先定义实体类:
package com.zf.vo; import java.sql.Timestamp; import 
com.fasterxml.jackson.annotation.JsonIgnore; import 
com.fasterxml.jackson.databind.annotation.JsonSerialize; import 
com.zf.control.JsonTimestampFormater; public class Person { private String name 
; @JsonIgnore //表示将该对象转换为json String的时候,忽略该属性 private int age ; 
@JsonSerialize(using = JsonTimestampFormater.class) 
//表示将该对象转换为Json对象的时候,使用的类型转器为自己定义的转换器 private Timestamp birthday ; public 
String getName() { return name; } public void setName(String name) { this.name 
= name; } public int getAge() { return age; } public void setAge(int age) { 
this.age = age; } public Timestamp getBirthday() { return birthday; } public 
void setBirthday(Timestamp birthday) { this.birthday = birthday; } }
类型转换器定义如下:
package com.zf.control; import java.io.IOException; import java.sql.Timestamp; 
import java.text.SimpleDateFormat; import 
com.fasterxml.jackson.core.JsonGenerator; import 
com.fasterxml.jackson.core.JsonProcessingException; import 
com.fasterxml.jackson.databind.JsonSerializer; import 
com.fasterxml.jackson.databind.SerializerProvider; public class 
JsonTimestampFormater extends JsonSerializer<Timestamp> { private final 
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); @Override 
public void serialize(Timestamp value, JsonGenerator jgen, SerializerProvider 
sp) throws IOException, JsonProcessingException { 
jgen.writeString(sdf.format(value)); } }
测试类如下:
package com.zf.test; import java.io.IOException; import java.sql.Timestamp; 
import com.fasterxml.jackson.core.JsonGenerationException; import 
com.fasterxml.jackson.databind.JsonMappingException; import 
com.fasterxml.jackson.databind.ObjectMapper; import com.zf.vo.Person; public 
class Test { public static void main(String[] args) throws 
JsonGenerationException, JsonMappingException, IOException { Person person = 
new Person(); person.setAge(19); person.setName("xxxxx"); 
person.setBirthday(new Timestamp(System.currentTimeMillis())); ObjectMapper 
mapper = new ObjectMapper(); String jsonstr = 
mapper.writeValueAsString(person); System.out.println(jsonstr); } }
打印结果
{"name":"xxxxx","birthday":"2012-08-03 03:05:06"}