#590 Add explanation for Adapter

adapter/src/main/java/com/iluwatar/adapter/App.java

@@ -34,14 +34,14 @@ package com.iluwatar.adapter;
  * object. This example uses the object adapter approach.
  *
  * <p>
- * The Adapter ({@link BattleFishingBoat}) converts the interface of the adaptee class (
- * {@link FishingBoat}) into a suitable one expected by the client ( {@link BattleShip} ).
+ * The Adapter ({@link FishingBoatAdapter}) converts the interface of the adaptee class (
+ * {@link FishingBoat}) into a suitable one expected by the client ( {@link RowingBoat} ).
  *
  * <p>
  * The story of this implementation is this. <br>
- * Pirates are coming! we need a {@link BattleShip} to fight! We have a {@link FishingBoat} and our
+ * Pirates are coming! we need a {@link RowingBoat} to flee! We have a {@link FishingBoat} and our
  * captain. We have no time to make up a new ship! we need to reuse this {@link FishingBoat}. The
- * captain needs a battleship which can fire and move. The spec is in {@link BattleShip}. We will
+ * captain needs a rowing boat which he can operate. The spec is in {@link RowingBoat}. We will
  * use the Adapter pattern to reuse {@link FishingBoat}.
  *
  */
@@ -53,8 +53,8 @@ public class App {
    * @param args command line args
    */
   public static void main(String[] args) {
-    Captain captain = new Captain(new BattleFishingBoat());
-    captain.move();
-    captain.fire();
+    // The captain can only operate rowing boats but with adapter he is able to use fishing boats as well
+    Captain captain = new Captain(new FishingBoatAdapter());
+    captain.row();
   }
 }

adapter/src/main/java/com/iluwatar/adapter/Captain.java

@@ -23,33 +23,26 @@
 package com.iluwatar.adapter;
 
 /**
- * The Captain uses {@link BattleShip} to fight. <br>
+ * The Captain uses {@link RowingBoat} to sail. <br>
  * This is the client in the pattern.
  */
-public class Captain implements BattleShip {
+public class Captain implements RowingBoat {
 
-  private BattleShip battleship;
+  private RowingBoat rowingBoat;
 
-  public Captain() {
+  public Captain() {}
 
+  public Captain(RowingBoat rowingBoat) {
+    this.rowingBoat = rowingBoat;
   }
 
-  public Captain(BattleShip battleship) {
-    this.battleship = battleship;
-  }
-
-  public void setBattleship(BattleShip battleship) {
-    this.battleship = battleship;
+  public void setRowingBoat(RowingBoat rowingBoat) {
+    this.rowingBoat = rowingBoat;
   }
 
   @Override
-  public void fire() {
-    battleship.fire();
-  }
-
-  @Override
-  public void move() {
-    battleship.move();
+  public void row() {
+    rowingBoat.row();
   }
 
 }

adapter/src/main/java/com/iluwatar/adapter/FishingBoat.java

@@ -27,7 +27,8 @@ import org.slf4j.LoggerFactory;
 
 /**
  *
- * Device class (adaptee in the pattern). We want to reuse this class
+ * Device class (adaptee in the pattern). We want to reuse this class.
+ * Fishing boat moves by sailing.
  *
  */
 public class FishingBoat {
@@ -35,11 +36,7 @@ public class FishingBoat {
   private static final Logger LOGGER = LoggerFactory.getLogger(FishingBoat.class);
 
   public void sail() {
-    LOGGER.info("The Boat is moving to that place");
-  }
-
-  public void fish() {
-    LOGGER.info("fishing ...");
+    LOGGER.info("The fishing boat is sailing");
   }
 
 }

adapter/src/main/java/com/iluwatar/adapter/FishingBoatAdapter.java

@@ -27,30 +27,22 @@ import org.slf4j.LoggerFactory;
 
