Java Sound API - capturing microphone

I have been reading up on the Sound API for Java for a couple of days I am unable to make sense of it. I am decent programmer, I just having difficulty getting my head around the API.

I have been trying to capture audio from my microphone and display a wave graph in real time.

I am having trouble capturing audio, they say in the tutorial to do this, but I cant seem to get it to work.

Any suggestions and help would be much appreciated, a line by line answer would be ideal.

Please and thank you.

import javax.sound.sampled.AudioFormat;
import javax.sound.sampled.AudioSystem;
import javax.sound.sampled.DataLine;
import javax.sound.sampled.LineUnavailableException;
import javax.sound.sampled.TargetDataLine;

public class FindLine {

 public static void main (String[] args){

  AudioFormat format = new AudioFormat(22000,16,2,true,true);
  TargetDataLine line;
  DataLine.Info info = new DataLine.Info(TargetDataLine.class, 
      format); // format is an AudioFormat object
  if (!AudioSystem.isLineSupported(info)) {
      // Handle the error ... 
  }
  // Obtain and open the line.
  try {
      line = (TargetDataLine) AudioSystem.getLine(info);
      line.open(format);
  } catch (LineUnavailableException ex) {
      // Handle the error ... 
  }
 }

}