SpringBoot擴展SpringMVC配置

官方文檔

@Configuration：可以使用自定義類擴展MVC的功能。

@EnableWebMvc：加上他SpringMVC自動配置全部失效。

 

自定義一個視圖解析器

自定義一個視圖解析器需要先實現ViewResolver接口。

自定義的視圖解析器MyMvcConfig類：

package com.lyr.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.util.Locale;

@Configuration
public class MyMvcConfig implements WebMvcConfigurer {
    @Bean //放到bean中
    public ViewResolver myViewResolver(){
        return new MyViewResolver();
    }

    //我們寫一個靜態內部類，視圖解析器就需要實現ViewResolver接口
    private static class MyViewResolver implements ViewResolver{
        @Override
        public View resolveViewName(String s, Locale locale) throws Exception {
            return null;
        }
    }
}

 

視圖跳轉

package com.lyr.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.util.Locale;

@Configuration
public class MyMvcConfig implements WebMvcConfigurer {
    //視圖跳轉
    @Override
    public void addViewControllers(ViewControllerRegistry registry) {
        //當訪問“/”時跳轉到“index”
        registry.addViewController("/").setViewName("index");
        registry.addViewController("/index.html").setViewName("index");
        registry.addViewController("/main.html").setViewName("dashboard");
    }
}

 

自定義攔截器

首先寫一個自定義攔截器的類LoginHandlerInterceptor ：

package com.lyr.config;

import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class LoginHandlerInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        Object loginUser = request.getSession().getAttribute("loginUser");

        if(loginUser==null){
            request.setAttribute("msg","沒有權限，請先登錄");
            request.getRequestDispatcher("/index.html").forward(request,response);
            return false;
        }
        return true;
    }
}

向容器中注入組件：

package com.lyr.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.LocaleResolver;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.ViewResolver;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;

import java.util.Locale;

@Configuration
public class MyMvcConfig implements WebMvcConfigurer {

    //攔截器
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        //addPathPatterns：攔截的，excludePathPatterns：不攔截的
        registry.addInterceptor(new LoginHandlerInterceptor()).addPathPatterns("/**")
                .excludePathPatterns("/index.html","/","/user/login","/css/**","/img/**","/js/**");
    }
}