make optional fan characteristics... optional

since I'm "removing" characteristics here, Fan actually extends the "optional"
interfaces, and those optional interfaces have default "empty" implemenations,
so that compatibility is maintained, but an implementor can immediately start
using the new interface.

Author: ccutrer

src/main/java/com/beowulfe/hap/accessories/Fan.java

@@ -1,18 +1,20 @@
 package com.beowulfe.hap.accessories;
 
 import com.beowulfe.hap.*;
-import com.beowulfe.hap.accessories.properties.RotationDirection;
+import com.beowulfe.hap.accessories.characteristics.RotationDirection;
+import com.beowulfe.hap.accessories.characteristics.RotationSpeed;
 import com.beowulfe.hap.impl.services.FanService;
 import java.util.Collection;
 import java.util.Collections;
+import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
 
 /**
  * A fan, with power and rotational characteristics.
  *
  * @author Andy Lintner
  */
-public interface Fan extends HomekitAccessory {
+public interface Fan extends HomekitAccessory, RotationDirection, RotationSpeed {
 
   /**
    * Retrieves the current binary state of the fan's power.
@@ -21,20 +23,6 @@ public interface Fan extends HomekitAccessory {
    */
   CompletableFuture<Boolean> getFanPower();
 
-  /**
-   * Retrieves the current rotation direction of the fan.
-   *
-   * @return a future that will contain the direction
-   */
-  CompletableFuture<RotationDirection> getRotationDirection();
-
-  /**
-   * Retrieves the current speed of the fan's rotation
-   *
-   * @return a future that will contain the speed, expressed as an integer between 0 and 100.
-   */
-  CompletableFuture<Integer> getRotationSpeed();
-
   /**
    * Sets the binary state of the fan's power
    *
@@ -44,24 +32,6 @@ public interface Fan extends HomekitAccessory {
    */
   CompletableFuture<Void> setFanPower(boolean state) throws Exception;
 
-  /**
-   * Sets the rotation direction of the fan
-   *
-   * @param direction the direction to set
-   * @return a future that completes when the change is made
-   * @throws Exception when the change cannot be made
-   */
-  CompletableFuture<Void> setRotationDirection(RotationDirection direction) throws Exception;
-
-  /**
-   * Sets the speed of the fan's rotation
-   *
-   * @param speed the speed to set, expressed as an integer between 0 and 100.
-   * @return a future that completes when the change is made
-   * @throws Exception when the change cannot be made
-   */
-  CompletableFuture<Void> setRotationSpeed(Integer speed) throws Exception;
-
   @Override
   default Collection<Service> getServices() {
     return Collections.singleton(new FanService(this));
@@ -74,26 +44,16 @@ default Collection<Service> getServices() {
    */
   void subscribeFanPower(HomekitCharacteristicChangeCallback callback);
 
-  /**
-   * Subscribes to changes in the rotation direction of the fan.
-   *
-   * @param callback the function to call when the direction changes.
-   */
-  void subscribeRotationDirection(HomekitCharacteristicChangeCallback callback);
-
-  /**
-   * Subscribes to changes in the rotation speed of the fan.
-   *
-   * @param callback the function to call when the speed changes.
-   */
-  void subscribeRotationSpeed(HomekitCharacteristicChangeCallback callback);
-
   /** Unsubscribes from changes in the binary state of the fan's power. */
   void unsubscribeFanPower();
 
-  /** Unsubscribes from changes in the rotation direction of the fan. */
-  void unsubscribeRotationDirection();
+  /** returns the optional implementation of RotationDirection */
+  default Optional<RotationDirection> getRotationDirectionCharacteristic() {
+    return Optional.of(this);
+  }
 
-  /** Unsubscribes from changes in the fan's rotation speed. */
-  void unsubscribeRotationSpeed();
+  /** returns the optional implementation of RotationSpeed */
+  default Optional<RotationSpeed> getRotationSpeedCharacteristic() {
+    return Optional.of(this);
+  }
 }

src/main/java/com/beowulfe/hap/accessories/characteristics/RotationDirection.java

@@ -0,0 +1,39 @@
+package com.beowulfe.hap.accessories.characteristics;
+
+import com.beowulfe.hap.HomekitCharacteristicChangeCallback;
+import java.util.concurrent.CompletableFuture;
+
+public interface RotationDirection {
+  /**
+   * Retrieves the current rotation direction of the fan.
+   *
+   * @return a future that will contain the direction
+   */
+  default CompletableFuture<com.beowulfe.hap.accessories.properties.RotationDirection>
+      getRotationDirection() {
+    return CompletableFuture.completedFuture(
+        com.beowulfe.hap.accessories.properties.RotationDirection.CLOCKWISE);
+  }
+
+  /**
+   * Sets the rotation direction of the fan
+   *
+   * @param direction the direction to set
+   * @return a future that completes when the change is made
+   * @throws Exception when the change cannot be made
+   */
+  default CompletableFuture<Void> setRotationDirection(
+      com.beowulfe.hap.accessories.properties.RotationDirection direction) throws Exception {
+    return CompletableFuture.completedFuture(null);
+  }
+
+  /**
+   * Subscribes to changes in the rotation direction of the fan.
+   *
+   * @param callback the function to call when the direction changes.
+   */
+  default void subscribeRotationDirection(HomekitCharacteristicChangeCallback callback) {}
+
+  /** Unsubscribes from changes in the rotation direction of the fan. */
+  default void unsubscribeRotationDirection() {}
+}

