Add second year

second/semester2/CT255/Assignments/Assigment-05/Alien.java

@@ -0,0 +1,55 @@
+import java.awt.*;
+import javax.swing.*;
+
+public class Alien extends Sprite2D {
+    public static long framesDrawn = 0;    // variable to hold the number of frames drawn
+    public static int aliensKilled = 0;     // static variable to hold the count of the aliens killed - in alien class as it's intended to be modified by aliens
+    public static int stepSize = 0;         // how far the aliens move each frame - 0 by default but will get increased to 5 immediately
+    private Image altImage;
+
+    public Alien(Image image, Image altImage) {
+        super(image);
+        this.altImage = altImage;
+    }
+
+    // method to randomly move the alien
+    public void move(boolean right) {
+        // changing the x & y co-ordinates (inherited from superclass) by either plus or minus the stepSize, depending on the direction
+        if (right) {
+            x += stepSize;
+        }
+        else {
+            x -= stepSize;
+        }
+    } 
+
+    // method to move aliend down 
+    public void moveDown() {
+        y += 25;
+    }
+
+    // overridden paint method to allow animation
+    @Override 
+    public void paint(Graphics g) {
+        framesDrawn++;
+        
+        if (framesDrawn % 100 < 50) {
+            g.drawImage(image, x, y, null);
+        }
+        else {
+            g.drawImage(altImage, x, y, null);
+        }
+    }
+
+    @Override 
+    // overridden kill method to set isAlive to false and increment the aliensKilled counter
+    public void kill() {
+        isAlive = false;
+        aliensKilled++;
+    }
+
+    // method to increase the stepsize of the aliens
+    public static void speedUp() {
+        stepSize = stepSize + 3;
+    } 
+}