使用@RequestBody传递多个不同对象方式代码示例

作者:袖梨 2022-06-29

本篇文章小编给大家分享一下使用@RequestBody传递多个不同对象方式代码示例,文章代码介绍的很详细,小编觉得挺不错的,现在分享给大家供大家参考,有需要的小伙伴们可以来看看。

@RequestBody传递多个不同对象

如果使用spring mvc同客户端通信,完全使用json数据格式,需要增加RequestBody注解,函数参数为自定义类

@Controller
public class TestController{
  @RequestMapping("test")
  @ResponseBody
  public RetureResult test(@RequestBody User user){
    return new ReturnResult();
  }  
}

这样的话,可以将接收到的json格式的数据转换为指定的数据对象user。比如{name:"test"},name为User类的属性域。通过ResponseBody注解,可以返回json格式的数据。

有时接收json格式数据时,我们可能需要将其转换为多个对象。

以下方式是错误的。原因是request的content-body是以流的形式进行读取的,读取完一次后,便无法再次读取了。

@Controller
public class TestController{
  @RequestMapping("test")
  @ResponseBody
  public RetureResult test(@RequestBody User user,@RequestBody Address address){
    return new ReturnResult();
  }  
}

解决方案1

增加一个包装类,将所需要类写入,增加get,set方法

@Controller
public class TestController{
  @RequestMapping("test")
  @ResponseBody
  public RetureResult test(@RequestBody Param param){
    User user=param.getUser();
    Address address=param.getAddress();
    return new ReturnResult();
  }  
}
class Param{
 
    private User user;
    private Address address;  
 
    public User getUser() {
        return user;
    }
 
    public void setUser(User user) {
        this.user = user;
    }
 
    public Address getAddress() {
        return address;
    }
 
    public void setAddress(Address address) {
        this.address = address;
    }
}

此时传输的json数据格式变为{user:{name:"test"},address:{location:"新华路"}}。

由于只是在TestController中增加一个包装类,不会影响其他的类以及已经定义好的model类,因此可以非常方便的达到接收多个对象参数的目的。

解决方案2

将接收参数定义为Map,然后使用map转object工具,转换成需要的对象。

此时,即使自定义的Param类中的属性即使比json数据中的属性少了,也没关系。

其中JSONUtils为自定义的工具类,可使用常见的fastjson等工具包包装实现。

@Controller
public class TestController{
  @RequestMapping("test")
  @ResponseBody
  public Object test(@RequestBody Map models){
   User user=JsonXMLUtils.map2object((Map)models.get("user"),User.class); 
   Address address=JsonXMLUtils.map2object((Map)models.get("address"),Address.class); 
   return models; 
 }
}
import com.alibaba.fastjson.JSON;
 
public class JsonXMLUtils {
    public static String obj2json(Object obj) throws Exception {
        return JSON.toJSONString(obj);
    }
 
    public static  T json2obj(String jsonStr, Class clazz) throws Exception {
        return JSON.parseObject(jsonStr, clazz);
    }
 
    public static  Map json2map(String jsonStr)     throws Exception {
            return JSON.parseObject(jsonStr, Map.class);
    }
  
    public static  T map2obj(Map map, Class clazz) throws Exception {
        return JSON.parseObject(JSON.toJSONString(map), clazz);
    }
}

使用多个@RequestBody接收参数

原因

常规情况下,因为request的body只能读取一次,@RequestBody也只能解析一次,这就导致解析第二个的@RequestBody的时候stream已经关闭了,无法再次读取。

话不多说,上货:

解决办法:两个类,直接copy即可

import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*; 
public class BodyReaderRequestWrapper extends HttpServletRequestWrapper {
    private final String body;
 
    /**
     *
     * @param request
     */
    public BodyReaderRequestWrapper(HttpServletRequest request) throws IOException{
        super(request);
        StringBuilder sb = new StringBuilder();
        InputStream ins = request.getInputStream();
        BufferedReader isr = null;
        try{
            if(ins != null){
                isr = new BufferedReader(new InputStreamReader(ins));
                char[] charBuffer = new char[128];
                int readCount = 0;
                while((readCount = isr.read(charBuffer)) != -1){
                    sb.append(charBuffer,0,readCount);
                }
            }else{
                sb.append("");
            }
        }catch (IOException e){
            throw e;
        }finally {
            if(isr != null) {
                isr.close();
            }
        }
 
        sb.toString();
        body = sb.toString();
    }
 
    @Override
    public BufferedReader getReader() throws IOException {
        return new BufferedReader(new InputStreamReader(this.getInputStream()));
    }
 
    @Override
    public ServletInputStream getInputStream() throws IOException {
        final ByteArrayInputStream byteArrayIns = new ByteArrayInputStream(body.getBytes());
        ServletInputStream servletIns = new ServletInputStream() {
            @Override
            public boolean isFinished() {
                return false;
            }
 
            @Override
            public boolean isReady() {
                return false;
            }
 
            @Override
            public void setReadListener(ReadListener readListener) {
 
            }
 
            @Override
            public int read() throws IOException {
                return byteArrayIns.read();
            }
        };
        return  servletIns;
    }
}
import org.springframework.stereotype.Component; 
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
 
@Component
@WebFilter(filterName = "crownFilter", urlPatterns = "/*")
public class BodyReaderRequestFilter implements Filter {
    @Override
    public void init(FilterConfig filterConfig) throws ServletException { 
    }
 
    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest)req;
        HttpServletResponse response = (HttpServletResponse)res;
        BodyReaderRequestWrapper requestWrapper  = new BodyReaderRequestWrapper(request);
        if(requestWrapper == null){
            filterChain.doFilter(request,response);
        }else {
            filterChain.doFilter(requestWrapper,response);
        }
    }
 
    @Override
    public void destroy() { 
    }
}

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