一、概述

今天自己做了个项目练练,然后有一些分页的功能,自己把分页的功能做了一个简单的总结,然后,为了以后能够方便自己的开发,做了一个baseDao的实现。

二、代码实现

2.1、分页的实体类pageBean

package org.sihai.utils;

import java.util.List;

public class PageBean {
    //当前页数
    private Integer currentPage;
    //总记录数
    private Integer totalCount;
    //每页显示条数
    private Integer pageSize;
    //总页数
    private Integer totalPage;
    //分页列表数据
    private List    list;
    public PageBean(Integer currentPage, Integer totalCount, Integer pageSize) {
        this.totalCount = totalCount;

        this.pageSize =  pageSize;

        this.currentPage = currentPage;

        if(this.currentPage == null){
            //如页面没有指定显示那一页.显示第一页.
            this.currentPage = 1;
        }

        if(this.pageSize == null){
            //如果每页显示条数没有指定,默认每页显示3条
            this.pageSize = 3;
        }

        //计算总页数
        this.totalPage = (this.totalCount+this.pageSize-1)/this.pageSize;

        //判断当前页数是否超出范围
        //不能小于1
        if(this.currentPage < 1){
            this.currentPage = 1;
        }
        //不能大于总页数
        if(this.currentPage > this.totalPage){
            this.currentPage = this.totalPage;
        }

    }
    //计算起始索引
    public int getStart(){
        return (this.currentPage-1)*this.pageSize;
    }

    public Integer getCurrentPage() {
        return currentPage;
    }
    public void setCurrentPage(Integer currentPage) {
        this.currentPage = currentPage;
    }
    public Integer getTotalCount() {
        return totalCount;
    }
    public void setTotalCount(Integer totalCount) {
        this.totalCount = totalCount;
    }
    public Integer getPageSize() {
        return pageSize;
    }
    public void setPageSize(Integer pageSize) {
        this.pageSize = pageSize;
    }
    public Integer getTotalPage() {
        return totalPage;
    }
    public void setTotalPage(Integer totalPage) {
        this.totalPage = totalPage;
    }
    public List getList() {
        return list;
    }
    public void setList(List list) {
        this.list = list;
    }

}

2.2、Action的实现

package org.sihai.web.action;

import org.apache.commons.lang3.StringUtils;
import org.hibernate.criterion.DetachedCriteria;
import org.hibernate.criterion.Restrictions;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.ModelDriven;

import org.sihai.domain.user;
import org.sihai.domain.User;
import org.sihai.service.userService;
import org.sihai.service.UserService;
import org.sihai.utils.PageBean;

public class userAction extends ActionSupport implements ModelDriven<user> {
    private user user = new user();

    private userService cs;

    private Integer currentPage;
    private Integer pageSize;
    public String list() throws Exception {
        //封装离线查询对象
        DetachedCriteria dc = DetachedCriteria.forClass(user.class);
        //判断并封装参数
        if(StringUtils.isNotBlank(user.getuser_name())){
            dc.add(Restrictions.like("user_name", "%"+user.getuser_name()+"%"));
        }

        //1 调用Service查询分页数据(PageBean)
        PageBean pb = cs.getPageBean(dc,currentPage,pageSize);
        //2 将PageBean放入request域,转发到列表页面显示
        ActionContext.getContext().put("pageBean", pb);
        return "list";
    }

    @Override
    public user getModel() {
        return user;
    }

    public void setCs(userService cs) {
        this.cs = cs;
    }

    public Integer getCurrentPage() {
        return currentPage;
    }

    public void setCurrentPage(Integer currentPage) {
        this.currentPage = currentPage;
    }

    public Integer getPageSize() {
        return pageSize;
    }

    public void setPageSize(Integer pageSize) {
        this.pageSize = pageSize;
    }

