Create WeakHashMapDemo.java

rahulXbarnwal · web-flow · commit 510bc5a1eed1 · 2026-03-15T03:01:47.000+05:30
diff --git a/src/learnCollections/WeakHashMapDemo.java b/src/learnCollections/WeakHashMapDemo.java
@@ -0,0 +1,45 @@
+package learnCollections;
+
+import java.util.Map;
+import java.util.WeakHashMap;
+
+public class WeakHashMapDemo {
+    public static void main(String[] args) {
+        WeakHashMap<String, Image> imageCache = new WeakHashMap<>();
+        loadCache(imageCache);
+        System.out.println(imageCache); // {img1=Image 1, img2=Image 2}
+
+        System.gc();
+        simulateApplicationRunning();
+        System.out.println("Cache after running (some entries may be cleared): " + imageCache); // {}
+    }
+
+    public static void loadCache(Map<String, Image> imageCache) {
+        String k1 = new String("img1");
+        String k2 = new String("img2");
+        imageCache.put(k1, new Image("Image 1"));
+        imageCache.put(k2, new Image("Image 2"));
+    }
+
+    private static void simulateApplicationRunning() {
+        try {
+            System.out.println("Simulating application running...");
+            Thread.sleep(10000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+    }
+}
+
+class Image {
+    private String name;
+
+    public Image(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public String toString() {
+        return name;
+    }
+}
