What we ‘should’ have done in intro

1. What we ‘should’ have done in intro

2. Now we know about other classes and the main() and stuff • I have shown how we could reorganise a solution to the homework in zz-introduction-done-right • An application class that ‘runs’ the code you previously typed into GWD and pasted into the code pad • It also splits up the code into more manageable methods (call just with name if in same class) e.g star() or circle() • I used Kerry’s code – thanks (see directory)

3. Here is documentation for the Application class

5. With a main program of: public static void main(String args[]) { Application app=new Application(); app.runApp(); } And runApp() starts: public class Application{ private InputGetter reader; public Application() { reader=new InputGetter(); } public void runApp() { reader.getInputFromUser("How many times to loop"); int num=Integer.parseInt(reader.getCurrentValue()); for (int i=0;i<num;i++) { System.out.print("Going round the loop "+(i+1)+" time "); reader.getInputFromUser("what do you want to draw in the loop time "+(i+1)+"?"); String name=reader.getCurrentValue(); if (name.equals("star")) { star(); }Etc etc

6. public void runApp() { reader.getInputFromUser("How many to loop"); int num=Integer.parseInt(reader.getCurrentValue()); for (int i=0;i<num;i++) { System.out.print("Going round "+(i+1)+" time "); String name=reader.getCurrentValue(); if (name.equals("star")) { star(); } else if (name.equals("circle")) { circle(); } else if (name.equals("ltt")) { ltt(); } else { System.out.println("cannot do that!"); } } } public void star() { System.out.println("draws star"); //etc

7. So, we can now write programs • These programs can be run from the command line by typing: java Application • This will run the main, which in turn creates a new Application called app and then runs its runApp() method • Maybe we should have done this from start?? • The book doesn’t do it until chapter 5 or so