public void afterPropertiesSet() throws Exception {
		Assert.hasLength(this.loginContextName,
				"loginContextName cannot be null or empty");
		Assert.notEmpty(this.authorityGranters,
				"authorityGranters cannot be null or empty");
		if (ObjectUtils.isEmpty(this.callbackHandlers)) {
			setCallbackHandlers(new JaasAuthenticationCallbackHandler[] {
					new JaasNameCallbackHandler(), new JaasPasswordCallbackHandler() });
		}
		Assert.notNull(this.loginExceptionResolver,
				"loginExceptionResolver cannot be null");
	}