Creating A Window In 2D Char Array

I am relatively new to java, and i am trying to create a window inside of a 2d char array, and eventually i will have to draw other shapes in this window. so for example

* * * * * * * * *
* *
* *
* *
* *
* *
* *
* *
* * * * * * * * *

The problem is my window is not drawing correctly too the border, but a couple extra chars on the x columns. Here is code. The dimensions of the window will eventually be passed through scanner in main, if i ever work out how to even draw it.Also, in class we never learnt to use the Graphics class, so im pretty sure we are not supposed to use it.

public class Window
{ //default values
private int xRow;
private int yCol;
private char ch;
public char[][] windowz = new char[30][20]; //30,20 (yx)flat values cuz doesnt work

[code]....