SpringMVC日期转换之JsonSerialize

左手的ㄟ右手 2022-09-11 08:17 180阅读 0赞

在SPRING MVC3中，比如做REST时，经常要用JASON去解析，遇到了日期格式化的问题，  
请看例子：  
  
1） 比如有一个POJO  
  package com.loiane.model;  
  
import java.util.Date;  
  
import org.codehaus.jackson.annotate.JsonAutoDetect;  
  
@JsonAutoDetect  
@Entity  
public class Company \{   
  
    private int id;  
    private double price;  
    private String company;  
    private Date date;  
    private String size;  
    private byte visible;  
\}  
  
2）在controller中，返回一个MAP  
   public @ResponseBody Map<String,List<Company>> view() throws Exception  
  
3） 于是SPIRNG MVC返回如下的JSON字符：  
   \{"total":27,"data":\[\{"price":71.72,"company":"3m Co","visible":1,"id":1,"size":"large","date":1188615600000\},\{"price":29.01,"company":"Aloca  
Inc","visible":0,"id":2,"size":"medium","date":1185937200000\},\{"price":83.81,"company":"Altria Group  
Inc","visible":0,"id":3,"size":"large","date":1186110000000  
。。。。。。。。。。。。。。。。  
  
4） 可以看到，返回的时间格式不大好看  
  
5）于是，可以这样设置：  
   @JsonSerialize(using=JsonDateSerializer.class)  
public Date getDate() \{   
    return date;  
\}  
其中   JsonDateSerializer是新编写的类，继承了JsonSerializer  
  import java.io.IOException;  
import java.text.SimpleDateFormat;  
import java.util.Date;  
  
import org.codehaus.jackson.JsonGenerator;  
import org.codehaus.jackson.JsonProcessingException;  
import org.codehaus.jackson.map.JsonSerializer;  
import org.codehaus.jackson.map.SerializerProvider;  
import org.springframework.stereotype.Component;  
@Component  
public class JsonDateSerializer extends JsonSerializer<Date>\{   
  
    private static final SimpleDateFormat dateFormat = new SimpleDateFormat("MM-dd-yyyy");  
  
    @Override  
    public void serialize(Date date, JsonGenerator gen, SerializerProvider provider)  
            throws IOException, JsonProcessingException \{   
  
        String formattedDate = dateFormat.format(date);  
  
        gen.writeString(formattedDate);  
    \}  
  
\}  
  
   很简单，格式化一下，这下输出JSON就可以了  
\{"total":27,"data":\[\{"price":71.72,"company":"3m Co","visible":1,"id":1,"size":"large","date":"09-01-2007"\},\{"price":29.01,"company":"Aloca  
Inc","visible":0,"id":2,"size":"medium","date":"08-01-2007"\},\{"price":83.81,"company":"Altria Group  
Inc","visible":0,"id":3,"size":"large","date":"08-03-2007"\},\{"price":52.55,"company":"American Express Company","visible":1,"id":4,"size":"extra  
large","date":"01-04-2008"\},\{"price":64.13,"company":"American International Group  
Inc.","visible":1,"id":5,"size":"small","date":"03-04-2008"\},\{"price":31.61,"company":"AT&T Inc.","visible":0,"id":6,"size":"extra  
large","date":"02-01-2008"\},\{"price":75.43,"company":"Boeing Co.","visible":1,"id":7,"size":"large","date":"01-01-2008"\},\{"price":67.27,"company":"Caterpillar  
Inc.","visible":1,"id":8,"size":"medium","date":"12-03-2007"\},\{"price":49.37,"company":"Citigroup,  
Inc.","visible":1,"id":9,"size":"large","date":"11-24-2007"\},\{"price":40.48,"company":"E.I. du Pont de Nemours and Company","visible":0,"id":10,"size":"extra  
large","date":"05-09-2007"\}\],"success":true\}