title: create a directed graph
body: <p>i want create a directed graph , i have three variables : String x,y,z
  and the first vertex contain the 3 variables and the next contain the next 3 until the end of the loop</p>
  
  <p>i have this:</p>
  
  <pre><code>BufferedReader reader = new BufferedReader(
      new StringReader(contentTextArea.getText()));
  
  try {
    str =reader.readLine();
  
    while(str != null) {
      String splitted[] = str.split("\\|");
      String x = splitted[0].trim();
      String y = splitted[1].trim();
      String z = splitted[2].trim();
    }          
  }
  </code></pre>
  
  <p>so this code give me each time 3 strings and i want for each time to create a vertex and an edge and this will create a graph at the end.
  the code could be like this, but i don't know what to write inside 
  <code>createVertex (String x,y,z)</code>,<code>addEdge ()</code> methods.</p>
  
  <pre><code>public class graph {  
    createVertex (String x,y,z);
    addEdge ();
  }
  </code></pre>