var xmlHttp; 
 
  function doti(x){
      getXmlHttpRequestObject();
      var url="showValue_selectValue.action?key="+x;
      xmlHttp.open("GET",url,true);
      xmlHttp.onreadystatechange=callback;
      xmlHttp.send(null);
 }
 
 function getXmlHttpRequestObject() { 
        if (window.XMLHttpRequest) { 
            xmlHttp= new XMLHttpRequest(); 
        } else { 
            if (window.ActiveXObject) { 
                  xmlHttp= new ActiveXObject("Microsoft.XMLHTTP"); 
            } else { 
                alert("您的浏览器不支持"); 
            } 
        } 
    } 
  function callback(){
      if(xmlHttp.readyState==4){
          if(xmlHttp.status==200){
             createTextValue();
          }
      }
  }
  
  function createTextValue(){
      var str=xmlHttp.responseText;
           alert(str);
    }
 

   package com.action;

import java.util.List;

import com.dao.DaoImpl;
import com.opensymphony.xwork2.ActionSupport;

public class ShowValueAction extends ActionSupport{

    
    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private String key;
    private String list;
    private DaoImpl di;
    
    public String getList() {
        return list;
    }

    public void setList(String list) {
        this.list = list;
    }

    public String getKey() {
        return key;
    }

    public void setKey(String key) {
        this.key = key;
    }

    public String selectValue(){
        di=new DaoImpl();
       list=di.selectValue(key);
        return SUCCESS;
    }
}