protected void addUnlinkedDescendants(Joint startBone,
            Collection<Joint> addResult) {
        for (Joint childBone : startBone.getChildren()) {
            String childName = childBone.getName();
            if (!hasBoneLink(childName)) {
                addResult.add(childBone);
                addUnlinkedDescendants(childBone, addResult);
            }
        }
    }
Add unlinked descendants of the specified bone to the specified
collection. Note: recursive.

@param startBone the starting bone (not null, unaffected)
@param addResult the collection of bone names to append to (not null,
modified)
jme3-jbullet/src/main/java/com/jme3/bullet/animation/DacConfiguration.java