Json-lib-2.4-jdk15.jar error Net.sf.json.JSONException:There is a cycle in the hierarchy! solution (Hibernate)

This problem is easy to use with Hibernate, mainly due to the cascading relationship of Pojo class attributes. For example, employees and departments, which have departmental attributes in the employee table, and a collection of employees in the departmental table, will throw this exception if there is a problem with nested references.

The workaround is simple, when you convert each object to a JSON object, use the Setexcludes function to remove the cascading properties, as follows:

For example, Cityvo has associated properties Provincevo province and region attributes Set<districtvo> Districtlist

Using hibernate to query all city will correlate province and ....

Jsonconfig config = new Jsonconfig ();

Config.setexclude (New string[]{"Province", districtlist});

Jsonarray.fromjsonarray (Citylist,config);

OK, fix it.

Json-lib-2.4-jdk15.jar error Net.sf.json.JSONException:There is a cycle in the hierarchy! solution (Hibernate)