added lab11 ex1

src/lab11_flyweight/ex1/Brush.java

@@ -0,0 +1,16 @@
+package lab11_flyweight.ex1;
+
+public class Brush implements DrawingTool {
+    private final Props props;
+
+    public Brush(Props props) {
+        this.props = props;
+    }
+
+    @Override
+    public void draw(String text) {
+        System.out.println("Drawing '" + text + "' in " + props.size + ", color:" + props.color);
+    }
+
+    public record Props(Size size, Color color) {}
+}

src/lab11_flyweight/ex1/BrushFactory.java

@@ -0,0 +1,17 @@
+package lab11_flyweight.ex1;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class BrushFactory {
+    private final Map<Brush.Props, Brush> brushes = new HashMap<>();
+
+    public Brush getBrush(Brush.Props props) {
+        Brush brush = brushes.get(props);
+        if (brush == null) {
+            brush = new Brush(props);
+            brushes.put(props, brush);
+        }
+        return brush;
+    }
+}

src/lab11_flyweight/ex1/Color.java

@@ -0,0 +1,6 @@
+package lab11_flyweight.ex1;
+
+public enum Color {
+    BLUE,
+    RED
+}

src/lab11_flyweight/ex1/DrawingTool.java

@@ -0,0 +1,5 @@
+package lab11_flyweight.ex1;
+
+public interface DrawingTool {
+    void draw(String text);
+}

src/lab11_flyweight/ex1/Main.java

@@ -0,0 +1,31 @@
+package lab11_flyweight.ex1;
+
+public class Main {
+    public static void main(String[] args) {
+        BrushFactory factory = new BrushFactory();
+        Brush.Props props1 = new Brush.Props(Size.THICK, Color.RED);
+        Brush.Props props2 = new Brush.Props(Size.THIN, Color.BLUE);
+        DrawingTool brush1 = factory.getBrush(props1);
+        DrawingTool brush2 = factory.getBrush(props1);
+
+        brush1.draw("I am drawing with my first thick red brush");
+        brush2.draw("I am drawing with my second thick red brush");
+        System.out.println("first thick red brush hashcode: " + brush1.hashCode());
+        System.out.println("second thick red brush hashcode: " + brush2.hashCode());
+
+        System.out.println();
+        DrawingTool pencil = new Pencil();
+        pencil.draw("Bonjour");
+        System.out.println();
+
+        DrawingTool brush3 = factory.getBrush(props2);
+        DrawingTool brush4 = factory.getBrush(props2);
+
+        brush3.draw("I am drawing with my first thin blue brush");
+        brush4.draw("I am drawing with my second thin blue brush");
+        System.out.println("first thin blue brush hashcode: " + brush3.hashCode());
+        System.out.println("second thin blue brush hashcode: " + brush4.hashCode());
+
+
+    }
+}

src/lab11_flyweight/ex1/Pencil.java

@@ -0,0 +1,8 @@
+package lab11_flyweight.ex1;
+
+public class Pencil implements DrawingTool {
+    @Override
+    public void draw(String text) {
+        System.out.println("Pencil writes some content: " + text);
+    }
+}

src/lab11_flyweight/ex1/Size.java

@@ -0,0 +1,6 @@
+package lab11_flyweight.ex1;
+
+public enum Size {
+    THIN,
+    THICK
+}

src/learn/simple_flyweight/ConcreteFlyweight.java

@@ -0,0 +1,15 @@
+package learn.simple_flyweight;
+
+public class ConcreteFlyweight extends Flyweight {
+    private long intrinsicState;
+
+    public ConcreteFlyweight(long intrinsicState) {
+        super();
+        this.intrinsicState = intrinsicState;
+    }
+
+    @Override
+    public void operation(long extrinsicState) {
+        System.out.println("Flyweight " + intrinsicState + " calling operation with extrinsic state " + extrinsicState);
+    }
+}

src/learn/simple_flyweight/Flyweight.java

@@ -0,0 +1,13 @@
+package learn.simple_flyweight;
+
+import java.util.Arrays;
+
+public abstract class Flyweight {
+    private long[] internalStorage = new long[1000000];
+
+    public Flyweight() {
+        Arrays.fill(internalStorage, 1);
+    }
+
+    public abstract void operation(long extrinsicState);
+}

src/learn/simple_flyweight/FlyweightFactory.java

@@ -0,0 +1,17 @@
+package learn.simple_flyweight;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class FlyweightFactory {
+    private static final Map<Integer, Flyweight> flyweights = new HashMap<>();
+
+    public Flyweight getFlyweight(Integer key) {
+        Flyweight flyweight = flyweights.get(key);
+        if (flyweight == null) {
+            flyweight = new ConcreteFlyweight(key);
+            flyweights.put(key, flyweight);
+        }
+        return flyweight;
+    }
+}

src/learn/simple_flyweight/Main.java

@@ -0,0 +1,40 @@
+package learn.simple_flyweight;
+
+import java.util.Random;
+
+public class Main {
+    private static final Random rand = new Random();
+
+    public static void main(String[] args) {
+        int rounds = 100;
+
+        debugMemory();
+        testFlyweight(rounds);
+        debugMemory();
+        testUnsharedFlyweight(rounds);
+        debugMemory();
+    }
+
+    private static void debugMemory() {
+        long totalMemory = Runtime.getRuntime().totalMemory();
+        long freeMemory = Runtime.getRuntime().freeMemory();
+        long usedMemory = totalMemory - freeMemory;
+        System.out.printf("Memory: %d%n", usedMemory);
+    }
+
+    private static void testFlyweight(int rounds) {
+        FlyweightFactory factory = new FlyweightFactory();
+
+        for (int i = 0; i < rounds; i++) {
+            Flyweight flyweight = factory.getFlyweight(rand.nextInt(10));
+            flyweight.operation(i);
+        }
+    }
+
+    private static void testUnsharedFlyweight(int rounds) {
+        for (int i = 0; i < rounds; i++) {
+            Flyweight flyweight = new UnsharedConcreteFlyweight(rand.nextInt(10));
+            flyweight.operation(i);
+        }
+    }
+}

src/learn/simple_flyweight/UnsharedConcreteFlyweight.java

@@ -0,0 +1,15 @@
+package learn.simple_flyweight;
+
+public class UnsharedConcreteFlyweight extends Flyweight {
+    private long allState;
+
+    public UnsharedConcreteFlyweight(long allState) {
+        super();
+        this.allState = allState;
+    }
+
+    @Override
+    public void operation(long extrinsicState) {
+        System.out.println("Unshared Flyweight " + allState + " calling operation with extrinsic state " + extrinsicState);
+    }
+}