环境搭建

1.创建web项目

2.导入依赖

 <dependencies>
        <!--    单元测试-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>5.2.9.RELEASE</version>
        </dependency>

        <!--    数据库的连接-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.26</version>
        </dependency>

        <!--    spring mvc-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.2.9.RELEASE</version>
        </dependency>

        <!--    数据源-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.13</version>
        </dependency>

        <!--    json转换工具-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.76</version>
        </dependency>

<!--        <dependency>-->
<!--            <groupId>com.fasterxml.jackson.core</groupId>-->
<!--            <artifactId>jackson-databind</artifactId>-->
<!--            <version>2.9.5</version>-->
<!--        </dependency>-->
<!--        <dependency>-->
<!--            <groupId>com.fasterxml.jackson.core</groupId>-->
<!--            <artifactId>jackson-core</artifactId>-->
<!--            <version>2.9.5</version>-->
<!--        </dependency>-->
<!--        <dependency>-->
<!--            <groupId>com.fasterxml.jackson.core</groupId>-->
<!--            <artifactId>jackson-annotations</artifactId>-->
<!--            <version>2.9.5</version>-->
<!--        </dependency>-->

        <!--     jdbcTemplate-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.2.9.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.20</version>
        </dependency>

<!--        日志-->
<!--        <dependency>-->
<!--            <groupId>log4j</groupId>-->
<!--            <artifactId>log4j</artifactId>-->
<!--            <version>1.2.17</version>-->
<!--        </dependency>-->

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.1</version>
        </dependency>

3.配置tomcat








4.配置web.xml

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:applicationContext.xml</param-value>
  </context-param>

  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>

  <!--  配置post请求乱码问题-->
  <filter>
    <filter-name>CharacterEncodingFilter</filter-name>
    <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>UTF-8</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>CharacterEncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
  
  <servlet>
    <servlet-name>DispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:spring-mvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  
  <servlet-mapping>
    <servlet-name>DispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

springmvc集成fastson

配置springmvc的组件

<!--    转换：默认使用Json序列化工具jackson转换为fastson-->
    <mvc:annotation-driven>
<!--        消息转换器：不使用默认的jackson组件-->
        <mvc:message-converters register-defaults="true">
<!--            配置FastJson工具中的消息转换器类-->
            <bean id="fastJsonConverters" class="com.alibaba.fastjson.support.spring.FastJsonHttpMessageConverter">
<!--                消息转换器类中的字段赋值，支持的枚举类型-->
                <property name="supportedMediaTypes" >
                    <list>
                        <value>application/json;charset=utf-8</value>
                    </list>
                </property>
            </bean>
        </mvc:message-converters>
    </mvc:annotation-driven>

1.controller层

@ResponseBody
    @RequestMapping("/getAccount")
    public Account hello(){
    
    
        Account account = new Account();
        account.setId(1);
        account.setName("zhw");
        account.setMoney(3000d);
        return account;
    }

2.javeBean

package cn.zhw.springmvc_fastjson.domain;

import com.alibaba.fastjson.annotation.JSONType;
import com.alibaba.fastjson.serializer.SerializerFeature;
import lombok.Data;

@Data
//自定义序列化方案
@JSONType(
includes = {
    
    "id","name","money"},
orders = {
    
    "id","name","money"},
serialzeFeatures = {
    
    SerializerFeature.WriteMapNullValue,SerializerFeature.WriteNullStringAsEmpty})
public class Account {
    
    
    private Integer id;
    private String name;
    private Double money;
}

2.结果

注意的问题

关于返回json数据

springmvc默认使用的jackson返回json数据，所以需要我们导入相关的依赖

<dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.9.5</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.9.5</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.9.5</version>
        </dependency>

springMVC返回基本数据类型

springMVC返回基本数据类型不需要用到jsckson组件，可以正常返回，当返回javaBean时需要用到该组件，若不加入在依赖，则就会出现异常

    @ResponseBody
    @RequestMapping("/hello")
    public Account hello(){
    
    
        Account account = new Account();
        account.setId(1);
        account.setName("zhw");
        account.setMoney(3000d);
        return account;
    }