@Override
    public void write(JmeExporter e) throws IOException {
        super.write(e);
        OutputCapsule capsule = e.getCapsule(this);
        capsule.write(stepHeight, "stepHeight", 1.0f);
        capsule.write(getGravity(), "gravity", 9.8f * 3);
        capsule.write(getMaxSlope(), "maxSlope", 1.0f);
        capsule.write(fallSpeed, "fallSpeed", 55.0f);
        capsule.write(jumpSpeed, "jumpSpeed", 10.0f);
        capsule.write(upAxis, "upAxis", 1);
        capsule.write(getCcdMotionThreshold(), "ccdMotionThreshold", 0);
        capsule.write(getCcdSweptSphereRadius(), "ccdSweptSphereRadius", 0);
        capsule.write(getPhysicsLocation(new Vector3f()), "physicsLocation", new Vector3f());
    }
used internally

@return the pre-existing object
jme3-jbullet/src/main/java/com/jme3/bullet/objects/PhysicsCharacter.java