按条件模糊查询及分页查询
1、查询助手
1 package cn.buaa.core.util;
2
3 import java.util.ArrayList;
4 import java.util.List;
5
6
7 public class QueryHelper {
8
9 //from子句
10 private String fromClause = "";
11 //where子句
12 private String whereClause = "";
13 //orderBy子句
14 private String orderByClause = "";
15
16 private List<Object> parameters;
17
18 //排序常量
19 public static String ORDER_BY_DESC = "DESC"; //降序
20 public static String ORDER_BY_ASC = "ASC"; //升序
21 /**
22 * 构造from子句(有别名)
23 * @param clazz 实体类
24 * @param alias 实体类对应的别名
25 */
26 public QueryHelper(Class clazz,String alias){
27 fromClause = "From " + clazz.getSimpleName() + " " +alias ;
28 System.out.println(fromClause);
29 }
30 /** 31 * 构造from子句（无别名）
32 * @param clazz 实体类
33 */
34 public QueryHelper(Class clazz){
35 fromClause = "From " + clazz.getSimpleName() ;
36 }
37
38 /**
39 * 构造where子句
40 * @param condition 查询条件语句：例如：i.title like ?
41 * @param params 查询条件语句中？对应的查询条件的值： 例如：%标题%
42 */
43 public void addCondition(String condition , Object... params ){
44 if(whereClause.length()>1){//非第一个查询条件
45 whereClause += " AND " + condition;
46 }else{//第一个查询条件
47 whereClause += " WHERE " + condition;
48 }
49
50 //设置查询条件值到查询条件集合中
51 if(parameters == null){
52 parameters = new ArrayList<Object>();
53 }
54 if(params != null){
55 for(Object param : params){
56 parameters.add(param);
57 }
58 }
59
60 }
61
62 /**
63 * 构造order by子句
64 * @param property 排序属性：如：i.createTime
65 * @param order 排序顺序，如：DESC 或 ASC
66 */
67 public void addOrderByProperty(String property,String order){
68 if(orderByClause.length()>1){//非第一个排序属性
69 orderByClause += " ," + property + " " + order;
70 }else{//第一个排序属性
71 orderByClause += " ORDER BY " + property + " " + order;
72 }
73 }
74 //查询hql语句
75 public String getQueryListHql(){
76
77 return fromClause + whereClause + orderByClause ;
78 }
79
80 //查询统计数的hql语句
81 public String getQueryCountHql(){
82
83 return "SELECT COUNT( * ) " + fromClause + whereClause;
84 }
85
86 //查询hql语句中？对应的查询条件值集合
87 public List<Object> getParameters(){
88
89 return parameters;
90 }
91 }
2、dao逻辑处理代码
@Override
public PageResult getPageResult(QueryHelper queryHelper, int pageNo, int pageSize) {
Query query = getSession().createQuery(queryHelper.getQueryListHql());
List<Object> parameters = queryHelper.getParameters();
if(parameters != null){
for(int i= 0;i<parameters.size();i++){
query.setParameter(i, parameters.get(i));
}
}
if(pageNo<1) pageNo =1;
query.setFirstResult((pageNo-1)*pageSize);
query.setMaxResults(pageSize);
List items = query.list();
//获取总记录数
Query queryCount = getSession().createQuery(queryHelper.getQueryCountHql());
if(parameters != null){
for(int i= 0;i<parameters.size();i++){
queryCount.setParameter(i, parameters.get(i));
}
}
long totalCount = (long) queryCount.uniqueResult();
return new PageResult(totalCount, pageNo, pageSize, items);
}
3、action调用处理代码
1 protected PageResult pageResult;
2 private int pageNo;
3 private int pageSize;
4 。。。。 5
6 // 列表页面
7 public String listUI() throws Exception {
8 // 加载分类集合
9 ActionContext.getContext().getContextMap().put("infoTypeMap", Info.INFO_TYPE_MAP);
10 QueryHelper queryHelper = new QueryHelper(Info.class,"i");
11 try {
12 if(info != null){
13 if(StringUtils.isNotBlank(info.getTitle())){
14 //搜索框乱码问题解决
15 info.setTitle(URLDecoder.decode(info.getTitle(),"utf-8"));
16 queryHelper.addCondition("i.title like ? ", "%" + info.getTitle() + "%");
17 }
18 queryHelper.addCondition("i.state = ?", "1");
19 }
20 //根据创建时间降序排序
21 queryHelper.addOrderByProperty(" i.createTime ", QueryHelper.ORDER_BY_DESC); 22 //infoList = infoService.findObjects(queryHelper);
23 pageResult = infoService.getPageResult(queryHelper,getPageNo(),getPageSize());
24 } catch (Exception e) {
25 throw new ActionException("action出现异常：" + e.getMessage());
26 }
27 return "listUI";
28 }
4、struts配置文件
<?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>
<package name="info-action" namespace="/nsfw" extends="base-default">
<action name="info_*" class="cn.buaa.nsfw.info.action.InfoAction"
method="{1}">
<result name="{1}">/WEB-INF/jsp/nsfw/info/{1}.jsp</result>
<result name="list" type="redirectAction">
<param name="actionName">info_listUI</param>
<!-- 搜索框搜索值回显 -->
<param name="info.title">${strTitle}</param>
<param name="pageNo">${pageNo}</param>
<!-- 解决搜索框框乱码 -->
<param name="encode">true</param>
</result>
</action>
</package>
</struts>
5、jsp显示页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<%@include file="/common/header.jsp"%> <title>信息发布管理</title>
<script type="text/javascript">
//全选、全反选
function doSelectAll() {
// jquery 1.6 前
//$("input[name=selectedRow]").attr("checked", $("#selAll").is(":checked"));
//prop jquery 1.6+建议使用
