programtocreateasafewith4digitcodes.java

// program to create a safe with 4 digit codes

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.applet.*;

public class Safe extends JApplet implements ActionListener
{
 private JButton button[];
 private TextField code;
 private Label label;
 private int comb;
 private int number;
 private Panel panel1, panel2;
 private String status;
 private String entered;

 public void init()
 {
  Container cp = getContentPane();
  panel1 = new Panel();
  cp.add(panel1,"North");
  label = new Label("CLOSED");
  panel1.add(label); // add the label to the pane
  label.setAlignment(Label.LEFT);  // set label label to the left

  //text field
  code = new TextField(20);
  //code.setEditable(false);
  panel1.add(code);

  panel2 = new Panel();
  cp.add(panel2,"Center");

  // set grid layout for panel2

  panel2.setLayout(new GridLayout(4,3,5,5));
  button = new JButton[13];

  int i=0;
  for (i=0;i<10;i+=1)
  {
   // array buttons
   button[i] = new JButton(Integer.toString(i));
   panel2.add(button[i]);
   button[i].addActionListener(this);

  }
  button[10] = new JButton("CLOSE");
  button[10] .setForeground(Color.red);
  button[10].addActionListener(this);

  button[11] = new JButton("OPEN");
  button[11] .setForeground(Color.red);
  button[11].addActionListener(this);

  button[12] = new JButton("NEW CODE");
  button[12] .setForeground(Color.red);
  button[12].addActionListener(this);

  // add remaining buttons to the layout

  panel2.add(button[10]);
  panel2.add(button[11]);
  panel2.add(button[12]);

 } // end the naming and positioning of the buttons on the screen

 public void actionPerformed(ActionEvent e)
 {
  // checks if the buttons are pressed
  String a;
  int num1,num2,num3,num4;
  int j;
  int tries = 6;
  int total = 0;
  String passcode = "1234";
  String entered="";
  int n;
  num2 = 1000;
  num3=0;
  if (total<4)
  {
   for (j=0;j<10;j+=1)
   {

    if (e.getSource()==button[10])
    {
     num1=j;
     num3=num1*num2+num3;
     num2=num2/10;
     total+=1;
     a=Integer.toString(num3);
     code.setText(a);
    }

   }
  entered=Integer.toString(num3);
  code.setText(entered);
  }
  else
  {
   label = new Label("LOCKED AND ALARMED");
   panel1.add(label); // add the label to the pane
   tries = 4;
   code.setText(entered);
  }

  if(e.getSource()==button[10])
  {
   label = new Label("CLOSED");
   panel1.add(label); // add the label to the pane
   passcode = passcode;
   total =0;
  }

  if(e.getSource()==button[11])
  {
   if (tries>0)
   {

    if ( entered == passcode )
    {
     label = new Label("OPEN");
     panel1.add(label); // add the label to the pane
     tries = 6;
     total = 0;
    }
    else
    {
     tries = tries - 1;
     code.setText("Incorrect code");
     label = new Label("CLOSED");
     panel1.add(label); // add the label to the pane
     total = 0;
    }
   }
   else
   {
    label = new Label("ALARMED AND LOCKED");
    panel1.add(label); // add the label to the pane
    code.setText("Enter new code");
   }

  }

  if(e.getSource()==button[12]);
  {
   entered="";
   total = 0;
   while (total<4)
   {
   for (j=0;j<10;j+=1)
   {

    if (e.getSource()==button[10])
    {
     num1=j;
     num3=num1*num2+num3;
     num2=num2/10;
     total+=1;
    }

   }
   entered=Integer.toString(num3);
   code.setText(entered);
   }
   passcode = entered;
   tries = 6;
   total = 0;
   label = new Label("CLOSED");
   panel1.add(label); // add the label to the pane
  }
 }//ends action performed
}// ends

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