Using Blue J

[eminem_ayeesha]

hi everyone, i am a uni student who's just started java programming. at the moment we programme with the interface called BlueJ, i am not sure how many use this or have heard of it but i am having problems, i have got a list of excercises i have done some but i just cant... somebody help please

[ArchAngel]

What's the problem?

[eminem_ayeesha]

well i got this exercise to change a piece of code to make it do something else, and to also make that change a method, java is totally new to me so i am stuck

[eminem_ayeesha]

its meant to be really easy, but i am new at this and unfortunately its not sticking this is the code

public class Picture
{
    private Square wall;
    private Square window;
    private Triangle roof;
    private Circle sun;

public Picture()
    {

 public void draw()
    {
        wall = new Square();
        wall.moveVertical(80);
        wall.changeSize(100);
        wall.makeVisible();
        
        window = new Square();
        window.changeColor("black");
        window.moveHorizontal(20);
        window.moveVertical(100);
        window.makeVisible();

        roof = new Triangle();  
        roof.changeSize(50, 140);
        roof.moveHorizontal(60);
        roof.moveVertical(70);
        roof.makeVisible();

        sun = new Circle();
        sun.changeColor("blue");
        sun.moveHorizontal(180);
        sun.moveVertical(-10);
        sun.changeSize(60);
        sun.makeVisible();
        
      
    }public void setBlackAndWhite()
    {
        if(wall != null)   
{
            wall.changeColor("black");
            window.changeColor("white");
            roof.changeColor("black");
            sun.changeColor("black");
            
        }
    }
{
        if(wall != null) 
 {
            wall.changeColor("red");
            window.changeColor("black");
            roof.changeColor("green");
            sun.changeColor("yellow");
            
        }
    }

}

as you can see all that does is display a picture in the blue j interface, i was meant to change the image so as the sun acts like a sunset, using the slowMoveVertical method, but i have tried to do it and still cant and when i achieve that i am meant to make it a method, its all confusing to me

[ArchAngel added CODE tags]

[ArchAngel]

This code isn't that helpful as there are several classes whos definition we don't know: Square, Circle, Triangle etc. Please give definitions of these classes.

Also, where is the BlueJ picture loaded?