaces. These will EVENTUALLY be used to format indents, so I need to capture the information somehow.

I need to have the hyperlink, display name and number of spaces name in a delimited flat file as follows (based on the above data):

../Carbon_Monoxide_Poisoning_Prevention.htm,poisoning - prevention,4
../Carbon_Monoxide_Symptoms.htm,symptoms,4

. While I can parse this through a whole mess of String, substring, and if statements, that seems to be more cumbersome than it needs to be. I was investigating Regex (my first time doing so), but am a little unclear on some of the syntax; I learn best seeing a code sample similar to my applications, but have not been able to find examples of anything that quite fits.

Any help would be appreciated!

Answer 1

You can only grab one thing at a time, all the URLs at once, display name, or the spaces. I would not use regular expressions per say to do this, but here is how I would go about it if I absolutely had to use regex:

To grab the url in a line: \.\./.*\.html?

To grab the display name: (?<=("|b)>)[a-ZA-Z].+?(?=(</(a|b)))

To grab the spaces (simply):  

---

I would first split the file by the <br> tag to get the individual lines. And the run the regex above to pull out the url, display name, and spaces and combine them in a delimited output. I’m sure Java has a preg_match_all equivalent to match all patterns found (would be useful for the spaces & counting them)

Note that these patterns were tested in Sublime Text and probably will not work in Java without a little tweaking. I can modify my answer later to include the Java if needed, but for a one-off thing like this you may be better off using Python or some other scripting language.

Best of luck!