// Matcher to find an image tag. The 'html' variable contains the <ACRONYM>HTML</ACRONYM> in question
Matcher mImg  = Pattern.compile("(?id)<IMG\\s+(.*?)/?>").matcher(html);
// Matcher to find an ALT attribute (to be applied to an IMG tag's body within the same 'html' variable)
Matcher mAlt  = Pattern.compile("(?ix)\\b ALT \\s* =").matcher(html);

// Matcher to find a newline
Matcher mLine = Pattern.compile("\\n").matcher(html);

// For each image tag within the html . . . 
while (mImg.find())
{

   // Restrict the next <ACRONYM>ALT</ACRONYM> search to the body of the just-found image tag
   mAlt.region( mImg.start(1), mImg.end(1) );
   // Report an error if no <ACRONYM>ALT</ACRONYM> found, showing the whole image tag found above
   if (! mAlt.find()) {

      // Restrict counting of newlines to the text before the start of the image tag
      mLine.region(0, mImg.start());

      int lineNum = 1; // The first line is numbered 1
      while (mLine.find())
              lineNum++; // Each newline bumps up the line number

      System.out.println("Missing ALT attribute on line " + lineNum);
   }

}




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Copyright 1997-2024 Jeffrey Friedl