title: UnsupportedOperationException when trying to add (Arraylist)
body: <p>I'm having a small issue with this program. It's an appointment book, and the idea is to be able to add contacts and events.</p>
  
  <p>Here is the first part of my code and the one I'm having trouble with: </p>
  
  <pre><code>    String aux = " ";
      String aux2 = " ";
      long aux3 = 0;
  
      Arraylist &lt;Person&gt; cole1 = new Arraylist();
  
      do{
      System.out.println("Welcome");
      System.out.println("- Book");
      System.out.println("1. Add contact");
      System.out.println("2. See contacts");
      System.out.println("3. Remove contacts");
  
      switch(Integer.parseInt(teclado.readLine())){
          case 1:
              for(int i = 0; i&lt;cole1.size();i++){
  
                  System.out.println("Write the name");
                  aux = teclado.readLine();
                  System.out.println("Write the email");
                  aux2 = teclado.readLine();
                  System.out.println("Write the phone number");
                  aux3 = Integer.parseInt(teclado.readLine());
  
                  cole1.add(new Person(aux, aux2, aux3));
              }
              break;
  
          default:
              System.out.println("error");
              break;
      }
  
      }while(true);  
  </code></pre>
  
  <p>Here's my person class:</p>
  
  <pre><code>public class Person {
  
  public String getName() {
      return name;
  }
  
  public void setName(String name) {
      this.name = name;
  }
  
  public String getEmail() {
      return email;
  }
  
  public void setEmail(String email) {
      this.email = email;
  }
  
  public float getNum() {
      return num;
  }
  
  public void setNum(long num) {
      this.num = num;
  }
  
  private String name;
  private String email;
  private long num;
  
  public Persona(String n, String e, long nu){
      this.name=n;
      this.email=e;
      this.num=nu;
  
  }
  
  
   }
  </code></pre>
  
  <p>This part should be able to create a new person with the name, phone and email attributes. The problem is when I press 1 in my switch for the add option i get the following error:</p>
  
  <pre><code>    Exception in thread "main" java.lang.UnsupportedOperationException: Not supported yet.
      at agenda.Arraylist.size(Arraylist.java:15)
      at agenda.AgendaTest.main(AgendaTest.java:40)
      C:\Users\melis\AppData\Local\NetBeans\Cache\8.2\executor-snippets\run.xml:53: Java returned: 1
      BUILD FAILED (total time: 2 seconds)
  </code></pre>
  
  <p>I can't figure out if its a logic or syntax problem. I've read a few other questions with people having a similar problem. The difference is, all of them where apparently using the Arrays.asList property, which if i understand correctly, Arrays.asList doesn't support add/remove operations.</p>
  
  <p>Any idea on what is going wrong?</p>
  
  <p>Thanks in advance! And sorry if my English is bad.</p>