最终自定义夜手机版下载 (最终篇自定义MVC框架)

文章编号：452 / 更新时间：2023-11-08 11:18:42 / 浏览：次

1.导出架包

把模型，就是我前面以model结尾命名的类和Action,ActionServlet,ModelDriver把这类导成架包，在第二篇也把这里面的东西做活数据了

大家根据下方图片进行操作即可

然后这样子就欧克呐

2.编写后端代码

2.1. 通用增删改查

首先，在写方法这里我运用了BaseDao

2.1.1 BaseDao方法

package com.sy.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;
 * 所有Dao层的父类
 *  BookDao
 *  UserDao
 *  OrderDao
 * @author Administrator
 * @param 
public class BaseDao {
   * 通用的增删改方法
   * @param book
   * @throws Exception
  public void executeUpdate(String sql, T t, String[] attrs) throws Exception {
//    String[] attrs = new String[] {"bid", "bname", "price"};
    Connection con = DBAccess.getConnection();
    PreparedStatement pst = con.prepareStatement(sql);
//    pst.setObject(1, book.getBid());
//    pst.setObject(2, book.getBname());
//    pst.setObject(3, book.getPrice());
     * 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 executeQuery(String sql,Class clz,PageBean pageBean) throws Exception{
    List list = new ArrayList();
    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
//      -- sql=SELECT * FROM t_mvc_book WHERE bname like '%圣墟%'
//      -- pageSql=sql limit (page-1)*rows,rows   对应某一页的数据
//      -- countSql=select count(1) from (sql) t  符合条件的总记录数
      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) {
//    -- countSql=select count(1) from (sql) t  符合条件的总记录数
    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) {
//    (this.page - 1) * this.rows
//    pageSql=sql limit (page-1)*rows,rows
    return sql + " limit "+ pageBean.getStartIndex() +","+pageBean.getRows();

2.2增删改查方法

相比之前，增删改查的方法的代码就很少，

package com.sy.dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.List;
import com.sy.entity.Book;
import com.sy.util.BaseDao;
import com.sy.util.PageBean;
import com.sy.util.StringUtils;
public class BookDao extends BaseDao{
   * 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PreparedStatement
    3.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 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);
  public static void main(String[] args) throws Exception {
    Book b = new Book();
    b.setBid(2323);
    b.setBname("测试www");
    b.setPrice(231f);
    BookDao bookDao = new BookDao();
//    bookDao.delete(b);
//    bookDao.add(b);
    bookDao.edit(b);

两行代码就可以解决

2.3 book实现增删改查类

package com.sy.web;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.sy.dao.BookDao;
import com.sy.entity.Book;
import com.sy.util.PageBean;
import com.zking.framework.ActionSupport;
import com.zking.framework.ModelDriver;
 * 目标：
 *  利用自己做的自定义mvc框架完成增删改查
 *  通用的分页查询
 *  通用的增删改
 * 步骤
 *  1.导入框架的jar包
 *  2.做好框架的使用配置
 *  3.一切照旧
 *    JSP、servlet/BookAction、Dao层、entity
 * @author Administrator
public class BookAction extends ActionSupport implements ModelDriver{
  private Book book = new Book();
  private BookDao bookDao = new BookDao();
  @Override
  public 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);
      pageBean.setPagination(true);
      List 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 list = bookDao.list(book, null);
        req.setAttribute("b", list.get(0));
    } catch (Exception e) {
      e.printStackTrace();
    return "toEdit";

