주민번호체크(Java Swing로 구현)

import javax.swing.*;
import javax.swing.text.*;
import java.awt.*;
import javax.swing.border.*;
import java.awt.event.*;
import javax.swing.event.*;

public class Jumin extends JPanel implements ActionListener,KeyListener
{
 JPanel top,middle,bottom;
 JPanel top_top,top_down;
 JLabel jumin_title,jumin_result_title;
 JTextField jumin_result;
 JTextField jumin_left,jumin_right;
 JButton reset;
 static int changeLength;

 public Jumin(){
  setLayout(new GridLayout(2,1));

  top=new JPanel();
  setBackground(new Color(204,204,204));
  top.setBorder(new TitledBorder(new EtchedBorder(),"(주)BIT DataSystems Corp.",TitledBorder.LEFT,TitledBorder.TOP,MyFont.sans()));
  setLayout(new FlowLayout());

  top_top=new JPanel();
  
  jumin_title=new JLabel("쭌 민증번호를 입력해줘..");
  jumin_title.setFont(new Font("Serif",Font.LAYOUT_LEFT_TO_RIGHT,12));
  top_top.add(jumin_title);
  top.add(top_top);

  top_down=new JPanel();
  setLayout(new FlowLayout());
  jumin_left=new JTextField();
  jumin_left.setColumns(6);
  jumin_left.setBackground(new Color(221,221,221));
  jumin_left.setForeground(new Color(57,86,147));
  jumin_left.addActionListener(this);          //...
  jumin_left.getDocument().addDocumentListener(new MyDocumentListener());  //...
  top_down.add(jumin_left);

  jumin_right=new JTextField(7);
  jumin_right.setBackground(new Color(221,221,221));
  jumin_right.setForeground(new Color(57,86,147));
  jumin_right.addActionListener(this);
  top_down.add(jumin_right);
  top.add(top_down);

  add(top);

  
  middle=new JPanel();
  middle.setBorder(new TitledBorder(new EtchedBorder(),"조회 결과",TitledBorder.LEFT,TitledBorder.TOP,MyFont.sans()));
  setLayout(new FlowLayout());

  jumin_result_title=new JLabel("간첩일까 아닐까..");
  jumin_result_title.setFont(new Font("Serif",Font.LAYOUT_LEFT_TO_RIGHT,12));

  jumin_result=new JTextField(11);
  jumin_result.setEditable(false);  //입력못하게
  jumin_result.setBackground(new Color(221,221,221));
  jumin_result.setForeground(new Color(57,86,147));

  reset=new JButton("새로고침");
  reset.setFont(new Font("Serif",Font.LAYOUT_LEFT_TO_RIGHT,12));
  reset.addActionListener(this);
  reset.addKeyListener(this);

  middle.add(jumin_result_title);
  middle.add(jumin_result);
  middle.add(reset);

  add(middle);

  jumin_left.requestFocus();         

 }

  public void keyPressed(KeyEvent e){ //======================
   if(e.getSource() == reset){
    jumin_left.setText("");
             jumin_right.setText("");
             jumin_result.setText("");
             jumin_left.requestFocus();
    }
    }
   
 public void keyTyped(KeyEvent e){}
 public void keyReleased(KeyEvent e){}
 
 class MyDocumentListener implements DocumentListener {
  public void insertUpdate(DocumentEvent e) {
   updateLog(e, "inserted into");
   }
  public void removeUpdate(DocumentEvent e) {
   updateLog(e, "removed from");
   }
  public void changedUpdate(DocumentEvent e) { }
  public void updateLog(DocumentEvent e, String action) {
   Document doc = (Document)e.getDocument();
   changeLength = doc.getLength();
   abc(changeLength);
  }
  public void abc(int i){
   i++;
   if(i == 7) jumin_right.requestFocus();
   }
  }
  
  public void actionPerformed(ActionEvent ae){

   if(ae.getSource()==reset){
    jumin_left.setText("");
    jumin_right.setText("");
    jumin_result.setText("");
    jumin_left.requestFocus();
   }
   else if(ae.getSource() == jumin_left){
    jumin_result.setText("");
    jumin_right.requestFocus();
   }
   else if(ae.getSource() == jumin_right){
                String str1 = jumin_left.getText().trim();
                String str2 = jumin_right.getText().trim();
    

    if(CheckID.check(str1,str2)){
     jumin_result.setText("");
                    jumin_result.setText("간첩아이네.."+"\n");
                    jumin_result.requestFocus();
    }
    else {
                jumin_result.setText("");
                jumin_result.setText("우쒸.. 너 간첩이지.."+"\n");
                jumin_result.requestFocus();   
                }  
   }
  }

    public static void main(String[] args) {
    JFrame.setDefaultLookAndFeelDecorated(true);
    JFrame frame = new JFrame("주민검사");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setContentPane(new Jumin());
    frame.setSize(390,190);
 frame.setLocation(300,150);
    frame.setVisible(true);
  }
}

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class CheckID {
   public static boolean check(String str1, String str2){
    
    String str_sum=str1+str2;
    if(str_sum.length()>13){
     return false;
    }
    String index="2345678923456";

    char[] arry = str_sum.toCharArray();
    int last= Integer.parseInt(String.valueOf(arry[12]));

    int sum=0;
    int [] juminNo = new int[13];
    int [] juminNoo=new int[13];
    int magicky,magicky1;

    for(int i=0;i<12;i++){
     
     juminNo[i]=str_sum.charAt(i)-`0`;
           juminNoo[i]=index.charAt(i)-`0`;
           sum+=juminNo[i]*juminNoo[i];
    }
    
    magicky=sum%11;
    magicky1=11-magicky;
    
    if(last==magicky1){
     return true;
    }
    else{
     return false;
    }
    
   }
}

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import java.awt.*;

public class MyFont{ 
 public static Font sans(){
  Font sans = new Font("Sans Serif", Font.LAYOUT_LEFT_TO_RIGHT, 12);
  return sans;
 }
}