$("input[name=selectedRow]").prop("checked", $("#selAll").is(":checked"));
}
//添加
function doAdd(){
document.forms[0].action="${basePath}nsfw/info_addUI.action";
document.forms[0].submit();
}
//编辑
function doEdit(id){
document.forms[0].action="${basePath}nsfw/info_editUI.action?info.infoId=" + id;
document.forms[0].submit();
}
//删除
function doDelete(id){
document.forms[0].action="${basePath}nsfw/info_delete.action?info.infoId=" + id;
document.forms[0].submit();
}
//多选删除
function doDeleteAll(){
document.forms[0].action="${basePath}nsfw/info_deleteSelected.action";
document.forms[0].submit();
}
//异步发布信息，信息的id及将要改成的信息状态
function doPublic(infoId,state){
//1、更新信息状态
$.ajax({
url:"${basePath}nsfw/info_publicInfo.action",
data:{"info.infoId":infoId,"info.state":state},
type:"post",
success:function(msg){
//2、更新状态栏，操作栏的显示值
if("更新状态成功" msg){
if(state 1){//说明信息状态已被改成发布，状态栏显示发布，操作栏显示停用
$("#show_"+infoId).html("发布");
$("#oper_"+infoId).html('<a href="javascript:doPublic(''+infoId+'',0)">停用</a>');
}else{
$("#show_"+infoId).html("停用");
$("#oper_"+infoId).html('<a href="javascript:doPublic(''+infoId+'',1)">发布</a>');
}
}else{
alert("更新信息状态失败！");
}
},
error:function(){
alert("更新信息状态失败！");
}
});
}var list_url = "${basePath}nsfw/info_listUI.action";
function doSearch(){
//重置页号
$("#pageNo").val(1);
document.forms[0].action= list_url ;
document.forms[0].submit();
}
</script>
</head>
<body class="rightBody">
<form name="form1" action="" method="post">
<div class="p_d_1">
<div class="p_d_1_1">
<div class="content_info">
<div class="c_crumbs"><div><b></b><strong>信息发布管理</strong></div> </div>
<div class="search_art">
<li>
信息标题：<s:textfield name="info.title" cssClass="s_text" id="infoTitle" cssStyle="width:160px;"/>
</li>
<li><input type="button" class="s_button" value="搜 索" onclick="doSearch()"/></li>
<li style="float:right;">
<input type="button" value="新增" class="s_button" onclick="doAdd()"/>
<input type="button" value="删除" class="s_button" onclick="doDeleteAll()"/>
</li>
</div><div class="t_list" style="margin:0px; border:0px none;">
<table width="100%" border="0">
<tr class="t_tit">
<td width="30" align="center"><input type="checkbox" id="selAll" onclick="doSelectAll()" /></td>
<td align="center">信息标题</td>
<td width="120" align="center">信息分类</td>
<td width="120" align="center">创建人</td>
<td width="140" align="center">创建时间</td>
<td width="80" align="center">状态</td>
<td width="120" align="center">操作</td>
</tr>
<s:iterator value="pageResult.items" status="st">
<tr <s:if test="#st.odd"> bgcolor="f8f8f8" </s:if> >
<td align="center"><input type="checkbox" name="selectedRow" value="<s:property value='infoId'/>"/></td>
<td align="center"><s:property value="title"/></td>
<td align="center">
<s:property value="#infoTypeMap[type]"/>
</td>
<td align="center"><s:property value="creator"/></td>
<td align="center"><s:date name="createTime" format="yyyy-MM-dd HH:mm"/></td>
<td id="show_<s:property value='infoId'/>" align="center"><s:property value="state1?'发布':'停用'"/></td>
<td align="center">
<span id="oper_<s:property value='infoId'/>">
<s:if test="state1">
<a href="javascript:doPublic('<s:property value='infoId'/>',0)">停用</a>
</s:if>
<s:else>
<a href="javascript:doPublic('<s:property value='infoId'/>',1)">发布</a>
</s:else></span>
<a href="javascript:doEdit('<s:property value='infoId'/>')">编辑</a>
<a href="javascript:doDelete('<s:property value='infoId'/>')">删除</a>
</td>
</tr>
</s:iterator>
</table>
</div>
</div>
<jsp:include page="/common/pageNavigator.jsp"/>
</div>
</form></body>
</html>
6、分页代码jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<div class="c_pate" style="margin-top: 5px;">
<s:if test="pageResult.totalCount > 0"> <table width="100%" class="pageDown" border="0" cellspacing="0" cellpadding="0">
<tr>
<td align="right"> 总共<s:property value="pageResult.totalCount"/><条记录，当前第<s:property value="pageResult.pageNo"/>页， 共 <s:property value="pageResult.totalPageCount"/> 页 <s:if test="pageResult.pageNo > 1">
<a href="javascript:doGoPage(<s:property value="pageResult.pageNo-1"/>)">上一页</a>
</s:if>
<s:if test="pageResult.pageNo < pageResult.totalPageCount"> <a href="javascript:doGoPage(<s:property value="pageResult.pageNo+1"/>)">下一页</a>
</s:if> 到 <input id="pageNo" name="pageNo" type="text" style="width: 30px;" onkeypress="if(event.keyCode == 13){doGoPage(this.value);}" min="1" max="" value="<s:property value="pageResult.pageNo"/>" />
</td>
</tr>
</table>
</s:if><s:else> 暂无数据！ </s:else>
</div>
<script type="text/javascript"> //翻页
function doGoPage(pageNo){
document.getElementById("pageNo").value = pageNo; document.forms[0].action =list_url;
document.forms[0].submit();
}
</script>
</div>
7、特别注意搜索框的回显问题以及会先后乱码的处理，还有struts配置文件的传值问题
浙公网安备 33010602011771号