Added AbstractMovementTarget and a terminate method.

Prepping for a new release.

Author: pspeed42

build.gradle

@@ -14,7 +14,7 @@ buildscript {
 apply plugin: 'java'
 apply plugin: 'maven'
 
-version='1.4.1-SNAPSHOT'
+version='1.5.0'
 group='com.simsilica'
 
 ext.jmeVersion = "3.2.1-stable"

release-notes.md

@@ -1,7 +1,9 @@
-Version 1.4.1 (unreleased)
+Version 1.5.0 (unreleased)
 --------------
-* Added an initialize method to MovementTarget for the MovementState to
+* Added an initialize and terminate methods to MovementTarget for the MovementState to
     call when the target is set.
+* Added an AbstractMovementTarget class to shield subclasses from future interface
+    changes.
 
 
 Version 1.4.0 (latest)

src/main/java/com/simsilica/input/AbstractMovementTarget.java

@@ -0,0 +1,61 @@
+/*
+ * $Id$
+ *
+ * Copyright (c) 2020, Simsilica, LLC
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+ * OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package com.simsilica.input;
+
+import com.simsilica.mathd.*;
+
+/**
+ *
+ *
+ *  @author    Paul Speed
+ */
+public abstract class AbstractMovementTarget implements MovementTarget {
+
+    /**
+     *  Default implementation does nothing.
+     */
+    @Override
+    public void initialize( MovementState state ) {
+    }
+    
+    /**
+     *  Default implementation does nothing.
+     */
+    @Override
+    public void terminate( MovementState state ) {
+    }
+}

src/main/java/com/simsilica/input/CameraMovementTarget.java

@@ -47,7 +47,7 @@
  *
  *  @author    Paul Speed
  */
-public class CameraMovementTarget implements MovementTarget {
+public class CameraMovementTarget extends AbstractMovementTarget {
 
     private Camera camera;
     private boolean relativeForward = true;
@@ -90,10 +90,6 @@ public boolean isRelativeUp() {
         return relativeUp;
     }
 
-    @Override
-    public void initialize( MovementState state ) {
-    }
-
     @Override
     public void move( Quatd rotation, Vec3d movementForces, double tpf ) {
         if( movementForces.lengthSq() == 0 ) {

src/main/java/com/simsilica/input/MovementState.java

@@ -91,6 +91,9 @@ public MovementState() {
      *  target has been provided.
      */
     public void setMovementTarget( MovementTarget target ) {
+        if( this.target != null ) {
+            this.target.terminate(this);
+        }
         this.target = target;
         target.initialize(this);
         initializeRotation(target.getRotation());

src/main/java/com/simsilica/input/MovementTarget.java

@@ -49,6 +49,11 @@ public interface MovementTarget {
      *  Called when the target is first set to the MovementState.
      */
     public void initialize( MovementState state );
+    
+    /**
+     *  Called when the target is removed/replace in the MovementState.
+     */
+    public void terminate( MovementState state );
 
     /**
      *  Called once per frame to let the target update its position