Removed all imports that aren't covered in the Processing reference. 
  If you use java.awt, java.util, or other classes in your sketch, you
  will need to add an import line to the beginning of your sketch.

  Only the classes that are covered in the reference (HashMap, ArrayList, 
  and some others) are now imported by default. This has been done to improve
  overall cross-platform parity and to avoid users unknowingly adding 
  Java classes, and then the sadness that comes when switching to Android
  or JavaScript modes. 

  The list of imports is now hard-coded (no longer read from preferences.txt)
  and includes the following:
  import java.util.HashMap;
  import java.util.ArrayList;
  import java.io.BufferedReader;
  import java.io.PrintWriter;
  import java.io.InputStream;
  import java.io.OutputStream; 

import java.io.IOException;