新人求助，关于JsonConfig过滤JavBean set集合 配置问题

[qq_24142261]

public class CrmCustomer implements java.io.Serializable {
	private Integer id;
	private CrmCustomerArea crmCustomerArea
	private String Name;

set/get.......

public class CrmCustomerArea implements java.io.Serializable {
	private Integer id;
	private String area;
	private Set<CrmCustomer> crmCustomers = new HashSet<CrmCustomer>(0);

set/get.......
}

private CrmCustomer cust = new CrmCustomer();
	
public void findCust(){	
		try {
			HttpServletResponse response = ServletActionContext.getResponse();
			response.setContentType("application/json;charset=utf-8");
			PrintWriter out = response.getWriter();			
            JsonConfig cfg = new JsonConfig();
			cfg.setExcludes(new String[]{"????"});
			out.print(JSONObject.fromObject(cust,cfg));
			out.flush();		
			out.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

请问怎样写过滤才能过滤掉crmCustomerArea的Set集合而保留其他属性