 /**
  *
- * Adapter class. Adapts the interface of the device ({@link FishingBoat}) into {@link BattleShip}
- * interface expected by the client ({@link Captain}). <br>
- * In this case we added a new function fire to suit the interface. We are reusing the
- * {@link FishingBoat} without changing itself. The Adapter class can just map the functions of the
- * Adaptee or add, delete features of the Adaptee.
+ * Adapter class. Adapts the interface of the device ({@link FishingBoat}) into {@link RowingBoat}
+ * interface expected by the client ({@link Captain}).
  *
  */
-public class BattleFishingBoat implements BattleShip {
+public class FishingBoatAdapter implements RowingBoat {
 
-  private static final Logger LOGGER = LoggerFactory.getLogger(BattleFishingBoat.class);
+  private static final Logger LOGGER = LoggerFactory.getLogger(FishingBoatAdapter.class);
 
   private FishingBoat boat;
 
-  public BattleFishingBoat() {
+  public FishingBoatAdapter() {
     boat = new FishingBoat();
   }
 
   @Override
-  public void fire() {
-    LOGGER.info("fire!");
-  }
-
-  @Override
-  public void move() {
+  public void row() {
     boat.sail();
   }
 }

adapter/src/main/java/com/iluwatar/adapter/RowingBoat.java

@@ -24,13 +24,11 @@ package com.iluwatar.adapter;
 
 /**
  * The interface expected by the client.<br>
- * A Battleship can fire and move.
+ * A rowing boat is rowed to move.
  *
  */
-public interface BattleShip {
+public interface RowingBoat {
 
-  void fire();
-
-  void move();
+  void row();
 
 }

adapter/src/test/java/com/iluwatar/adapter/AdapterPatternTest.java

@@ -39,9 +39,9 @@ public class AdapterPatternTest {
 
   private Map<String, Object> beans;
 
-  private static final String BATTLESHIP_BEAN = "engineer";
+  private static final String FISHING_BEAN = "fisher";
 
-  private static final String CAPTAIN_BEAN = "captain";
+  private static final String ROWING_BEAN = "captain";
 
   /**
    * This method runs before the test execution and sets the bean objects in the beans Map.
@@ -50,34 +50,29 @@ public class AdapterPatternTest {
   public void setup() {
     beans = new HashMap<>();
 
-    BattleFishingBoat battleFishingBoat = spy(new BattleFishingBoat());
-    beans.put(BATTLESHIP_BEAN, battleFishingBoat);
+    FishingBoatAdapter fishingBoatAdapter = spy(new FishingBoatAdapter());
+    beans.put(FISHING_BEAN, fishingBoatAdapter);
 
     Captain captain = new Captain();
-    captain.setBattleship((BattleFishingBoat) beans.get(BATTLESHIP_BEAN));
-    beans.put(CAPTAIN_BEAN, captain);
+    captain.setRowingBoat((FishingBoatAdapter) beans.get(FISHING_BEAN));
+    beans.put(ROWING_BEAN, captain);
   }
 
   /**
-   * This test asserts that when we use the move() method on a captain bean(client), it is
-   * internally calling move method on the battleship object. The Adapter ({@link BattleFishingBoat}
+   * This test asserts that when we use the row() method on a captain bean(client), it is
+   * internally calling sail method on the fishing boat object. The Adapter ({@link FishingBoatAdapter}
    * ) converts the interface of the target class ( {@link FishingBoat}) into a suitable one
    * expected by the client ({@link Captain} ).
    */
   @Test
   public void testAdapter() {
-    BattleShip captain = (BattleShip) beans.get(CAPTAIN_BEAN);
+    RowingBoat captain = (RowingBoat) beans.get(ROWING_BEAN);
 
     // when captain moves
-    captain.move();
+    captain.row();
 
     // the captain internally calls the battleship object to move
-    BattleShip battleship = (BattleShip) beans.get(BATTLESHIP_BEAN);
-    verify(battleship).move();
-
-    // same with above with firing
-    captain.fire();
-    verify(battleship).fire();
-
+    RowingBoat adapter = (RowingBoat) beans.get(FISHING_BEAN);
+    verify(adapter).row();
   }
 }