src/main/java/com/beowulfe/hap/accessories/characteristics/RotationSpeed.java

@@ -0,0 +1,36 @@
+package com.beowulfe.hap.accessories.characteristics;
+
+import com.beowulfe.hap.HomekitCharacteristicChangeCallback;
+import java.util.concurrent.CompletableFuture;
+
+public interface RotationSpeed {
+  /**
+   * Retrieves the current speed of the fan's rotation
+   *
+   * @return a future that will contain the speed, expressed as an integer between 0 and 100.
+   */
+  default CompletableFuture<Integer> getRotationSpeed() {
+    return CompletableFuture.completedFuture(100);
+  }
+
+  /**
+   * Sets the speed of the fan's rotation
+   *
+   * @param speed the speed to set, expressed as an integer between 0 and 100.
+   * @return a future that completes when the change is made
+   * @throws Exception when the change cannot be made
+   */
+  default CompletableFuture<Void> setRotationSpeed(Integer speed) throws Exception {
+    return CompletableFuture.completedFuture(null);
+  }
+
+  /**
+   * Subscribes to changes in the rotation speed of the fan.
+   *
+   * @param callback the function to call when the speed changes.
+   */
+  default void subscribeRotationSpeed(HomekitCharacteristicChangeCallback callback) {}
+
+  /** Unsubscribes from changes in the fan's rotation speed. */
+  default void unsubscribeRotationSpeed() {}
+}

src/main/java/com/beowulfe/hap/impl/characteristics/fan/RotationDirectionCharacteristic.java

@@ -1,25 +1,25 @@
 package com.beowulfe.hap.impl.characteristics.fan;
 
 import com.beowulfe.hap.HomekitCharacteristicChangeCallback;
-import com.beowulfe.hap.accessories.Fan;
-import com.beowulfe.hap.accessories.properties.RotationDirection;
+import com.beowulfe.hap.accessories.characteristics.RotationDirection;
 import com.beowulfe.hap.characteristics.EnumCharacteristic;
 import com.beowulfe.hap.characteristics.EventableCharacteristic;
 import java.util.concurrent.CompletableFuture;
 
 public class RotationDirectionCharacteristic extends EnumCharacteristic
     implements EventableCharacteristic {
 
-  private final Fan fan;
+  private final RotationDirection fan;
 
-  public RotationDirectionCharacteristic(Fan fan) {
+  public RotationDirectionCharacteristic(RotationDirection fan) {
     super("00000028-0000-1000-8000-0026BB765291", true, true, "Rotation Direction", 1);
     this.fan = fan;
   }
 
   @Override
   protected void setValue(Integer value) throws Exception {
-    fan.setRotationDirection(RotationDirection.fromCode(value));
+    fan.setRotationDirection(
+        com.beowulfe.hap.accessories.properties.RotationDirection.fromCode(value));
   }
 
   @Override

src/main/java/com/beowulfe/hap/impl/characteristics/fan/RotationSpeedCharacteristic.java

@@ -1,17 +1,17 @@
 package com.beowulfe.hap.impl.characteristics.fan;
 
 import com.beowulfe.hap.HomekitCharacteristicChangeCallback;
-import com.beowulfe.hap.accessories.Fan;
+import com.beowulfe.hap.accessories.characteristics.RotationSpeed;
 import com.beowulfe.hap.characteristics.EventableCharacteristic;
 import com.beowulfe.hap.characteristics.IntegerCharacteristic;
 import java.util.concurrent.CompletableFuture;
 
 public class RotationSpeedCharacteristic extends IntegerCharacteristic
     implements EventableCharacteristic {
 
-  private final Fan fan;
+  private final RotationSpeed fan;
 
-  public RotationSpeedCharacteristic(Fan fan) {
+  public RotationSpeedCharacteristic(RotationSpeed fan) {
     super("00000029-0000-1000-8000-0026BB765291", true, true, "Rotation speed", 0, 100, "%");
     this.fan = fan;
   }

src/main/java/com/beowulfe/hap/impl/services/FanService.java

@@ -19,7 +19,9 @@ public FanService(Fan fan, String serviceName) {
             v -> fan.setFanPower(v),
             c -> fan.subscribeFanPower(c),
             () -> fan.unsubscribeFanPower()));
-    addCharacteristic(new RotationDirectionCharacteristic(fan));
-    addCharacteristic(new RotationSpeedCharacteristic(fan));
+    fan.getRotationDirectionCharacteristic()
+        .ifPresent(rotation -> addCharacteristic(new RotationDirectionCharacteristic(rotation)));
+    fan.getRotationSpeedCharacteristic()
+        .ifPresent(speed -> addCharacteristic(new RotationSpeedCharacteristic(speed)));
   }
 }