Struts2+hibernate3+JQuery+ajax+json三级联动

package online.exam.action; import java.io.IOException; import java.util.List; import javax.servlet.http.HttpServletResponse; import org.apache.struts2.ServletActionContext; import online.exam.dao.CityServiceBean; import online.exam.dao.ProvinceServiceBean; import online.exam.dao.TownServiceBean; import online.exam.domain.City; import online.exam.domain.Province; //import online.exam.domain.Province; import online.exam.domain.Town; import net.sf.json.JSONArray; //import org.apache.struts2.ServletActionContext; import com.opensymphony.xwork2.ActionSupport; public class ListAction extends ActionSupport { private static final long serialVersionUID = -3433374530474555366L; private Integer pid; private Integer cid; private HttpServletResponse response=ServletActionContext.getResponse(); //获取省 public String getProvince(){ ProvinceServiceBean provinceBean=new ProvinceServiceBean(); List<Province> provinceList=provinceBean.getProvince(); JSONArray jsonArray=JSONArray.fromObject(provinceList); response.setContentType("text/html;charset=UTF-8"); try { response.getWriter().print(jsonArray.toString()); } catch (IOException e) { e.printStackTrace(); } return null; } //根据省获取市 public String getCity(){ CityServiceBean cityBean=new CityServiceBean(); List<City> cityList=cityBean.getCity(pid); JSONArray jsonArray=JSONArray.fromObject(cityList); response.setContentType("text/html;charset=UTF-8"); try { response.getWriter().print(jsonArray.toString()); } catch (IOException e) { e.printStackTrace(); } return null; } //根据市获取区县 public String getTown(){ TownServiceBean townDao=new TownServiceBean(); List<Town> townList=townDao.getTown(cid); JSONArray jsonArray=JSONArray.fromObject(townList); response.setContentType("text/html;charset=UTF-8"); try { response.getWriter().print(jsonArray.toString()); } catch (IOException e) { e.printStackTrace(); } return null; } //----------------- public Integer getPid() { return pid; } public void setPid(Integer pid) { this.pid = pid; } public Integer getCid() { return cid; } public void setCid(Integer cid) { this.cid = cid; } }