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;  
  
/** 
 *  java日期对象经过Jackson库转换成JSON日期格式化自定义类 
 * @author godfox 
 * @date 2010-5-3 
 */  
public class CustomDateSerializer extends JsonSerializer<Date> {  
  
        @Override  
        public void serialize(Date value, JsonGenerator jgen, SerializerProvider provider) throws IOException, JsonProcessingException {  
                SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");  
                String formattedDate = formatter.format(value);  
                jgen.writeString(formattedDate);  
        }  
}  

public static class CustomSerializer2 extends JsonSerializer<Region> {
		@Override
		public void serialize(Region region, JsonGenerator jgen, SerializerProvider provider) throws IOException,
				JsonProcessingException {
			Map<String, Object> data = Maps.newHashMap();
			data.put("id", region.getId());
			data.put("name", region.getName());
			// ... more
			jgen.writeObject(data);
		}
	}

@Entity  
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)  
@JsonAutoDetect  
/** 
* 在此标记不生成json对象的属性，这里我标记了两个属性一个hibernateLazyInitializer属性，为什么要标记这个 
* 属性参考前面的博文，一个password属性，出于安全这个当然不能转换成json对象了，毕竟json是在前台调用的， 
* 如果你想转换的时候忽略某个属性，可以在后面继续加上 
*/  
@JsonIgnoreProperties(value = {"hibernateLazyInitializer", "password"})  
public class User  
{  
    private Long id;  
    private String name;  
    private String password;  
    private String email;  
    private Date createAt;  
    @Id  
    @GeneratedValue(strategy = GenerationType.IDENTITY)  
    public Long getId() {  
        return id;  
    }  
  
    public void setId(Long id) {  
        this.id = id;  
    }  
    /** 
    * 转换日期对象的输出格式，CustomDateSerializer 代码参考前面的博文     
        */  
    @JsonSerialize(using = CustomDateSerializer.class)  
    public Date getCreateAt() {  
            return createAt;  
    }  
  
    public void setCreateAt(Date createAt) {  
            this.createAt = createAt;  
    } 

    @JsonSerialize(using = CustomSerializer2.class)
    public List<Region> getRegions() {  
            return this.regions;  
    } 
    /** 
    * 其他的getter和setter省略 
    */  
}