bugfix: IllegalStateException in MotorcycleTest

src/main/java/com/github/stephengold/joltjni/VehicleConstraint.java

@@ -125,7 +125,8 @@ public VehicleCollisionTester getVehicleCollisionTester() {
     public Wheel getWheel(int wheelIndex) {
         long constraintVa = va();
         long wheelVa = getWheel(constraintVa, wheelIndex);
-        Wheel result = new Wheel(wheelVa);
+        int ordinal = Constraint.getControllerType(constraintVa);
+        Wheel result = Wheel.newWheel(wheelVa, ordinal);
 
         return result;
     }

src/main/java/com/github/stephengold/joltjni/Wheel.java

@@ -75,6 +75,35 @@ public ConstWheelSettings getSettings() {
         WheelSettings result = (WheelSettings) settings.getPtr();
         return result;
     }
+
+    /**
+     * Instantiate a {@code Wheel} from its virtual address.
+     *
+     * @param wheelVa the virtual address of the native object, or zero
+     * @param ordinal the type of {@code VehicleController}
+     * @return a new JVM object, or {@code null} if {@code wheelVa} was
+     * zero
+     */
+    public static Wheel newWheel(long wheelVa, int ordinal) {
+        if (wheelVa == 0L) {
+            return null;
+        }
+
+        Wheel result;
+        switch (ordinal) {
+            case VehicleController.motorcycleType:
+            case VehicleController.wheeledVehicleType:
+                result = new WheelWv(wheelVa);
+                break;
+            case VehicleController.trackedVehicleType:
+                result = new WheelTv(wheelVa);
+                break;
+            default:
+                throw new IllegalArgumentException("ordinal = " + ordinal);
+        }
+
+        return result;
+    }
     // *************************************************************************
     // native private methods
 

src/main/java/com/github/stephengold/joltjni/WheelTv.java

@@ -31,11 +31,12 @@ public class WheelTv extends Wheel {
     // constructors
 
     /**
-     * Instantiate with no native object assigned.
-     * <p>
-     * This no-arg constructor was made explicit to avoid javadoc warnings from
-     * JDK 18+.
+     * Instantiate with the specified native object assigned but not owned.
+     *
+     * @param wheelVa the virtual address of the native object to assign (not
+     * zero)
      */
-    WheelTv() {
+    WheelTv(long wheelVa) {
+        super(wheelVa);
     }
 }

src/main/java/com/github/stephengold/joltjni/WheelWv.java

@@ -31,11 +31,12 @@ public class WheelWv extends Wheel {
     // constructors
 
     /**
-     * Instantiate with no native object assigned.
-     * <p>
-     * This no-arg constructor was made explicit to avoid javadoc warnings from
-     * JDK 18+.
+     * Instantiate with the specified native object assigned but not owned.
+     *
+     * @param wheelVa the virtual address of the native object to assign (not
+     * zero)
      */
-    WheelWv() {
+    WheelWv(long wheelVa) {
+        super(wheelVa);
     }
 }