}

2.3、service的实现

package org.sihai.service.impl;

import java.util.List;

import org.hibernate.criterion.DetachedCriteria;

import org.sihai.dao.userDao;
import org.sihai.domain.user;
import org.sihai.service.userService;
import org.sihai.utils.PageBean;

public class userServiceImpl implements userService {
    private userDao cd;
    @Override
    public PageBean getPageBean(DetachedCriteria dc, Integer currentPage, Integer pageSize) {
        //1 调用Dao查询总记录数
        Integer totalCount = cd.getTotalCount(dc);
        //2 创建PageBean对象
        PageBean pb = new PageBean(currentPage, totalCount, pageSize);
        //3 调用Dao查询分页列表数据

        List<user> list = cd.getPageList(dc,pb.getStart(),pb.getPageSize());
        //4 列表数据放入pageBean中.并返回
        pb.setList(list);
        return pb;
    }
    public void setCd(userDao cd) {
        this.cd = cd;
    }

}

2.4、baseDao的具体实现(通用基类)

package org.sihai.dao.impl;

import java.io.Serializable;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.List;

import org.hibernate.criterion.DetachedCriteria;
import org.hibernate.criterion.Projections;
import org.springframework.orm.hibernate5.support.HibernateDaoSupport;

import org.sihai.dao.BaseDao;
import org.sihai.domain.user;

public class BaseDaoImpl<T> extends HibernateDaoSupport implements BaseDao<T> {

    private Class clazz;//用于接收运行期泛型类型

    public BaseDaoImpl() {
        //获得当前类型的带有泛型类型的父类
        ParameterizedType ptClass = (ParameterizedType) this.getClass().getGenericSuperclass();
        //获得运行期的泛型类型
        clazz = (Class) ptClass.getActualTypeArguments()[0];
    }

    @Override
    public void save(T t) {
        getHibernateTemplate().save(t);
    }

    @Override
    public void delete(T t) {

        getHibernateTemplate().delete(t);

    }

    @Override
    public void delete(Serializable id) {
        T t = this.getById(id);//先取,再删
        getHibernateTemplate().delete(t);
    }

    @Override
    public void update(T t) {
        getHibernateTemplate().update(t);
    }

    @Override
    public T getById(Serializable id) {

        return (T) getHibernateTemplate().get(clazz, id);
    }

    @Override
    public Integer getTotalCount(DetachedCriteria dc) {
        //设置查询的聚合函数,总记录数
        dc.setProjection(Projections.rowCount());

        List<Long> list = (List<Long>) getHibernateTemplate().findByCriteria(dc);

        //清空之前设置的聚合函数
        dc.setProjection(null);

        if(list!=null && list.size()>0){
            Long count = list.get(0);
            return count.intValue();
        }else{
            return null;
        }

    }

    @Override
    public List<T> getPageList(DetachedCriteria dc, Integer start, Integer pageSize) {

        List<T> list = (List<T>) getHibernateTemplate().findByCriteria(dc, start, pageSize);

        return list;
    }

}

2.5、baseService的具体实现

package org.sihai.qualitycontrol.util.base;

import java.io.Serializable;
import java.util.List;

import org.springframework.transaction.annotation.Transactional;
@Transactional
public interface BaseEbi<T> {

    public void save(T t);

    public void update(T t);

    public void delete(T t);

    public List<T> getAll();

    public T get(Serializable uuid);

    public List<T> getAll(BaseQueryModel qm, Integer pageNum,Integer pageCount);

    public Integer getCount(BaseQueryModel qm);

}

2.6、baseAction的具体实现

package org.sihai.qualitycontrol.util.base;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.struts2.ServletActionContext;

import org.sihai.qualitycontrol.auth.emp.vo.EmpModel;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

public class BaseAction  extends ActionSupport{
    public static final String LIST = "list";
    public static final String TO_LIST = "toList";
    public static final String INPUT = "input";

    public Integer pageNum = 1;
    public Integer pageCount = 10;
    public Integer maxPageNum;
    public Integer dataTotal;

    public String getActionName(){
        //动态
        //DepAction ->dep
        //EmpAction ->emp
        String actionName = this.getClass().getSimpleName();
        //DepAction ->Dep
        String temp = actionName.substring(0, actionName.length()-6);
        //Dep ->dep     OrderDetailAction   ->orderDetail  orderdetail
        return temp.substring(0,1).toLowerCase()+temp.substring(1);
    }

