mydocument.java

一个贪吃蛇游戏

/**
 * @(#)MyDocument.java
 * @A document used to limiting the length of the input text.
 *
 * @Link Scholes
 * @version 1.00 2008/7/21
 */

package GUI;

//Java extension packages
import javax.swing.text.*;

public class MyDocument extends PlainDocument
{
	private int length;
	
	//construct a document with specified length limit of the input text
	public MyDocument(int n)
	{
		super();
		length = n;
	}
	
	//limit the input
	public void insertString(int offs,String str,AttributeSet a) throws BadLocationException
	{
		if(getLength() + str.length() < length + 1)
		{
			super.insertString(offs,str,a);
		}
	}
}	//end class MyDocument