苏州网站建设网站制作的公司/网络整合营销是什么意思
目录
一、环境搭建
二、导入配置文夹
1.中央控制器xml
2.增删改配置文件
3.导入工具类
三、编写后端代码
1. 通用增删改查
2. BookDao类
3. book实现增删改查类
4. 分页助手类
四、编写前端代码
1. 数据显示主界面
2. 默认运行显示所有数据servlet
3. 新增、修改共用页面
一、环境搭建
对上一篇的内容优化，将之前写好的frmework包导成jar包
再导入相关jar包
二、导入配置文夹
1.中央控制器xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1"><display-name>mymvc_crud</display-name><servlet><servlet-name>mvc</servlet-name><servlet-class>com.zking.framework.DispatchServlet</servlet-class><init-param><param-name>configurationLocation</param-name><param-value>/mvc.xml</param-value></init-param></servlet><servlet-mapping><servlet-name>mvc</servlet-name><url-pattern>*.action</url-pattern></servlet-mapping>
</web-app>2.增删改配置文件
<?xml version="1.0" encoding="UTF-8"?>
<config><action path="/book" type="com.zking.web.BookAction">
<!-- 查询：BookList.jsp 返回值：list -->
<!-- * 增删改确定：book.action?methodName=list 返回值：toList -->
<!-- * 增加修改跳转对应界面：bookEdit.jsp 返回值：toEdit --><forward name="list" path="/bookList.jsp" redirect="false" /><forward name="toList" path="/book.action?methodName=list" redirect="true" /><forward name="toEdit" path="/bookEdit.jsp" redirect="false" /></action></config>3.导入工具类
进入此JSP自定义通用分页链接查看分装工具类目录
三、编写后端代码
1. 通用增删改查
package com.zking.util;import java.lang.reflect.Field;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;import com.zking.util.DBAccess;
import com.zking.util.PageBean;/*** 所有Dao层的父类* * @author 云村小威** @2023年7月3日 下午10:52:21*/
public class BaseDao<T> {/*** 通用的增删改方法* * @param book* @throws Exception*/public void executeUpdate(String sql, T t, String[] attrs) throws Exception {Connection con = DBAccess.getConnection();PreparedStatement pst = con.prepareStatement(sql);/** 思路： 1.从传进来的t中读取属性值 2.往预定义对象中设置了值* * t->book f->bid*/for (int i = 0; i < attrs.length; i++) {Field f = t.getClass().getDeclaredField(attrs[i]);f.setAccessible(true);pst.setObject(i + 1, f.get(t));}pst.executeUpdate();}/*** 通用分页查询* * @param sql* @param clz* @return* @throws Exception*/public List<T> executeQuery(String sql, Class<T> clz, PageBean pageBean) throws Exception {List<T> list = new ArrayList<T>();Connection con = DBAccess.getConnection();PreparedStatement pst = null;ResultSet rs = null;/** 是否需要分页？ 无需分页（项目中的下拉框，查询条件教员下拉框，无须分页） 必须分页（项目中列表类需求、订单列表、商品列表、学生列表...）*/if (pageBean != null && pageBean.isPagination()) {// 必须分页（列表需求）String countSQL = getCountSQL(sql);pst = con.prepareStatement(countSQL);rs = pst.executeQuery();if (rs.next()) {pageBean.setTotal(String.valueOf(rs.getObject(1)));}// 挪动到下面，是因为最后才处理返回的结果集String pageSQL = getPageSQL(sql, pageBean);// 符合条件的某一页数据pst = con.prepareStatement(pageSQL);rs = pst.executeQuery();} else {// 不分页（select需求）pst = con.prepareStatement(sql);// 符合条件的所有数据rs = pst.executeQuery();}while (rs.next()) {T t = clz.newInstance();Field[] fields = clz.getDeclaredFields();for (Field f : fields) {f.setAccessible(true);f.set(t, rs.getObject(f.getName()));}list.add(t);}return list;}/*** 将原生SQL转换成符合条件的总记录数countSQL* * @param sql* @return*/private String getCountSQL(String sql) {return "select count(1) from (" + sql + ") t";}/*** 将原生SQL转换成pageSQL* * @param sql* @param pageBean* @return*/private String getPageSQL(String sql, PageBean pageBean) {return sql + " limit " + pageBean.getStartIndex() + "," + pageBean.getRows();}
}
2. BookDao类
package com.zking.dao;import java.util.List;import com.zking.entity.Book;
import com.zking.util.BaseDao;
import com.zking.util.PageBean;
import com.zking.util.StringUtils;/*** bookdao类* @author 云村小威** @2023年7月3日 下午10:51:39*/
public class BookDao extends BaseDao<Book>{/** public void add(Book book) throws Exception {String sql = "insert into t_mvc_book values(?,?,?)";Connection con = DBAccess.getConnection();PreparedStatement pst = con.prepareStatement(sql);pst.setObject(1, book.getBid());pst.setObject(2, book.getBname());pst.setObject(3, book.getPrice());pst.executeUpdate();}增删改查的通用套路1.建立链接2.预定义对象PreparedStatement3.设置占位符的？的值4.pst.executeUpdate();1.*/public void add(Book book) throws Exception {String sql = "insert into t_mvc_book values(?,?,?)";super.executeUpdate(sql, book, new String[] {"bid","bname","price"});}public void edit(Book book) throws Exception {String sql = "update t_mvc_book set bname = ?, price = ? where bid = ?";super.executeUpdate(sql, book, new String[] {"bname","price","bid"});}public void delete(Book book) throws Exception {String sql = "delete from t_mvc_book where bid = ?";super.executeUpdate(sql, book, new String[] {"bid"});}public List<Book> list(Book book,PageBean pageBean) throws Exception {String sql = "select * from t_mvc_book where 1=1 ";String bname = book.getBname();if(StringUtils.isNotBlank(bname)) {sql += " and bname like '%"+bname+"%'";}return super.executeQuery(sql, Book.class, pageBean);}}
