title: Error: NullPointerAccess: The variable " " can only be null at this location
body: <p>I am creating a web service that queries my database and returns a list of the object in the database. I get the error: NullPointerAccess: The variable "varname" can only be null at this location. No matter where I put the variable, I get the same warnings. No matter what I put inside the variable, it returns null. Below is the method that it occurs in:</p>
  
  <pre><code>    public List&lt;Contacts&gt; getUsers()
    {     String test = null;
          String username = "root";
          String password = "ticket";
          String tablename = "users";
          String fieldname = "*";
          String query = "SELECT " + fieldname + " FROM " + "android." + tablename + ";";
  
          Contacts cont = new Contacts();
          List&lt;Contacts&gt; lstc = null;
  
          /* this chnk of code can appear more or less verbatim */
          /* in your database apps (including JSPs) */
          String url = "jdbc:mysql://"my IP address":3306/android";
          try{
          Class.forName("com.mysql.jdbc.Driver").newInstance();
          Connection con = DriverManager.getConnection(url, username, password);
          Statement stmt = con.createStatement();
          ResultSet rs = stmt.executeQuery(query);
  
  
          while (rs.next()){
              if (!(rs.getString("username") == null)){
               cont.setUsername(rs.getString("username"));
              }
              if (!(rs.getString("location") == null)){
               cont.setLocation(rs.getString("location"));
              }
              if (!(rs.getString("updated_at") == null)){
               cont.setUpdated_at(rs.getDate("updated_at"));
              }
              if (!(rs.getString("idUsers") == null)){
               cont.setId(rs.getInt("idUsers"));
              }
          }
  
          rs.close();
          stmt.close();
          con.close();
          }catch(Exception e){
              test = e.toString();
          }
           lstc.add(cont); //THIS IS THE VARIABLE THAT IS GIVING THE WARNINGS
          test = "blahbadslf";
          return lstc;
          }
  </code></pre>
  
  <p>The variable that is getting the warnings is my List lstc variable. When I try to add a  Object to the List I get the errors. Any help would be much appreciated. Here is the Class just in case: </p>
  
  <pre><code>public class Contacts{
  private int id;
  private String username;
  private String location;
  private Date updated_at;
  
  public void setId(int id) {
      this.id = id;
  }
  public int getId() {
      return id;
  }
  public void setUsername(String username) {
      this.username = username;
  }
  public String getUsername() {
      return username;
  }
  public void setLocation(String location) {
      this.location = location;
  }
  public String getLocation() {
      return location;
  }
  public void setUpdated_at(Date updated_at) {
      this.updated_at = updated_at;
  }
  public Date getUpdated_at() {
      return updated_at;
  }
  </code></pre>
  
  <p>}</p>
  
  <p>Thanks!</p>