@SuppressWarnings("unused")
    public boolean requiresDestruction(Object bean) {
        return (bean instanceof Destroyable);
    }
Return true only if <code>bean</code> implements Destroyable.

@param bean bean to check if requires destruction.
@return true only if <code>bean</code> implements Destroyable.
@since 1.4
support/spring/src/main/java/org/apache/shiro/spring/LifecycleBeanPostProcessor.java