Filter中注入spring
?????? 当我们用Filter时，往往需要使用一些辅助的service，在普通的java中，只要声明（set,get方法）后在spring-application配置文件中配置就可以了，但是由于Filter与Listener需要配置在web.xml文件中，所以它们的对象是由容器创建的。通常在Spring的application-context.xml配置文件中编写的bean由Spring负责创建，所以直接在Spring配置文件配置过滤器与监听器是无法达到注入目的的。
??????? 可以使用如下方法，例：
public class JudgeUserRole implements Filter {private UserRelationService userRelationService;public UserRelationService getUserRelationService() {return userRelationService;}public void setUserRelationService(UserRelationService userRelationService) {this.userRelationService = userRelationService;}@Overridepublic void destroy() {}@Overridepublic void doFilter(ServletRequest arg0, ServletResponse arg1,FilterChain arg2) throws IOException, ServletException { UserRelationship user = this.userRelationService.checkRelationship(0, "jnduan", 0, "cscs01"); }@Overridepublic void init(FilterConfig config) throws ServletException { ServletContext context = config.getServletContext();ApplicationContext ctx = WebApplicationContextUtils.getWebApplicationContext(context);userRelationService = (UserRelationService) ctx.getBean("userRelationService");}}?? ps: userRelationService为在spring-application中配置的
public class MyFilter implements Filter, ApplicationContextAware {private AccountManager accountManager;@Override@PostConstructpublic void init(FilterConfig filterConfig) throws ServletException {// TODO Auto-generated method stub}@Overridepublic void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {// TODO Auto-generated method stub}@Overridepublic void destroy() {// TODO Auto-generated method stub}@Overridepublic void setApplicationContext(ApplicationContext applicationContext) throws BeansException {accountManager = applicationContext.getBean(AccountManager.class);}}