一、概述
二、Spring使用
web.xml
文件中加入过滤器的代理类,targetBeanName
的值为过滤器的id
值。也就是@Component("authFilter")
中的authFilter
。
<!-- 统一认证过滤器的代理 -->
<filter>
<filter-name>DelegatingFilterProxy</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
<init-param>
<param-name>targetBeanName</param-name>
<param-value>authFilter</param-value>
</init-param>
<init-param>
<param-name>targetFilterLifecycle</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>DelegatingFilterProxy</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
@Component()
如果不带参数,默认值为类名首字母小写。
/**
* 统一认证过滤器
*/
@Component("authFilter")
public class AuthFilter implements Filter {
protected static final Logger logger = LoggerFactory.getLogger(AuthFilter.class);
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
HttpServletRequest httpRequest = (HttpServletRequest)request;
HttpServletResponse httpResponse = (HttpServletResponse)response;
HttpSession session = httpRequest.getSession();
}
}
三、SpringBoot使用
1、方法一
@WebFilter(filterName = "dataFilter", urlPatterns = "/api/*")
@Order(1)
public class DataFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
chain.doFilter(request, response);
}
@Override
public void destroy() {
}
}
在启动类上添加@ServletComponentScan
注解
//@ServletComponentScan({"com.scy.frame", "com.scy.app"})
@ServletComponentScan
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(VideoScreenApplication.class, args);
}
}
@ServletComponentScan作用
SpringBootApplication 上使用@ServletComponentScan 注解后
Servlet可以直接通过@WebServlet注解自动注册
Filter可以直接通过@WebFilter注解自动注册
Listener可以直接通过@WebListener 注解自动注册
2、方法二
不使用@WebFilter
方式声明过滤器,使用FilterRegistrationBean
在配置类中注入Filter
@Configuration
public class FilterConfiguration {
@Bean
public FilterRegistrationBean dataFilter(){
FilterRegistrationBean bean = new FilterRegistrationBean();
bean.setFilter(new DataFilter());
bean.setUrlPatterns(Arrays.asList("/api/*"));
bean.setOrder(6);//优先级,越低越优先
return bean;
}
}
3、方法三(有问题)
不再启动类添加@ServletComponentScan
注解,使用 @Component
或 @Configuration
导致urlPatterns
指定的拦截路径无法生效,出现拦截所有接口情况。
@Component
@WebFilter(filterName = "dataFilter", urlPatterns = "/api/*")
@Order(1)
public class DataFilter implements Filter {
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
chain.doFilter(request, response);
}
}