3. book实现增删改查类
package com.zking.web;import java.util.List;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import com.zking.dao.BookDao;
import com.zking.entity.Book;
import com.zking.framework.ActionSupport;
import com.zking.framework.ModelDriver;
import com.zking.util.PageBean;/*** book工作类* @author 云村小威** @2023年7月3日 下午10:53:52*/
public class BookAction extends ActionSupport implements ModelDriver<Book>{private Book book = new Book();private BookDao bookDao = new BookDao();@Overridepublic Book getModel() {return book;}/** 增删改最终都要跳回查询界面* 分析增删改查一共有多少结果集的配置* 查询：BookList.jsp 返回值：list* 增删改确定：book.action?methodName=list 返回值：toList* 增加修改跳转对应界面：bookEdit.jsp 返回值：toEdit*/public String add(HttpServletRequest req, HttpServletResponse resp) {try {bookDao.add(book);} catch (Exception e) {e.printStackTrace();}return "toList";}public String list(HttpServletRequest req, HttpServletResponse resp) {try {PageBean pageBean = new PageBean();pageBean.setRequest(req);List<Book> list = bookDao.list(book,pageBean);req.setAttribute("books", list);req.setAttribute("pageBean", pageBean);} catch (Exception e) {e.printStackTrace();}return "list";}public String delete(HttpServletRequest req, HttpServletResponse resp) {try {bookDao.delete(book);} catch (Exception e) {e.printStackTrace();}return "toList";}public String edit(HttpServletRequest req, HttpServletResponse resp) {try {bookDao.edit(book);} catch (Exception e) {e.printStackTrace();}return "toList";}/*** 跳转到新增修改页面* @param req* @param resp* @return*/public String toEdit(HttpServletRequest req, HttpServletResponse resp) {try {/** 如果是跳转修改页面，那么需要做bid条件的精准查询*/if(book.getBid() != 0) {List<Book> list = bookDao.list(book, null);req.setAttribute("b", list.get(0));}} catch (Exception e) {e.printStackTrace();}return "toEdit";}
}
4. 分页助手类
package com.zking.tag;import com.zking.util.PageBean;import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import java.io.IOException;
import java.util.Map;
import java.util.Set;/*** Page助手类* * @author 云村小威**/
public class PageTag extends BodyTagSupport {private static final long serialVersionUID = 1L;private PageBean pageBean;public PageBean getPageBean() {return pageBean;}public void setPageBean(PageBean pageBean) {this.pageBean = pageBean;}@Overridepublic int doStartTag() throws JspException {// 获取流JspWriter out = pageContext.getOut();try {out.print(toHTML());} catch (IOException e) {e.printStackTrace();}return SKIP_BODY;}/*** JSP自定义页面内容展示* * @return*/private String toHTML() {StringBuilder sb = new StringBuilder();// 这里拼接的是一个上一次发送的请求以及携带的参数，唯一改变的就是页码sb.append("<form id='pageBeanForm' action='" + pageBean.getUrl() + "' method='post'>");sb.append("<input type='hidden' name='page'>");// 重要设置拼接操作，将上一次请求参数携带到下一次Map<String, String[]> paMap = pageBean.getParameterMap();if (paMap != null && paMap.size() > 0) {Set<Map.Entry<String, String[]>> entrySet = paMap.entrySet();for (Map.Entry<String, String[]> entry : entrySet) {for (String val : entry.getValue()) {if (!"page".equals(entry.getKey())) {sb.append("<input type='hidden' name='" + entry.getKey() + "' value='" + val + "'>");}}}}sb.append("</form>");/*** 页码数据配置*/int page = pageBean.getPage(); //当前页码int max = pageBean.getMaxPage();//最大页码int before = page > 4 ? 4 : page - 1;//当前页码前面的页码int after = 10 - 1 - before;//当前页码后面的页码//如果最大页码没有10页，就显示当前页面后面的所有页码 max - pageafter = page + after > max ? max - page : after;// 初始页码和结束页码值判断 disabledboolean startFlag = page == 1;boolean endFlag = max == page;// 拼接分页条sb.append("<ul class='pagination'>");sb.append("<li class='page-item " + (startFlag ? "disabled" : "")+ "'><a class='page-link' href='javascript:gotoPage(1)'>首页</a></li>");sb.append("<li class='page-item " + (startFlag ? "disabled" : "")+ "'><a class='page-link' href='javascript:gotoPage(" + pageBean.getPrevPage() + ")'><</a></li>");// 代表了当前页的前4页for (int i = before; i > 0; i--) {sb.append("<li class='page-item'><a class='page-link' href='javascript:gotoPage(" + (page - i) + ")'>"+ (page - i) + "</a></li>");}sb.append("<li class='page-item active'><a class='page-link' href='javascript:gotoPage(" + pageBean.getPage()+ ")'>" + pageBean.getPage() + "</a></li>");// 代表了当前页的后5页for (int i = 1; i <= after; i++) {sb.append("<li class='page-item'><a class='page-link' href='javascript:gotoPage(" + (page + i) + ")'>"+ (page + i) + "</a></li>");}sb.append("<li class='page-item " + (endFlag ? "disabled" : "")+ "'><a class='page-link' href='javascript:gotoPage(" + pageBean.getNextPage() + ")'>></a></li>");sb.append("<li class='page-item " + (endFlag ? "disabled" : "")+ "'><a class='page-link' href='javascript:gotoPage(" + pageBean.getMaxPage() + ")'>尾页</a></li>");sb.append("<li class='page-item go-input'><b>到第</b><input class='page-link' type='text' id='skipPage' name='' /><b>页</b></li>");sb.append("<li class='page-item go'><a class='page-link' href='javascript:skipPage()'>确定</a></li>");sb.append("<li class='page-item'><b>共" + pageBean.getTotal() + "条</b></li>");sb.append("</ul>");// 拼接分页的js代码sb.append("<script type='text/javascript'>");sb.append("function gotoPage(page) {");sb.append("document.getElementById('pageBeanForm').page.value = page;");sb.append("document.getElementById('pageBeanForm').submit();");sb.append("}");sb.append("function skipPage() {");sb.append("var page = document.getElementById('skipPage').value;");sb.append("if (!page || isNaN(page) || parseInt(page) < 1 || parseInt(page) > " + max + ") {");sb.append("alert('请输入1~N的数字');");sb.append("return;");sb.append("}");sb.append("gotoPage(page);");sb.append("}");sb.append("</script>");return sb.toString();}
}
四、编写前端代码
1. 数据显示主界面
<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@taglib uri="http://jsp.ycxw.cn" prefix="w" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<linkhref="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"rel="stylesheet">
<scriptsrc="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js"></script>
<title>书籍列表</title>
<style type="text/css">
.page-item input {padding: 0;width: 40px;height: 100%;text-align: center;margin: 0 6px;
}.page-item input, .page-item b {line-height: 38px;float: left;font-weight: 400;
}.page-item.go-input {margin: 0 10px;
}
</style>
</head>
<body>
<c:if test="${empty books }">
<jsp:forward page="/BookServlet"></jsp:forward>
</c:if><form class="form-inline"action="${pageContext.request.contextPath }/book.action?methodName=list" method="post"><div class="form-group mb-2"><input type="text" class="form-control-plaintext" name="bname" placeholder="请输入书籍名称"><input name="pagination" value="false" type="hidden"></div><button type="submit" class="btn btn-primary mb-2">查询</button><a class="btn btn-primary mb-2" href="${pageContext.request.contextPath }/book.action?methodName=toEdit">新增</a></form><table class="table table-striped"><thead><tr><th scope="col">书籍ID</th><th scope="col">书籍名</th><th scope="col">价格</th><th scope="col">操作</th></tr></thead><tbody><c:forEach var="b" items="${books }"><tr><td>${b.bid }</td><td>${b.bname }</td><td>${b.price }</td><td><a href="${pageContext.request.contextPath }/book.action?methodName=toEdit&bid=${b.bid}">修改</a><a href="${pageContext.request.contextPath }/book.action?methodName=delete&bid=${b.bid}">删除</a></td></tr></c:forEach></tbody></table><!-- 这一行代码就相当于前面分页需求前端的几十行了 --><w:page pageBean="${pageBean }"></w:page>
</body>
</html>2. 默认运行显示所有数据servlet
package com.zking.web;import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;@WebServlet("/BookServlet")
public class BookServlet extends HttpServlet {private static final long serialVersionUID = 1L;protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doPost(request, response);}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {response.sendRedirect(request.getContextPath()+"/book.action?methodName=list");}}
3. 新增、修改共用页面
<%@ page language="java" contentType="text/html; charset=UTF-8"pageEncoding="UTF-8"%>
<%@ taglib uri="http://jsp.ycxw.cn" prefix="z"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<linkhref="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"rel="stylesheet">
<scriptsrc="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/js/bootstrap.js"></script>
<title>书籍新增/修改</title>
</head>
<body><form class="form-inline"action="${pageContext.request.contextPath }/book.action?methodName=${empty b ? 'add' : 'edit'}" method="post">书籍ID：<input type="text" name="bid" value="${b.bid }"><br>书籍名称：<input type="text" name="bname" value="${b.bname }"><br>书籍价格：<input type="text" name="price" value="${b.price }"><br><input type="submit"></form></body>
</html>