added adapter example

src/learn/simple_adapter/Adaptee.java

@@ -0,0 +1,7 @@
+package learn.simple_adapter;
+
+public class Adaptee {
+    public void specificRequest() {
+        System.out.println("Specific Request");
+    }
+}

src/learn/simple_adapter/Adapter.java

@@ -0,0 +1,14 @@
+package learn.simple_adapter;
+
+public class Adapter implements Target {
+    private Adaptee adaptee;
+
+    public Adapter(Adaptee adaptee) {
+        this.adaptee = adaptee;
+    }
+
+    @Override
+    public void request() {
+        adaptee.specificRequest();
+    }
+}

src/learn/simple_adapter/Main.java

@@ -0,0 +1,9 @@
+package learn.simple_adapter;
+
+public class Main {
+    public static void main(String[] args) {
+        Adaptee adaptee = new Adaptee();
+        Target adapter = new Adapter(adaptee);
+        adapter.request();
+    }
+}

src/learn/simple_adapter/Target.java

@@ -0,0 +1,5 @@
+package learn.simple_adapter;
+
+public interface Target {
+    void request();
+}