passwordrestrict.java

课程设计：ATM Project源码

import javax.swing.*;
import javax.swing.text.*;
import java.awt.Toolkit;

public class PasswordRestrict extends PlainDocument{
	private int maxLength;
	int result;
	JButton btConfirm;
	public PasswordRestrict(int maxLength,JButton button){
		this.maxLength = maxLength;
		this.btConfirm=button;
	}
	public void insertString(int offset,String str,AttributeSet att) throws BadLocationException
	{
		for(int i=0;i<=9;i++){
			result = Integer.toString(i).compareTo(str);
			if (result == 0){ //是数字才处理
            
			  if ( getLength() + str.length() > maxLength ){
		   		Toolkit.getDefaultToolkit().beep();
			  }else{
				super.insertString(offset,str,att);
			  }	
			}
		}
	}
}