BAEL-1072 - Difference between Proxy, Decorator, Adapter, and Bridge (Update) (#2518)

* Removing old code

* Removing old code

* Removing old code

* Removing old code

* Updated design for Adapter pattern

* Updated test cases for new design

core-java/src/main/java/com/baeldung/designpatterns/adapter/AdapterPatternDriver.java

@@ -5,9 +5,16 @@ import static com.baeldung.designpatterns.util.LogerUtil.LOG;
 public class AdapterPatternDriver {
     
     public static void main(String args[]) {
-        LuxuryCarsSpeedAdapter luxuryCars = new LuxuryCarsSpeedAdapterImpl();
+        LuxuryCars bugattiVeyron = new BugattiVeyron();
-        LOG.info("Bugatti Veyron Super Sport's top speed is " + luxuryCars.bugattiVeyronInKMPH() + " Kmph.");
+        LuxuryCarsAdapter bugattiVeyronAdapter = new LuxuryCarsAdapterImpl(bugattiVeyron);
-        LOG.info("McLaren F1 top speed is " + luxuryCars.mcLarenInKMPH() + " Kmph.");
+        LOG.info("Bugatti Veyron Super Sport's top speed is " + bugattiVeyronAdapter.speedInKMPH() + " Kmph.");
-        LOG.info("Aston Martin One-77 top speed is " + luxuryCars.astonMartinInKMPH() + " Kmph.");
+
+        LuxuryCars mcLaren = new McLaren();
+        LuxuryCarsAdapter mcLarenAdapter = new LuxuryCarsAdapterImpl(mcLaren);
+        LOG.info("McLaren F1 top speed is " + mcLarenAdapter.speedInKMPH() + " Kmph.");
+
+        LuxuryCars astonMartin = new AstonMartin();
+        LuxuryCarsAdapter astonMartinAdapter = new LuxuryCarsAdapterImpl(astonMartin);
+        LOG.info("McLaren F1 top speed is " + astonMartinAdapter.speedInKMPH() + " Kmph.");
     }
 }

core-java/src/main/java/com/baeldung/designpatterns/adapter/AstonMartin.java

@@ -0,0 +1,8 @@
+package com.baeldung.designpatterns.adapter;
+
+public class AstonMartin implements LuxuryCars {
+    @Override
+    public double speedInMPH() {
+        return 220;
+    }
+}

core-java/src/main/java/com/baeldung/designpatterns/adapter/BugattiVeyron.java

@@ -0,0 +1,8 @@
+package com.baeldung.designpatterns.adapter;
+
+public class BugattiVeyron implements LuxuryCars {
+    @Override
+    public double speedInMPH() {
+        return 268;
+    }
+}

core-java/src/main/java/com/baeldung/designpatterns/adapter/LuxuryCars.java

@@ -0,0 +1,5 @@
+package com.baeldung.designpatterns.adapter;
+
+public interface LuxuryCars {
+    public double speedInMPH();
+}

core-java/src/main/java/com/baeldung/designpatterns/adapter/LuxuryCarsAdapter.java

@@ -0,0 +1,5 @@
+package com.baeldung.designpatterns.adapter;
+
+public interface LuxuryCarsAdapter {
+    public double speedInKMPH();
+}

core-java/src/main/java/com/baeldung/designpatterns/adapter/LuxuryCarsAdapterImpl.java

@@ -0,0 +1,19 @@
+package com.baeldung.designpatterns.adapter;
+
+public class LuxuryCarsAdapterImpl implements LuxuryCarsAdapter {
+    private LuxuryCars luxuryCars;
+    
+    public LuxuryCarsAdapterImpl(LuxuryCars luxuryCars) {
+        this.luxuryCars = luxuryCars;
+    }
+
+    @Override
+    public double speedInKMPH() {
+        double mph = luxuryCars.speedInMPH();
+        return convertMPHtoKMPH(mph);
+    }
+    
+    private double convertMPHtoKMPH(double mph) {
+        return mph * 1.60934;
+    }
+}

