Something

public class Foo {  String _a;  Integer _b;  public String a() {     if (_a == null)   _a = retrieveA();     return _a;  }  public Integer b() {      if (_b == null)  _b = retrieveB();     return _b;  }  String retrieveA() { return "asdfasdf";}  Integer retrieveB() { return new Integer(42);}}