通过拦截器创建一个登录小案例

Myth丶恋晨 2023-10-11 19:52 10阅读 0赞

## 一、定义拦截器 ##

### 1.1、创建Java类继承自WebMvcConfigurerAdapter，并通过@Configruation注解进行标注 ###

![f78ecd51788f4a5eb1cfbe16062ed183.png][]

### 1.2、重写父类addInterceptors方法，创建HandlerInterceptor对象 ###

**这里案例是类似一个登录系统,账号是admin,密码是123**

![6ee6bd1e893d4df08c08b7186b56a968.png][]

package demo.interceptor;
    
    import demo.controller.TestController;
    import org.springframework.context.annotation.Configuration;
    import org.springframework.web.servlet.HandlerInterceptor;
    import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
    import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
    
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.io.PrintWriter;
    
    @Configuration
    public class MyInterceptor extends WebMvcConfigurerAdapter {
        @Override
        public void addInterceptors(InterceptorRegistry registry) {
            HandlerInterceptor handlerInterceptor = new HandlerInterceptor() {
                 /**
                 * 拦截请求的方法
                 */
                @Override
                public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
                    request.setCharacterEncoding("utf-8");
                    response.setCharacterEncoding("utf-8");
                    response.setContentType("text/html;charset=utf-8");
                    String name = request.getParameter("name");
                    String passwd = request.getParameter("passwd");
                    if (name.equals("admin")&&passwd.equals("123")){
                        return true;
                    }else{
                        return false;
                    }
                    //true=放行；false=拦截（直接大白页）
                }
            };
            registry.addInterceptor(handlerInterceptor).addPathPatterns("/**");
        }
    }

### 1.3、在addInterceptors方法中，将HandlerInterceptor对象放到InterceptorRegistry对象中，并通过addPathPatterns方法定义拦截规则 ###

registry.addInterceptor(handlerInterceptor).addPathPatterns("/**"); //拦截一切请求

### 二、全部源代码 ###

[f78ecd51788f4a5eb1cfbe16062ed183.png]: https://img-blog.csdnimg.cn/f78ecd51788f4a5eb1cfbe16062ed183.png
[6ee6bd1e893d4df08c08b7186b56a968.png]: https://img-blog.csdnimg.cn/6ee6bd1e893d4df08c08b7186b56a968.png