See <a href="http://java.sun.com/javase/6/docs/api/java/lang/Appendable.html">the official Java API doc</a> for details.

abstract class Appendable {

//  Appendable append(char c) throws IOException;
//
//  Appendable append(CharSequence charSquence) throws IOException;
//
//  Appendable append(CharSequence charSquence, int start, int end) throws IOException;

 Appendable append(String text);
}