TextGraph

[Ant_Magma]

I had my Java term paper yesterday, it was terrible. After the exam, i've attempted the question again but i still can't get the correct output. So i would appreciate if you guys can help me out here...

The question:

Create a class, TextGraph, which will draw a diagonal graph using text graphics. Here is an example of what the output of this program would look like if we told it the size was 80x24:

                                                                                                   000
                                                                                            0000
                                                                                       000
                                                                                 000
                                                                          0000
                                                                     000
                                                              0000
                                                          000
                                                   0000
                                             0000
                                       0000
                                 0000

The formula of the graph is, x(height/width)=y

Since the origin starts at the bottom left hand corner, at that position, the first four "0"s are calculated by subsituting x=0,1,2 or 3 into the equation which will give the value y=0 when you convert it to integer

The last three "0"s (upper right hand) is computed based on the value of x=77,78 or 79. All produce y=23

This is the tester class

class TextGraphTester{
	public static void main(String[] args){
		int width=80, height=24;

		if(args.length>=1)width=Integer.parseInt(args[0]);
		if(args.length>=2)height=Integer.parseInt(args[1]);

		TextGraph g=new TextGraph(width, height);
		System.out.print(g);

		TextGraph h=new TextGraph(width, height);
		System.out.print("Equals or not? " +h.equals(g));
		h=new TextGraph(width, height*2);
		System.out.println("Again? " +g.equals(h));
	}
}

End of question...

The following is my version of the code. The methods i used in my code are compulsary with the question.

public class TextGraph{
	private char[][] screen;
	private char zero;	//Automatically initialized as zero
	private int scrW;
	private int scrH;
	private int x;		//for width
	private int y;		//for height

	public TextGraph(int width, int height){
		scrW=width;
		scrH=height;
		screen= new char[scrW][scrH];	//Array is an object. Has to create with 'new'
		setPixel(x,y,zero);
	}

	public TextGraph(){
		scrW=80;
		scrH=40;
		screen= new char[scrW][scrH];	//Empty constructor initializing to default values
	}
	//-------------------------------------------------------------------------------------------
	public int getWidth(){
		return scrW;
	}

	public int getHeight(){
		return scrH;
	}

	public boolean setPixel(int x,int y, char c){
		if((x>scrW)&&(y>scrH)&&(c!='0'))
			return false;
		else
			screen[x][y]=c;

		return false;
	}

	public char getPixel(int x,int y){
		return screen[x][y];
	}

	public void calculate(){
		for(int i=0;i<scrW;i++){
			this.y=i*(scrH/scrW);	//i=x;
			setPixel(i,y,zero);
		}
	}

	StringBuffer sb=new StringBuffer();      //Provided by sjalle, many thx!!
	public String toString(){
		sb.setLength(0);
		for (int i=0; i<screen.length; i++) {
			for (int j=0; j<screen[i].length; j++) {
				sb.append(screen[i][j]);
			}
		}
		return sb.toString();
	}

	public boolean equals(Object o){
		if(o==null)
			return false;
		else if(o.getClass()!=this.getClass())
			return false;
		else{
			TextGraph other=(TextGraph) o;
			if((other.getWidth()==this.getWidth())&&(other.getHeight()==this.getHeight()))
				return true;
		}
		return false;


	}
}

I know this is quite a lengthy thread. For guys out there willing to help, many thanks in advance!!

[ractoc]

first of all, the char zero is automatically initialized as 0. this is not the same as '0'