    protected void setDataTotal(int dataTotal){
        this.dataTotal = dataTotal ;
        maxPageNum = (dataTotal + pageCount -1) / pageCount;
    }

    protected void put(String name,Object obj){
        ActionContext.getContext().put(name,obj);
    }

    protected Object get(String name){
        return ActionContext.getContext().get(name);
    }

    protected void putSession(String name,Object obj){
        ActionContext.getContext().getSession().put(name,obj);
    }

    protected Object getSession(String name){
        return ActionContext.getContext().getSession().get(name);
    }

    protected EmpModel getLogin(){
        return (EmpModel) getSession(EmpModel.EMP_LOGIN_USER_OBJECT_NAME);
    }

    protected HttpServletRequest getRequest(){
        return ServletActionContext.getRequest();
    }

    protected HttpServletResponse getResponse(){
        return ServletActionContext.getResponse();
    }

}

2.7、页面的实现

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ taglib  prefix="s" uri="/struts-tags" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<TITLE>客户列表</TITLE> 
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<LINK href="${pageContext.request.contextPath }/css/Style.css" type=text/css rel=stylesheet>
<LINK href="${pageContext.request.contextPath }/css/Manage.css" type=text/css
    rel=stylesheet>
<script type="text/javascript" src="${pageContext.request.contextPath }/js/jquery-1.4.4.min.js"></script>
<SCRIPT language=javascript>
    function changePage(pageNum){
            //1 将页码的值放入对应表单隐藏域中
                $("#currentPageInput").val(pageNum);
            //2 提交表单
                $("#pageForm").submit();
    };

    function changePageSize(pageSize){
            //1 将页码的值放入对应表单隐藏域中
            $("#pageSizeInput").val(pageSize);
        //2 提交表单
            $("#pageForm").submit();
    };
</SCRIPT>

<META content="MSHTML 6.00.2900.3492" name=GENERATOR>
</HEAD>
<BODY>

        <TABLE cellSpacing=0 cellPadding=0 width="98%" border=0>
            <TBODY>
                <TR>
                    <TD width=15><IMG src="${pageContext.request.contextPath }/images/new_019.jpg"
                        border=0></TD>
                    <TD width="100%" background="${pageContext.request.contextPath }/images/new_020.jpg"
                        height=20></TD>
                    <TD width=15><IMG src="${pageContext.request.contextPath }/images/new_021.jpg"
                        border=0></TD>
                </TR>
            </TBODY>
        </TABLE>
        <TABLE cellSpacing=0 cellPadding=0 width="98%" border=0>
            <TBODY>
                <TR>
                    <TD width=15 background=${pageContext.request.contextPath }/images/new_022.jpg><IMG
                        src="${pageContext.request.contextPath }/images/new_022.jpg" border=0></TD>
                    <TD vAlign=top width="100%" bgColor=#ffffff>
                        <TABLE cellSpacing=0 cellPadding=5 width="100%" border=0>
                            <TR>
                                <TD class=manageHead>当前位置:客户管理 > 客户列表</TD>
                            </TR>
                            <TR>
                                <TD height=2></TD>
                            </TR>
                        </TABLE>
                        <TABLE borderColor=#cccccc cellSpacing=0 cellPadding=0
                            width="100%" align=center border=0>
                            <TBODY>
                                <TR>
                                    <TD height=25>
                                    <FORM id="pageForm" name="userForm"
                                        action="${pageContext.request.contextPath }/userAction_list"
                                        method=post>
                                        <!-- 隐藏域.当前页码 -->
                                        <input type="hidden" name="currentPage" id="currentPageInput" value="<s:property value="#pageBean.currentPage" />" />
                                        <!-- 隐藏域.每页显示条数 -->
                                        <input type="hidden" name="pageSize" id="pageSizeInput"       value="<s:property value="#pageBean.pageSize" />" />
                                        <TABLE cellSpacing=0 cellPadding=2 border=0>
                                            <TBODY>
                                                <TR>
                                                    <TD>客户名称:</TD>
                                                    <TD><INPUT class=textbox id=sChannel2
                                                        style="WIDTH: 80px" maxLength=50 name="user_name" value="${param.user_name}"></TD>

