springMvc

 

1.情况1

 

 2.引入fastjson依赖

springmvc.xml配置

<!-- 转换器  把返回结果转换成字符串  不能将ArrayList转为json
         这种方式适合返回String 
     -->
   <mvc:annotation-driven >
        <mvc:message-converters register-defaults="false">
            <bean class="org.springframework.http.converter.StringHttpMessageConverter">  
                <constructor-arg value="UTF-8" />
            </bean>  
        </mvc:message-converters>    
    </mvc:annotation-driven> 

 

 

成功返回list数据

 

 

3.springMvc目测不支持直接返回List自动转换成json，要手动转换。

 

4.在springmvc.xml配置 

 <mvc:annotation-driven>
        <mvc:message-converters>
            <bean class="org.springframework.http.converter.StringHttpMessageConverter"/>
            <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"/>
        </mvc:message-converters>
    </mvc:annotation-driven>
 

注意：

spring3.x是org.springframework.http.converter.json.MappingJacksonHttpMessageConverter

spring4.x是org.springframework.http.converter.json.MappingJackson2HttpMessageConverter

5.要想直接把List等直接转换成json

步骤一：

引入依赖

    <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.9.7</version>
    </dependency>
    
    <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>2.9.7</version>
    </dependency>

步骤二：

在springmvc.xml加入

 <mvc:annotation-driven>
        <mvc:message-converters>
            <bean class="org.springframework.http.converter.StringHttpMessageConverter"/>
            <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"/>
        </mvc:message-converters>
    </mvc:annotation-driven>
 

步骤三：

import java.util.List;


import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.alibaba.dubbo.config.annotation.Reference;
import com.pinyougou.pojo.TbBrand;
import com.pinyougou.sellergoods.service.BrandService;

@RestController
@RequestMapping("/brand")
public class BrandController {

    @Reference
    private BrandService brandService;
    

    @RequestMapping("/findAll")
    public List<TbBrand> findAll(){
        return brandService.findAll();
    }
    
    /*    @RequestMapping("/findAll")
    public String findAll(){
        List<TbBrand> list = brandService.findAll();
        
        return JSON.toJSONString(list);
    }*/
}