Re: [ jEdit-users ] OT: Macro-Madness...probably a n00by problem

[<ne...@ho...>]

Since foo/bar/baz seems a little abstract, I thought I'd give a more 
concrete example.


import java.util.*;

public class Widget {

  // for some reason, we want to keep track of all widgets that have 
been created; this is not a good idea or a good way to do this.. it's 
just an example; this is static since we need to keep just one global list
  private static List allWidgets = new LinkedList();

  // this is non-static; each widget instance will have it's own name
  private String name;


  public Widget(String name) {
    this.name = name;
    allWidgets.add(this);
  }


  public String getName() {
    // this won't compile because name is not static
    //return Widget.name;

    // this will work
    //return this.name;

    return name;
  }


  public static int getCount() {
    // this won't compile; no 'this' in a static method
    //return this.allWidgets.size();

    // this will work
    //return Widget.allWidgets.size();

    return allWidgets.size();
  }


  public static Iterator getAllWidgets() {
    return allWidgets.iterator();
  }


  public static void main(String[] args) {
    // by convention, your reference (instance) names should be in 
lower-case so you can distinguish them from class names, which should be 
in upper-case
    Widget a = new Widget("Car");
    Widget b = new Widget("Banana");

    // this is the preferred way to refer to a static member (through 
it's class name)
    System.out.println("There are " + Widget.getCount() + " widgets.");

    // this is legal but may cause confusion; the count doesn't belong 
to a, but to the entire class
    System.out.println("There are " + a.getCount() + " widgets.");

    // it's clear that the name belongs to a single widget
    System.out.println("Widget a is named: " + a.getName());

    // this will not compile since getName() is not static; without a 
widget instance, you have no name, you have no name
    System.out.println("Widget a is named: " + Widget.getName());
  }


}