                                                    <TD><INPUT class=button id=sButton2 type=submit
                                                        value=" 筛选 " name=sButton2></TD>
                                                </TR>
                                            </TBODY>
                                        </TABLE>
                                    </FORM>
                                    </TD>
                                </TR>

                                <TR>
                                    <TD>
                                        <TABLE id=grid
                                            style="BORDER-TOP-WIDTH: 0px; FONT-WEIGHT: normal; BORDER-LEFT-WIDTH: 0px; BORDER-LEFT-COLOR: #cccccc; BORDER-BOTTOM-WIDTH: 0px; BORDER-BOTTOM-COLOR: #cccccc; WIDTH: 100%; BORDER-TOP-COLOR: #cccccc; FONT-STYLE: normal; BACKGROUND-COLOR: #cccccc; BORDER-RIGHT-WIDTH: 0px; TEXT-DECORATION: none; BORDER-RIGHT-COLOR: #cccccc"
                                            cellSpacing=1 cellPadding=2 rules=all border=0>
                                            <TBODY>
                                                <TR
                                                    style="FONT-WEIGHT: bold; FONT-STYLE: normal; BACKGROUND-COLOR: #eeeeee; TEXT-DECORATION: none">
                                                    <TD>客户名称</TD>
                                                    <TD>客户级别</TD>
                                                    <TD>客户来源</TD>
                                                    <TD>联系人</TD>
                                                    <TD>电话</TD>
                                                    <TD>手机</TD>
                                                    <TD>操作</TD>
                                                </TR>
                                                <s:iterator value="#pageBean.list" var="user" >
                                                <TR         
                                                    style="FONT-WEIGHT: normal; FONT-STYLE: normal; BACKGROUND-COLOR: white; TEXT-DECORATION: none">
                                                    <TD>
                                                        <s:property value="#user.user_name" />
                                                    </TD>
                                                    <TD>
                                                    <s:property value="#user.user_level" />
                                                    </TD>
                                                    <TD>
                                                    <s:property value="#user.user_source" />
                                                    </TD>
                                                    <TD>
                                                    <s:property value="#user.user_goods" />
                                                    </TD>
                                                    <TD>
                                                    <s:property value="#user.user_phone" />
                                                    </TD>
                                                    <TD>
                                                    <s:property value="#user.user_mobile" />
                                                    </TD>
                                                    <TD>
                                                    <a href="${pageContext.request.contextPath }/userServlet?method=edit&userId=${user.user_id}">修改</a>
                                                      
                                                    <a href="${pageContext.request.contextPath }/userServlet?method=delete&userId=${user.user_id}">删除</a>
                                                    </TD>
                                                </TR>
                                                </s:iterator>

                                            </TBODY>
                                        </TABLE>
                                    </TD>
                                </TR>

                                <TR>
                                    <TD><SPAN id=pagelink>
                                            <DIV
                                                style="LINE-HEIGHT: 20px; HEIGHT: 20px; TEXT-ALIGN: right">
                                                共[<B><s:property value="#pageBean.totalCount" /> </B>]条记录,[<B><s:property value="#pageBean.totalPage" /></B>]页
                                                ,每页显示 <%-- changePageSize($('#pageSizeSelect option').filter(':selected').val()) --%> 
                                                <select name="pageSize" onchange="changePageSize($('#pageSizeSelect option:selected').val())" id="pageSizeSelect" >
                                                    <option value="3" <s:property value="#pageBean.pageSize==3?'selected':''" /> >3</option>
                                                    <option value="5" <s:property value="#pageBean.pageSize==5?'selected':''" /> >5</option>
                                                </select>
                                                条
                                                [<A href="javaScript:void(0)" onclick="changePage(<s:property value='#pageBean.currentPage-1' />)" >前一页</A>]
                                                <B><s:property value="#pageBean.currentPage" /></B>
                                                [<A href="javaScript:void(0)" onclick="changePage(<s:property value='#pageBean.currentPage+1' />)"  >后一页</A>] 
                                                到
                                                <input type="text" size="3" id="page" name="page" value="<s:property value="#pageBean.currentPage" />"  />
                                                页

