In this article, we shall be animating the applet window with a 1-second delay. The idea is to display the system time of every instance.
Approach:
Here 6 seven-segment displays are created using the Java Applet library to print the system time in HH:MM:SS format. Each segment of the seven-segment display, numbered as follows can be lit in different combinations to represent the numbers 0-9.
We have 6 seven-segment display for displaying the time in HH:MM:SS pattern. Each segment numbered as the following can be lit in different combinations to represent the numbers 0-9.
We can assume every single segment as 1 bit so (0-9) 10 number can make 10 different combinations.
e.g. if we want to display 0 we should lit-up the segments 0, 1, 2, 3, 4, 5. So this combination will make the number (2^0 | 2^1 | 2^2 | 2^3 | 2^4 | 2^5) = 63.
Below is the implementation of the above approach:
Java
// Java program to illustrate// digital clock using Applets import java.applet.Applet;import java.awt.*;import java.util.*; public class digitalClock extends Applet { @Override public void init() { // Applet window size this.setSize(new Dimension(800, 400)); setBackground(Color.white); new Thread() { @Override public void run() { while (true) { repaint(); delayAnimation(); } } }.start(); } // Animating the applet private void delayAnimation() { try { // Animation delay is 1000 milliseconds Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } } // Function that receive segment combination value // for each digit, position of the display public void display(int val, int pos, Graphics g) { // lit-up the i-th segment // 0-th segment if ((val & 1) != 0) g.fillRect(pos, 150, 5, 50); // 1-st segment if ((val & 2) != 0) g.fillRect(pos, 145, 50, 5); // 2-nd segment if ((val & 4) != 0) g.fillRect(pos + 45, 150, 5, 50); // 3-rd segment if ((val & 8) != 0) g.fillRect(pos + 45, 200, 5, 50); // 4-th segment if ((val & 16) != 0) g.fillRect(pos, 250, 50, 5); // 5-th segment if ((val & 32) != 0) g.fillRect(pos, 200, 5, 50); // 6-th segment if ((val & 64) != 0) g.fillRect(pos + 5, 200, 40, 5); } // Paint the applet @Override public void paint(Graphics g) { // Combination values of different digits int[] digits = new int[] { 63, 12, 118, 94, 77, 91, 123, 14, 127, 95 }; // Get the system time Calendar time = Calendar.getInstance(); int hour = time.get(Calendar.HOUR_OF_DAY); int minute = time.get(Calendar.MINUTE); int second = time.get(Calendar.SECOND); // Deciding AM/PM int am = 1; if (hour > 12) { hour -= 12; am = 0; } // Display hour // tens digit display(digits[hour / 10], 150, g); // units digit display(digits[hour % 10], 225, g); // Display minute // tens digit display(digits[minute / 10], 325, g); // units digit display(digits[minute % 10], 400, g); // Display second // tens digit display(digits[second / 10], 500, g); // units digit display(digits[second % 10], 575, g); // Display AM/PM if (am == 1) g.drawString("am", 650, 250); else g.drawString("pm", 650, 250); // Display ratio signs g.fillRect(300, 175, 5, 5); g.fillRect(300, 225, 5, 5); g.fillRect(475, 175, 5, 5); g.fillRect(475, 225, 5, 5); }} |
Output:
