Databases
StackOverflow2013
Postsdbo
POgroup counting issue with regex
 

Note that there are some explanatory texts on larger screens.

plurals
  1. POgroup counting issue with regex
    primarykey
    data
    text
    <p><B>EDIT: The RE in the original code is irrelevant (or that it makes any sense). Let's say you're matching <code>(X)|(Y)</code>: two patterns that are combined in the RE with an OR. How to know which pattern was actually matched??</b></p> <p>I'm trying to extract just the text that's mattching the RE <em>within</em> the brackets.</p> <p>The problem i'm facing is that i cannot figure out which <em>actual</em> group was matched, since the group index is <em>not</em> constant because of the OR.</p> <p>Ie in the line marked XXX <code>m.group()</code> returns the entire pattern</p> <pre><code>pat1 abcdef2 </code></pre> <p>And <code>m.group(1)</code> produces</p> <pre><code>pat null </code></pre> <p>And <code>m.group(2)</code> produces</p> <pre><code>null de </code></pre> <p>And <code>m.groupCount()</code> is just a total number of groups in the RE, so it is useless for indexing.</p> <p>What I want the loop to print is</p> <pre><code>pat de </code></pre> <p>It's a shame java doesnt have the perl's m/ operator that'll extract the stuff and put it nicely into an array ;-) </p> <pre><code>import java.io.IOException; import java.util.regex.Matcher; import java.util.regex.Pattern; public class Test { public static void main(String[] args) throws IOException { Pattern p = Pattern.compile("([pat]+)1|abc([de]+)f2"); String original = " pat1 abcdef2555"; Matcher m = p.matcher(original); boolean result = m.find(); while (result) { System.out.println(m.group()); // XXX want to print only matched GROUP!! result = m.find(); } } } </code></pre>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USSaideira
    1. USSaideira
    plurals
    1. This table or related slice is empty.
    1. PL
      singulars
      1. LTLinked
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. POgroup counting issue with regex
      1. This table or related slice is empty.
      1. VTDownMod
    2. VO
      singulars
      1. POgroup counting issue with regex
      1. This table or related slice is empty.
      1. VTDownMod
    3. VO
      singulars
      1. POgroup counting issue with regex
      1. This table or related slice is empty.
      1. VTUpMod
    1. COI'm not sure I understand. Is it possible that you want your regex to be "(pat)1|pat(ter)n2"? The way you have it, I believe, would return any variation of the letters P A and T. I.e. [pat]+ would match "ppppt", "atpaptpap", and so on. Maybe I'm wrong on this. I'm kind of new to regex.
      singulars
      1. POgroup counting issue with regex
      1. USbozdoz
    2. COIf your strings were `jjjpatssjpttattpppt1` and `ksjdhfabcdddddddddf2` what would be your desired output? As your expression is currently, the matches would be successful and the text would be `pttattpppt` and `ddddddddd` respectfully. I ask because like others here, I think you may have a poor understanding of what your expression is specifying and possibly regex syntax in general
      singulars
      1. POgroup counting issue with regex
      1. USCode Jockey
    3. COonly "pat" will be matched for the 2 strings you provided.
      singulars
      1. POgroup counting issue with regex
      1. USSaideira
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload