tomcat容器初始化順序監聽器–>過濾器–>servlet，因此springMVCservlet初始化之前，過濾器就已經初始化過了，如果在過濾器中需要註入spring容器管理的bean是註入不進去的，因此需要在spring監聽器中初始化需要註入的bean，才能在過濾器中註入，而且過濾器的定義需要使用spring定義的DelegatingFilterProxy來實現，web.xml部分代碼如下

<filter>
        <filter-name>testFilter</filter-name>
        <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>testFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
 

其余部分只需要在spring容器中加載testFilter就行了，例子testFilter如下：
註意此處的filter必須為實現javax.Filter的類，而且初始化需要放在spring監聽器中，即必須在過濾器初始化之前初始化

@Component
public class TestFilter implements Filter
{
    private static final Logger logger = LogManager.getLogger(TestFilter.class);

    @Autowired
    private UserService userService;

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
        throws ServletException, IOException
    {
        logger.info(JSONArray.fromObject(userService.list()));
        filterChain.doFilter(request, response);
    }

    @Override
    public void init(FilterConfig filterConfig)
        throws ServletException
    {
        logger.info("初始化filter");
    }

    @Override
    public void destroy()
    {
        logger.info("destroyfilter");
    }
}
 

如果要保留Filter原有的init，destroy方法的調用，還需要配置初始化參數targetFilterLifecycle為true，該參數默認為false，代碼例子如下：

<filter>
        <filter-name>testFilter</filter-name>
        <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
        <init-param>
            <param-name>targetFilterLifecycle</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>testFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
 

filter加載springbean