core-java/src/main/java/com/baeldung/designpatterns/adapter/LuxuryCarsSpeed.java

@@ -1,15 +0,0 @@
-package com.baeldung.designpatterns.adapter;
-
-public class LuxuryCarsSpeed {
-    public double bugattiVeyronInMPH() {
-        return 268;
-    }
-
-    public double mcLarenInMPH() {
-        return 241;
-    }
-
-    public double astonMartinInMPH() {
-        return 220;
-    }
-}

core-java/src/main/java/com/baeldung/designpatterns/adapter/LuxuryCarsSpeedAdapter.java

@@ -1,9 +0,0 @@
-package com.baeldung.designpatterns.adapter;
-
-public interface LuxuryCarsSpeedAdapter {
-    public double bugattiVeyronInKMPH();
-
-    public double mcLarenInKMPH();
-
-    public double astonMartinInKMPH();
-}

core-java/src/main/java/com/baeldung/designpatterns/adapter/LuxuryCarsSpeedAdapterImpl.java

@@ -1,26 +0,0 @@
-package com.baeldung.designpatterns.adapter;
-
-public class LuxuryCarsSpeedAdapterImpl extends LuxuryCarsSpeed implements LuxuryCarsSpeedAdapter {
-
-    @Override
-    public double bugattiVeyronInKMPH() {
-        double mph = super.bugattiVeyronInMPH();
-        return convertMPHtoKMPH(mph);
-    }
-
-    @Override
-    public double mcLarenInKMPH() {
-        double mph = super.mcLarenInMPH();
-        return convertMPHtoKMPH(mph);
-    }
-
-    @Override
-    public double astonMartinInKMPH() {
-        double mph = super.astonMartinInMPH();
-        return convertMPHtoKMPH(mph);
-    }
-
-    private double convertMPHtoKMPH(double mph) {
-        return mph * 1.60934;
-    }
-}

core-java/src/main/java/com/baeldung/designpatterns/adapter/McLaren.java

@@ -0,0 +1,8 @@
+package com.baeldung.designpatterns.adapter;
+
+public class McLaren implements LuxuryCars {
+    @Override
+    public double speedInMPH() {
+        return 241;
+    }
+}

core-java/src/test/java/com/baeldung/designpatterns/AdapterPatternIntegrationTest.java

@@ -1,20 +1,20 @@
 package com.baeldung.designpatterns;
 
-
+import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.*;
 
 import org.junit.Test;
 
-import com.baeldung.designpatterns.adapter.LuxuryCarsSpeedAdapter;
+import com.baeldung.designpatterns.adapter.AstonMartin;
-import com.baeldung.designpatterns.adapter.LuxuryCarsSpeedAdapterImpl;
+import com.baeldung.designpatterns.adapter.BugattiVeyron;
+import com.baeldung.designpatterns.adapter.LuxuryCarsAdapterImpl;
+import com.baeldung.designpatterns.adapter.McLaren;
 
 public class AdapterPatternIntegrationTest {
     @Test
     public void givenLuxuryCarsAdapter_WhenConvertingMPHToKMPH_thenSuccessfullyConverted() {
-        LuxuryCarsSpeedAdapter luxuryCars = new LuxuryCarsSpeedAdapterImpl();
+        assertEquals(new LuxuryCarsAdapterImpl(new BugattiVeyron()).speedInKMPH(), 431.30312, 0.00001);
-        assertEquals(luxuryCars.bugattiVeyronInKMPH(), 431.30312, 0.00001);
+        assertEquals(new LuxuryCarsAdapterImpl(new McLaren()).speedInKMPH(), 387.85094, 0.00001);
-        assertEquals(luxuryCars.mcLarenInKMPH(), 387.85094, 0.00001);
+        assertEquals(new LuxuryCarsAdapterImpl(new AstonMartin()).speedInKMPH(), 354.0548, 0.00001);
-        assertEquals(luxuryCars.astonMartinInKMPH(), 354.0548, 0.00001);
     }
 }