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Author: disha2sinha

Interface/Interface1.java

@@ -0,0 +1,37 @@
+package Interface;
+interface Callback {
+    void call(int person);
+
+}
+
+class Client implements Callback {
+    public void call(int p) {
+        System.out.println("Call p:" + p);
+    }
+
+    void nonInterface() {
+        System.out.println("NonInterface method");
+    }
+}
+
+class AnotherClient implements Callback {
+    public void call(int p) {
+        System.out.println("p*p=" + (p * p));
+    }
+}
+
+public class Interface1 {
+
+    public static void main(String[] args) {
+        Callback c = new Client();
+        c.call(43);
+        // c.nonInterface(); will generate error as the reference variable is not class
+        // type.
+        Client ob = new Client();
+        ob.nonInterface();
+        AnotherClient obj = new AnotherClient();
+        c = obj;
+        c.call(9);
+
+    }
+}