From baff959dd3b3249dd0095073ffb216c1b0a9ebaa Mon Sep 17 00:00:00 2001
From: Hammy <sgoudham@gmail.com>
Date: Wed, 16 Dec 2020 00:07:53 +0000
Subject: [PATCH] Combine Singleton + Adapter

---
 .../src/adapter/animal/BirdAdapter.java            | 14 ++++++++++++--
 Design Patterns/src/adapter/animal/Main.java       |  2 +-
 .../src/adapter/animal/tests/BirdAdapterTest.java  |  2 +-
 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/Design Patterns/src/adapter/animal/BirdAdapter.java b/Design Patterns/src/adapter/animal/BirdAdapter.java
index d22bdb9..aeb362c 100644
--- a/Design Patterns/src/adapter/animal/BirdAdapter.java	
+++ b/Design Patterns/src/adapter/animal/BirdAdapter.java	
@@ -2,12 +2,22 @@ package adapter.animal;
 
 public class BirdAdapter implements ToyDuck {
 
-    private final Bird bird;
+    private Bird bird;
+    private static BirdAdapter instance;
 
-    public BirdAdapter(Bird bird) {
+    private BirdAdapter(Bird bird) {
         this.bird = bird;
     }
 
+    public static BirdAdapter getInstance(Bird bird) {
+        if (instance == null) {
+            instance = new BirdAdapter(bird);
+        } else if (!instance.bird.equals(bird)) {
+            instance.bird = bird;
+        }
+        return instance;
+    }
+
     @Override
     public void squeak() {
         bird.makeSound();
diff --git a/Design Patterns/src/adapter/animal/Main.java b/Design Patterns/src/adapter/animal/Main.java
index 2f9fa9e..ac87451 100644
--- a/Design Patterns/src/adapter/animal/Main.java	
+++ b/Design Patterns/src/adapter/animal/Main.java	
@@ -14,7 +14,7 @@ public class Main {
         plasticToyDuck.squeak();
 
         System.out.println("\nBirdAdapter...");
-        ToyDuck birdAdapter = new BirdAdapter(sparrow);
+        ToyDuck birdAdapter = BirdAdapter.getInstance(sparrow);
         birdAdapter.squeak();
 
     }
diff --git a/Design Patterns/src/adapter/animal/tests/BirdAdapterTest.java b/Design Patterns/src/adapter/animal/tests/BirdAdapterTest.java
index 69849d8..352f004 100644
--- a/Design Patterns/src/adapter/animal/tests/BirdAdapterTest.java	
+++ b/Design Patterns/src/adapter/animal/tests/BirdAdapterTest.java	
@@ -13,7 +13,7 @@ class BirdAdapterTest {
     @Test
     void verifyMakeSoundIsCalled() {
         Bird mockedSparrow = mock(Sparrow.class);
-        ToyDuck birdAdapter = new BirdAdapter(mockedSparrow);
+        ToyDuck birdAdapter = BirdAdapter.getInstance(mockedSparrow);
 
         birdAdapter.squeak();
         verify(mockedSparrow, times(1)).makeSound();