建设自有网站需要什么,静态网站公用头部如何调用标题,重庆市建设工程人力资源网,中信建设证券网站目录 前言
一、结构中包含的角色
二、拦截器使用
1.拦截器角色 a.自定义拦截器UserValidateInterceptor#xff0c;UserUpdateInterceptor#xff0c;UserEditNameInterceptor b.拦截器配置者UserInterceptorChainConfigure#xff0c;任意组装拦截器顺序
c.拦截器管理者…
目录 前言
一、结构中包含的角色
二、拦截器使用
1.拦截器角色 a.自定义拦截器UserValidateInterceptorUserUpdateInterceptorUserEditNameInterceptor b.拦截器配置者UserInterceptorChainConfigure任意组装拦截器顺序
c.拦截器管理者UserInterceptorChainManager
2.运行结果展示
a.使用代码
三、拦截器调用解说
1.项目启动初始化bean
2.方法执行
四、代码下载
总结 前言
拦截过滤器模式,简称拦截器模式是责任链模式的一种衍生模式。用于对业务程序做一些预处理/后处理 一、结构中包含的角色
Interceptor抽象处理者InterceptorChain责任链InterceptorChainBuilder责任链建造者AbstractInterceptorChainManager链条管理者InterceptorChainConfigure链条配置者)二、拦截器使用
1.拦截器角色 a.自定义拦截器UserValidateInterceptorUserUpdateInterceptorUserEditNameInterceptor
/*** 校验用户* author liangxi.zeng*/
Component
public class UserValidateInterceptor implements InterceptorUser {/*** 拦截方法** param user*/Overridepublic void interceptor(User user) {if(user.getAge() ! 10) {throw new CommonException(年龄不对);}System.out.println(校验用户user);}
} b.拦截器配置者UserInterceptorChainConfigure任意组装拦截器顺序
Component
public class UserInterceptorChainConfigureimplements InterceptorChainConfigureUser,InterceptorChainBuilderUser {/*** 拦截器链配置** param interceptorChainBuilder 拦截器链构造器*/Overridepublic void configure(InterceptorChainBuilderUser interceptorChainBuilder) {interceptorChainBuilder.pre().addInterceptor(UserValidateInterceptor.class).post().addInterceptor(UserUpdateInterceptor.class).addInterceptor(UserEditNameInterceptor.class);}
}
c.拦截器管理者UserInterceptorChainManager
/*** author liangxi.zeng* 拦截器链管理类*/
Component
public class UserInterceptorChainManager
extends AbstractInterceptorChainManagerUser {public UserInterceptorChainManager(ListInterceptorUser interceptorList,ListInterceptorChainConfigureUser, InterceptorChainBuilderUser configureList) {super(interceptorList, configureList);}
}2.运行结果展示
a.使用代码
/*** author liangxi.zeng*/
RestController
RequestMapping(/demo)
public class DemoController {Autowiredprivate UserInterceptorChainManager userInterceptorChainManager;Autowiredprivate UserService userService;RequestMapping(/user)public String user() {User user new User();user.setId(111);user.setName(liangxi);user.setAge(10);userInterceptorChainManager.doInterceptor(user,(u) - {// 内部创建用户userService.save(user);});return success;}}三、拦截器调用解说
1.项目启动初始化bean
a.初始化责任链管理者UserInterceptorChainManager调用父类AbstractInterceptorChainManager方法initInterceptorChain通过责任链建造者初始化责任链 public AbstractInterceptorChainManager(ListInterceptorT interceptorList,ListInterceptorChainConfigureT, InterceptorChainBuilderT configureList) {interceptorChain initInterceptorChain(interceptorList, configureList);LOGGER.info(Register {} InterceptorChain, names are [{}],interceptorList);}private InterceptorChainT initInterceptorChain(ListInterceptorT interceptorList,ListInterceptorChainConfigureT, InterceptorChainBuilderT configureList) {if (CollectionUtils.isEmpty(interceptorList)) {throw new IllegalArgumentException(Interceptors is empty.);}if (CollectionUtils.isEmpty(configureList)) {throw new IllegalArgumentException(Interceptor configurers is empty.);}InterceptorChainBuilderT builder new InterceptorChainBuilder(interceptorList);configureList.sort(AnnotationAwareOrderComparator.INSTANCE);configureList.forEach(configurer - {configurer.configure(builder);});return builder.performBuild();} b.责任链建造者完成对业务方法前后逻辑的织入
public InterceptorChain performBuild() {ListInterceptorT preInterceptors filterInterceptor(preInterceptorList);ListInterceptorT postInterceptors filterInterceptor(postInterceptorList);if (preInterceptors.isEmpty() postInterceptors.isEmpty()) {throw new IllegalStateException(Registered Pre-Interceptors and Post-Interceptors is empty.);}ConsumerT preConsumer (T t) - {};ConsumerT postConsumer (T t) - {};if (!preInterceptors.isEmpty()) {preConsumer (T obj) - {for (InterceptorT item : preInterceptors) {item.interceptor(obj);}};}if (!postInterceptors.isEmpty()) {postConsumer (T obj) - {for (InterceptorT item : postInterceptors) {item.interceptor(obj);}};}return new InterceptorChain(preConsumer,postConsumer);}
2.方法执行
a.从userInterceptorChainManager.doInterceptor 到 interceptorChain.doExecute(target, operation);下面代码完成代码逻辑 /*** 拦截器调用入口将核心操作封装成 Consumer 对象传入。** param target The target to handle.* param operation The core operation to intercept.*/public final void doExecute(T target, OperationT operation) {preConsumer.accept(target);if (operation ! null) {operation.execute(target);}postConsumer.accept(target);}
四、代码下载
设计模式可运行代码https://gitee.com/zenglx/design-pattern.git 总结
前后端请求可以用现成的filter和spring的Interceptor解决业务自己的拦截器链模式可以解决繁琐业务重复代码的问题