                                                <input type="button" value="Go" onclick="changePage($('#page').val())"/>
                                            </DIV>
                                    </SPAN></TD>
                                </TR>
                            </TBODY>
                        </TABLE>
                    </TD>
                    <TD width=15 background="${pageContext.request.contextPath }/images/new_023.jpg"><IMG
                        src="${pageContext.request.contextPath }/images/new_023.jpg" border=0></TD>
                </TR>
            </TBODY>
        </TABLE>
        <TABLE cellSpacing=0 cellPadding=0 width="98%" border=0>
            <TBODY>
                <TR>
                    <TD width=15><IMG src="${pageContext.request.contextPath }/images/new_024.jpg"
                        border=0></TD>
                    <TD align=middle width="100%"
                        background="${pageContext.request.contextPath }/images/new_025.jpg" height=15></TD>
                    <TD width=15><IMG src="${pageContext.request.contextPath }/images/new_026.jpg"
                        border=0></TD>
                </TR>
            </TBODY>
        </TABLE>

</BODY>
</HTML>

三、通用分页实现

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@taglib prefix="s" uri="/struts-tags"%>
<table width="100%" border="0" cellpadding="0" cellspacing="0">
    <tr>
        <td width="51%"> </td>
        <td width="13%">共${dataTotal}条记录
        <td width="6%">
            <a id="fir" class="sye">首  页</a>
        </td>
        <td width="6%">
            <a id="pre" class="sye">上一页</a>
        </td>
        <td width="6%">
            <a id="next" class="sye">下一页</a>
        </td>
        <td width="6%">
            <a id="last" class="sye">末  页</a>
        </td>
        <td width="12%">当前第<span style="color:red;">${pageNum}</span>/${maxPageNum }页</td>
    </tr>
</table>
<s:hidden name="pageNum"/>
<script type="text/javascript">
    $(function(){
        //最大页=1,都隐藏
        //第一页,前2隐藏,后2显示     
        //最后一页,前2显示,后2隐藏
        //中间任意,都显示
        var pageNum = ${pageNum};
        var maxPageNum = ${maxPageNum}; 
        if(maxPageNum == 1){
            $("#fir").css("display","none");
            $("#pre").css("display","none");
            $("#next").css("display","none");
            $("#last").css("display","none");
        }else if(pageNum == 1){
            $("#fir").css("display","none");
            $("#pre").css("display","none");
            $("#next").css("display","inline");
            $("#last").css("display","inline");
        }else if(maxPageNum == pageNum){
            $("#fir").css("display","inline");
            $("#pre").css("display","inline");
            $("#next").css("display","none");
            $("#last").css("display","none");
        }else {
            $("#fir").css("display","inline");
            $("#pre").css("display","inline");
            $("#next").css("display","inline");
            $("#last").css("display","inline");
        }

        $("#fir").click(function(){
            $("[name=pageNum]").val(1);
            $("form:first").submit();
        });
        $("#pre").click(function(){
            $("[name=pageNum]").val($("[name=pageNum]").val()-1);
            $("form:first").submit();
        });
        //下一页
        $("#next").click(function(){
            //收集页码值,将页码值设置为指定值,提交表单
            //获取原始页码值,然后+1,设置回去
            $("[name=pageNum]").val($("[name=pageNum]").val()*1+1);
            $("form:first").submit();
        });
        $("#last").click(function(){
            $("[name=pageNum]").val(maxPageNum);
            $("form:first").submit();
        });
    });
</script>

四、总结

以前这样的总结还是比较少的,以至于在以后的开发,很多的模块的小的东西还需要重新的来思考,很是浪费时间,希望以后能够坚持。。。

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这里写图片描述