There is a cycle in the hierarchy!

发布网友发布时间：2022-05-17 00:06

共2个回答

懂视网时间：2022-05-17 04:27

解决办法

1.设置JSON-LIB让其过滤掉引起循环的字段。

Java代码
代码如下:
JsonConfig config = new JsonConfig();
config.setIgnoreDefaultExcludes(false);
config.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);
config.registerJsonValueProcessor(Date.class,new DateJsonValueProcessor("yyyy-MM-dd")); //date processor register
config.setExcludes(new String[]{//只要设置这个数组，指定过滤哪些字段。
"consignee",
"contract",
"coalInfo",
"coalType",
"startStation",
"balanceMan",
"endStation"
});
String tempStr = "{"TotalRecords":"+ total.toString() +","Datas":"+JSONSerializer.toJSON(list,config).toString()+"}";
out.print(tempStr);
JsonConfig config = new JsonConfig();
config.setIgnoreDefaultExcludes(false);
config.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);
config.registerJsonValueProcessor(Date.class,new DateJsonValueProcessor("yyyy-MM-dd")); //date processor register
config.setExcludes(new String[]{//只要设置这个数组，指定过滤哪些字段。 "consignee", "contract", "coalInfo", "coalType", "startStation", "balanceMan", "endStation" }); String tempStr = "{"TotalRecords":"+ total.toString() +","Datas":"+JSONSerializer.toJSON(list,config).toString()+"}"; out.print(tempStr);

2.设置JSON-LIB的setCycleDetectionStrategy属性让其自己处理循环，省事但是数据过于复杂的话会引起数据溢出或者效率低下。
Java代码
[code]
JsonConfig config = new JsonConfig();
config.setIgnoreDefaultExcludes(false);
config.setCycleDetectionStrategy(CycleDetectionStrategy.LENIENT);
config.registerJsonValueProcessor(Date.class,new DateJsonValueProcessor("yyyy-MM-dd")); //date processor register
String tempStr = "{"TotalRecords":"+ total.toString() +","Datas":"+JSONSerializer.toJSON(list,config).toString()+"}";
out.print(tempStr);

热心网友时间：2022-05-17 01:35

有把有关联的属性放到json数组中就可以了。因为Resource的json数组中有roles数组，而且roles的数组元素中又有Resource数组，死循环了。用JSONConfig把roles去除就可以了。