2.4. 分页助手类

package com.sy.tag;
import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.BodyTagSupport;
import com.sy.util.PageBean;
public class PageTag extends BodyTagSupport{
  private PageBean pageBean;// 包含了所有分页相关的元素
  @Override
  public int doStartTag() throws JspException {
//    没有标签体，要输出内容
    JspWriter out = pageContext.getOut();
    try {
      out.print(toHTML());
    } catch (IOException e) {
      e.printStackTrace();
    return super.doStartTag();
  private String toHTML() {
    StringBuffer sb = new StringBuffer();
//    隐藏的form表单---这个就是上一次请求下次重新发的奥义所在
//    上一次请求的URL
    sb.append("");
    sb.append(" ");
//    上一次请求的参数
    Map paramMap = pageBean.getParamMap();
    if(paramMap != null && paramMap.size() > 0) {
      Set> entrySet = paramMap.entrySet();
      for (Entry entry : entrySet) {
//        参数名
        String key = entry.getKey();
//        参数值
        for (String value : entry.getValue()) {
//          上一次请求的参数，再一次组装成了新的Form表单
//          注意：page参数每次都会提交，我们需要避免
          if(!"page".equals(key)) {
            sb.append(" ");
    sb.append("");
//    分页条
    sb.append("");
    sb.append("     sb.append(" href='javascript:gotoPage(1)'>首页");
    sb.append("     sb.append(" href='javascript:gotoPage("+pageBean.previousPage()+")'><");// less than 小于号
//    sb.append(" 1");
//    sb.append(" 2");
    sb.append(" "+pageBean.getPage()+"");
    sb.append(" >");
    sb.append(" 尾页");
    sb.append(" 到第    sb.append(" type='text' />页");
    sb.append("     sb.append(" href='javascript:skipPage()'>确定");
    sb.append(" 共"+pageBean.getTotal()+"条");
    sb.append("");
//    分页执行的JS代码
    sb.append("");
    return sb.toString();

3.配置文件

3.1 mvc.xml文件

3.2 web.xml文件

这个里面放入中央控制器，就是架包里面的东西


  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"
  version="3.1">
  mvc_crud
  
    index.html
    index.htm
    index.jsp
    default.html
    default.htm
    default.jsp
  
  
    mvc
    com.zking.framework.DispatchServlet
    
      configurationLocation
      /mvc.xml
    
  
  
    mvc
    *.action

3.3 .tld文件

这个就是分页的标签


    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-jsptaglibrary_2_0.xsd"
    version="2.0">
  shenyan 1.1 core library
  shenyan core
  1.1
  s
  http://shenyan
  
    page
    com.shenyan.Tag.PageTag
    JSP
    
        pageBean
        true
        true

4.编写前端代码

4.1. 数据显示主界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
  pageEncoding="UTF-8"%>
<%@ taglib uri="http://shenyan" prefix="s"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>




  href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
  rel="stylesheet">

书籍列表



      action="${pageContext.request.contextPath }/book.action?methodName=list"
    method="post">
    
              placeholder="请输入书籍名称">
      
    
    
          href="${pageContext.request.contextPath }/book.action?methodName=toEdit">新增
  
                                                                
                                                              
      


书籍ID
书籍名
价格
操作




${b.bid }
${b.bname }
${b.price }
            href="${pageContext.request.contextPath }/book.action?methodName=toEdit&bid=${b.bid}">修改
                        href="${pageContext.request.contextPath }/book.action?methodName=delete&bid=${b.bid}">删除

书籍ID	书籍名	价格	操作
${b.bid }	${b.bname }	${b.price }	href="${pageContext.request.contextPath }/book.action?methodName=toEdit&bid=${b.bid}">修改 href="${pageContext.request.contextPath }/book.action?methodName=delete&bid=${b.bid}">删除

4.2. 新增、修改共用页面

<%@ page language="java" contentType="text/html; charset=UTF-8"
  pageEncoding="UTF-8"%>
<%@ taglib uri="http://shenyan" prefix="s"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>




  href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/4.5.0/css/bootstrap.css"
  rel="stylesheet">

书籍新增/修改


      action="${pageContext.request.contextPath }/book.action?methodName=${empty b ? 'add' : 'edit'}"
    method="post">
    书籍ID：

    书籍名称：

    书籍价格：