json list map 对象 转换成tostring Json的数据格式

package import com.alibaba.fastjson.JSON;import com.alibaba.fastjson.serializer.SerializerFeature;import import java.util.ArrayList;import java.util.Date;import java.util.HashMap;public class Dmeo {    public static void main(String [] str){        //数组        ArrayList list = new ArrayList();        list.add("11");        list.add("22");        System.out.println(list.toString());        System.out.println(JSON.toJSONString(list));        System.out.println("--------------");        //集合        HashMap<Object, Object> map = new HashMap<>();        map.put("11","aa");        map.put("22","bb");        System.out.println(map.toString());        System.out.println(JSON.toJSONString(map));        System.out.println("--------------");        //对象        BaseEntity base = new BaseEntity();        base.setId(1L);        base.setDateCreated(new Date());        base.setVersion(1);        System.out.println(base.toString());        System.out.println(JSON.toJSONString(base));        System.out.println(JSON.toJSONString(base.toString()));        System.out.println("--------------");        //        ArrayList list1 = new ArrayList();        list1.add(base);        list1.add(base);        System.out.println(list1.toString());        System.out.println(JSON.toJSONString(JSON.toJSONString(list1)));        System.out.println(JSON.toJSONString(list1,SerializerFeature.DisableCircularReferenceDetect));        System.out.println("--------------");    }}

[11, 22]["11","22"]--------------{11=aa, 22=bb}{"11":"aa","22":"bb"}--------------BaseEntity{id=1, remarks='null', recordStatus=null, version=1, dateCreated=Wed Dec 20 10:58:31 CST 2017, lastModified=null}{"dateCreated":1513738711117,"id":1,"version":1}"BaseEntity{id=1, remarks='null', recordStatus=null, version=1, dateCreated=Wed Dec 20 10:58:31 CST 2017, lastModified=null}"--------------[BaseEntity{id=1, remarks='null', recordStatus=null, version=1, dateCreated=Wed Dec 20 10:58:31 CST 2017, lastModified=null}, BaseEntity{id=1, remarks='null', recordStatus=null, version=1, dateCreated=Wed Dec 20 10:58:31 CST 2017, lastModified=null}]"[{\"dateCreated\":1513738711117,\"id\":1,\"version\":1},{\"$ref\":\"$[0]\"}]"[{"dateCreated":1513738711117,"id":1,"version":1},{"dateCreated":1513738711117,"id":1,"version":1}]--------------