續上篇，改用struts2實現JQuery的ajax異步請求

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前面的兩篇因爲是在csdn文本上編寫的，可能出現很多錯誤，這次在markdown上編寫，應該錯誤會少很多，然後這次ajax請求也從上一次簡單的入門$.post方法換成了$.ajax方法，剩下改動就是刪除了servlet文件，加入struts2框架
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1.導包（包括上一次GSON、Hibernate的包）

2.編寫我們的action類，可以把上一次的servlet刪了，創建一個新的類->繼承ActionSupport類->組合鍵shift+alt+s->選擇Override/Implement Methods ->找到execute方法->確定。

import java.util.List;

import org.apache.struts2.ServletActionContext;

import com.google.gson.Gson;
import com.opensymphony.xwork2.ActionSupport;

import xxx.xxx.xxx.service.StrutsSearchService;

public class AjaxStruts2Hibernate extends ActionSupport{
    private StrutsSearchService ss = new StrutsSearchService();
    // 1.使用屬性驅動獲得頁面傳來的參數，要爲屬性創建getter和setter方法
    private String content;
    public String getContent() {
        return content;
    }
    public void setContent(String content) {
        this.content = content;
    }
    @Override
    public String execute() throws Exception {
        System.out.println(content);
        // 2.調用service方法進行模糊查詢
        List<String> list = ss.SearchHname(content);
        System.out.println("action:"+list);
        // 3.將接受結果list轉化成json格式的字符串返回
        Gson gson = new Gson();
        String json = gson.toJson(list);
        // 4.把json字符串返回到index.jsp頁面
        ServletActionContext.getResponse().getWriter().write(json);
        //這裏因爲不需要跳轉到新頁面，返回null
        return null;
    }

}

3.在src下新建我們的struts.xml文件，然後配置

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">
    <struts>
        <!-- 這個是國際化編碼，處理亂碼的，我們開發可以不寫 -->
        <constant name="struts.i18n.encoding" value="UTF-8"></constant>
        <!-- 這裏是開發者模式，可以支持reload，即我們改寫代碼不用重啓服務器就可以重新編譯 -->
        <constant name="struts.devMode" value="true"></constant>
        <!-- name隨便取，namespace是我們訪問action的命名空間，extends必須繼承struts-default，否則無法享用struts2功能 -->
        <package name="demo" namespace="/" extends="struts-default">
        <!-- 這裏是配置action的，name就是我們後面用於訪問路徑的名字，class填寫action完整類名，method是指定將引用該類下的哪個方法 -->
            <action name="AjaxStruts2Hibernate" class="xxx.xxx.xxx.action.AjaxStruts2Hibernate" method="execute">
                <!-- 如果在action類中return "success"，那麼將轉發到/inde.jsp中，
                還可以加入type屬性，指定redirect重定向，指定chain轉發到action，
                指定redirectAction重定向到action等
                 -->
                <result name="success">/index.jsp</result>
                <!-- <result name="error" type="redirectAction">
                    <param name="actionName">errorAction</param>
                    <param name="namespace">/error</param>
                </result> -->
            </action>
        </package>

    </struts>

4.在web.xml中加入sturts2核心過濾器

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
  <display-name>ajax_backstage3</display-name>
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    <welcome-file>default.html</welcome-file>
    <welcome-file>default.htm</welcome-file>
    <welcome-file>default.jsp</welcome-file>
  </welcome-file-list>
  <filter>
    <filter-name>struts2</filter-name>
    <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
  </filter>
  <filter-mapping>
    <filter-name>struts2</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
 </web-app>

5.大功告成，剩下只用把上一次的service類該一下名字就行了
service類：

import java.util.List;

import org.hibernate.Session;
import org.hibernate.Transaction;

import xxx.xxx.xxx.dao.SearchHibernateDao;
import xxx.xxx.xxx.utils.HibernateUtils;

public class StrutsSearchService {

    public List<String> SearchHname(String content) {
        // 管理事務
        Session session = HibernateUtils.getCurrentSession();
        Transaction tx = session.beginTransaction();
        //調用dao層查詢方法
        SearchHibernateDao ssd = new SearchHibernateDao();
        List<String> list = ssd.searchHname(content);
        System.out.println("service"+list);
        tx.commit();
        return list;
    }

}

dao類：

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import xxx.xxx.xxx.utils.DataBase;

public class SearchDao extends DataBase {

    public List<String> search(String content) throws SQLException {
        // TODO Auto-generated method stub
        List<String> list = new ArrayList<String>();
        String sql = "select * from cst_linkman where lkm_name like '%"+content+"%'" ;
        rs = commonQuery(sql);
        while(rs.next()){
            list.add(rs.getString("lkm_name"));
        }
        return list;
    }

}

HibernateUtils：

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;


public class HibernateUtils {
    private static SessionFactory sf;
    static{
        Configuration conf = new Configuration().configure();
        sf = conf.buildSessionFactory();
    }

    public static Session getOpenSession(){

        Session session = sf.openSession();
        return session;
    }
    public static Session getCurrentSession(){
        Session session = sf.getCurrentSession();
        return session;
    }
}

index.jsp：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
<script type="text/javascript" src="JS/jquery-1.11.0.js"></script>
<script type="text/javascript">
//爲搜索綁定聚焦事件
$(function(){
    $("#search").keyup(function(){
        var content = $(this).val();
        var returnStr = "";
        $.ajax({
            type:"POST",
            url:"/ajax_backstage4/AjaxStruts2Hibernate",
            contentType:"application/x-www-form-urlencoded",
            data:{"content":content},
            dataType:"json",
            success:function(data){
                //請求正確後的操作
                if(data.length>0){
                    for(var i=0;i<data.length;i++){
                        returnStr += "<div id='div' style='padding:5px;cursor:pointer' onmouseover='overFn(this)' onmouseout='outFn(this)' onclick='clickFn(this)'>"+data[i]+"</div>";//
                    } 
                    $("#div").html(returnStr);
                    $("#div").css("display","block");
                }else{
                    $("#div").css("display","none");
                }
            },
            error:function(result){
                //請求失敗後的操作
            }
        }); 
    });
    $("#search").blur(function(){
        $("#div").css("display","none");
    });
})
//綁定按鈕事件
$(function(){
    $("#button").click(function(){
        var sub = $("#search").val();
        $.ajax({
            type:"POST",
            url:"/ajax_backstage4/AjaxStruts2Hibernate",
            contentType:"application/json",
            data:JSON.stringify({"sub":sub}),
            dataType:"json",
            success:function(result){
                //請求正確後的操作
            },
            error:function(result){
                //請求失敗後的操作
            }
        });
    });
})
//對div添加鼠標移入效果
function overFn(obj){
    $(obj).css("background-color","yellow");
}

//對div添加鼠標移出效果
function outFn(obj){
    $(obj).css("background-color","#F0F8FF");
}

//對div內容添加點擊效果
function clickFn(obj){
    $("#search").val($(obj).html());
    $("#div").css("display","none");
}


</script>
<body>  
    <input type="text" id="search" /><input type="button" id="button" value="按鈕">
    <div id="div" style="width:150px;display:none;background-color: #F0F8FF"></div>
    <s:debug></s:debug>
</body>
</html>