Question

I’ve been trying to solve this issue for some time but still didn’t find the answer. The aim is to get some data from a HTML webpage. I can do all the internet related part but i’ve got a problem. This is the string i have:

class=”datastream-graph-value”>
496

The problem are those quotation marks because otherwise my app would be able to get the “496” which is the important data, but with them there i can’t get my data.

Which would be a good way to get that data? (Note that after the “>” symbol there is a “\n”)

Thank you mates!

Answer 1

While I don’t normally recommend regular expressions to read xml but HTML with an XML parser can be nightmare.

With the below sample.

<a class="datastream-graph-value" href="http=blah" > 496</a>
<a class="other"> 496</a>

Use the below regular expression it should handle it well.

(class=["][^>"]*["])

Gives a great example of how to use that regex.
http://www.vogella.com/articles/JavaRegularExpressions/article.html

If you need a code sample reply back and we will see what we can’t work out.

edit:

I was bored so I thought why not put a sample together

package temp;


import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class RegexTestPatternMatcher {
  public static final String EXAMPLE_TEST = "<a class=\"datastream-graph-value\" href=\"http=blah\" > 496</a> <a class=\"other\"> 496</a>";

  public static void main(String[] args) {
    Pattern pattern = Pattern.compile("(class=[\"][^>\"]*[\"])");
    // In case you would like to ignore case sensitivity you could use this
    // statement
    // Pattern pattern = Pattern.compile("\\s+", Pattern.CASE_INSENSITIVE);
    Matcher matcher = pattern.matcher(EXAMPLE_TEST);
    // Check all occurance
    while (matcher.find()) {
      System.out.print("Start index: " + matcher.start());
      System.out.print(" End index: " + matcher.end() + " ");
      String match = matcher.group();
      match = match.replace("class=", "");
      System.out.println(match);
    }
    // Now create a new pattern and matcher to replace whitespace with tabs
    Pattern replace = Pattern.compile("\\s+");
    Matcher matcher2 = replace.matcher(EXAMPLE_TEST);
    System.out.println(matcher2.replaceAll("\t"));
  }
}