title: RowFilter.regexFilter multiple columns
body: <p>I am currently using the following to filter my <code>JTable</code></p>
  
  <pre><code>RowFilter.regexFilter( 
           Pattern.compile(textField.getText(), 
           Pattern.CASE_INSENSITIVE).toString(),     columns );
  </code></pre>
  
  <p>How do I format my <code>textField</code> or filter so if I want to filter multiple columns I can do that. Right now I can filter multiple columns but my filter can only be of one of the columns</p>
  
  <p>An example might help my explanation better: </p>
  
  <pre><code>Name Grade GPA
  Zac   A    4.0
  Zac   F    1.0
  Mike  A    4.0
  Dan   C    2.0
  </code></pre>
  
  <p>The text field would contain <code>Zac A</code> or something similar and it would show the first Zac row if <code>columns</code> was <code>int[]{0, 1}</code>. Right now if I do the above I get nothing. The filter <code>Zac</code> works but I get both <code>Zac</code>'s. <code>A</code> also works but I would then get <code>Zac A 4.0</code> and <code>Mike A 3.0</code>. </p>
  
  <p>I hope I have explained my problem well. Please let me know if you do not understand.</p>