资源速查-SSM整合-拦截器入门案例

推荐先阅读：Spring全家桶

1.制作拦截器功能类

2.配置拦截器的执行位置

// 声明拦截的bean，并实现HandlerInterceptor接口（注意：扫描加载bean）
@Component
public class ProjectInterceptor implements  HandlerInterceptor {
    public boolean preHandler(..) throws Exception {
        System.out.println("preHandler...");
    }
    public boolean postHandler(..) throws Exception {
        System.out.println("postHandler...");
    }
    public boolean afterCompletion(..) throws Exception {
        System.out.println("afterCompletion...");
    }
}

// 定义配置类，继承WebMvcConfigurationSupport，实现addInterceptor方法（注意：扫描加载bean）
@Configuration
public class SpringMvcSupport extends WebMvcConfigurationSupport {
    @Autowired
    private ProjectInterceptor projectInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry){
        // 添加拦截器并设定拦截的访问路径，路径可以通过可变参数设置多个
        registry.addInterceptor(projectInterceptor).addPathPatterns("/books");
    }
}

也可以使用标准接口WebMvcConfigure简化开发（注意：侵入性较强）

@Configuration
@ComponentScan("com.zx.controller")
@EnableWebMvc
public class SpringMvcConfig implements WebMvcConfigurer {
    @Autowired
    private ProjectInterceptor projectInterceptor;

    @Override
    public void addInterceptors(InterceptorRegistry registry){
        registry.addInterceptor(projectInterceptor).addPathPatterns("/books","/books/*");
    }
}

拦截器执行流程