20200209 - springboot mvc configuration principle

Configuration

From Spring3.0, @ Configuration arranged for defining classes, alternatively xml configuration file, the internal class annotated with one or more methods are annotated @Bean, these methods will be AnnotationConfigApplicationContext AnnotationConfigWebApplicationContext classes or scanning, and with to build bean definition, initialization Spring container.

Normally, before we were Springmvc configuration is that,

  @Test
    public void  run1(){
        //加载配置文件
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
        //获取对象
        AccountService accountService = (AccountService) applicationContext.getBean("accountService");
        //调用方法
        accountService.findAll();
    }

@Configuration marked on the class, such as a spring corresponding to the xml configuration file, function as: a container disposed spring (application context)

package com.dxz.demo.configuration;

import org.springframework.context.annotation.Configuration;

@Configuration
public class TestConfiguration {
    public TestConfiguration() {
        System.out.println("TestConfiguration容器启动初始化。。。");
    }
}

Two codes are equivalent

package com.dxz.demo.configuration;

import org.springframework.context.annotation.Configuration;

@Configuration
public class TestConfiguration {
    public TestConfiguration() {
        System.out.println("TestConfiguration容器启动初始化。。。");
    }
}

If you want to diy a number of customized functions or just write this component, and then give it to springboot

springboot will help us to automate assembly

springboot of view resolver

package com.mmz.config;

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

import java.util.Locale;

/**
 * @Classname MyMvcConfig
 * @Description 全面接管/扩展Springmvc
 * @Date 2020/2/9 18:12
 * @Created by mmz
 */

@Configuration
public class MyMvcConfig  implements WebMvcConfigurer {

    @Bean
    public ViewResolver myMyViewResolver(){
        return new MyViewResolver();
    }

    //自定义了一个视图解析器
    public static class MyViewResolver implements ViewResolver{
        @Override
        public View resolveViewName(String s, Locale locale) throws Exception {
            return null;
        }
    }

}