自定义MV3
自定义MVC(三)-优化
我们 完成上篇博客的最后一步，进行优化，我们已经把工具类都写好了，接下来我们可以把自己写好的工具类打成一个jar包，来测试调用可不可行
点击Export -> 点击 JAR File ->
勾选你要打成jar包的工具类，我在这里全部勾选了
保存到你要保存的位置
接下来我们重新创建一个项目，把我们的jar包导进来进行测试
写了一个book实体类
private int bid;
private String bname;
private float price;
创建通用dao方法
BaseDao
package util;
import java.lang.reflect.Field;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import entity.Book;
public class BaseDao {
private static final String T = null;
Connection con=null;
PreparedStatement ps=null;
ResultSet rs=null;
public List executeQuery(String sql,Class clz,PageBean pagebean) throws InstantiationException, IllegalAccessException, SQLException{
List list;
try {
list = new ArrayList<>();
con = DBAccess.getConnection();
if (pagebean != null && pagebean.isPagination()) {
//该分页了
String countSql=getCountSql(sql);
ps=con.prepareStatement(countSql);
rs=ps.executeQuery();
if(rs.next()) {
pagebean.setTotal(rs.getLong(1)+"");
}
String pageSql=getPageSql(sql,pagebean);
ps=con.prepareStatement(pageSql);
rs=ps.executeQuery();
} else {
ps = con.prepareStatement(sql);
rs = ps.executeQuery();
}
while (rs.next()) {
T t = (T) clz.newInstance();
Field[] fields = clz.getDeclaredFields();
for (Field field : fields) {
field.setAccessible(true);
field.set(t, rs.getObject(field.getName()));
}
list.add(t);
}
} finally {
//
DBAccess.close(con);
}
return list;
}
private String getPageSql(String sql, PageBean pagebean) {
return sql + " limit "+pagebean.getStartIndex() +","+pagebean.getRows();
}
private String getCountSql(String sql) {
// TODO Auto-generated method stub
return "select count(1) from ("+sql+") t";
}
/**
* 通用的增删改方法
* @param sql 增删改sql语句
* @param attrs ?所代表的数据库的实体类的属性
* @param t 实体类的实例
* @return
* @throws SQLException
* @throws NoSuchFieldException
* @throws SecurityException
* @throws IllegalArgumentException
* @throws IllegalAccessException
*/
public int executeUpdate(String sql,String[] attrs,T t) throws SQLException, NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
Connection con = DBAccess.getConnection();
PreparedStatement ps = con.prepareStatement(sql);
for (int i = 0; i < attrs.length; i++) {
Field field = t.getClass().getDeclaredField(attrs[i]);
field.setAccessible(true);
ps.setObject(i+1, field.get(t));
}
return ps.executeUpdate();
}
}
继承通用BaseDao方法
** BookDao **
package dao;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.List;
import com.mysql.jdbc.StringUtils;
import entity.Book;
import util.BaseDao;
import util.DBAccess;
import util.PageBean;
public class BookDao extends BaseDao{
public List list(Book book,PageBean pageBean) throws InstantiationException, IllegalAccessException, SQLException{
String sql="select * from t_mvc_book where 1=1";
if(util.StringUtils.isNotBlank(book.getBname())) {
sql+=" and bname like '%"+book.getBname()+"%'";
}
return super.executeQuery(sql, Book.class, pageBean);
}
//增加
public int add(Book book) throws SQLException, NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
String sql="insert into t_mvc_book values(?,?,?)";
return super.executeUpdate(sql, new String[] {"bid","bname","price"}, book);
}
//删除
public int delete(Book book) throws SQLException, NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
String sql="delete from t_mvc_book where bid=?";
return super.executeUpdate(sql, new String[] {"bid"}, book);
}
//修改
public int update(Book book) throws SQLException, NoSuchFieldException, SecurityException, IllegalArgumentException, IllegalAccessException {
String sql="update t_mvc_book set bname=?,price=? where bid=?";
return super.executeUpdate(sql, new String[] {"bname","price","bid"}, book);
}
}
通用分页
Page Bean
package util;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.tagext.BodyTagSupport;
/**
* 分页工具类
*
*/
public class PageBean{
private int page = 1;// 页码
private int rows = 10;// 页大小
private int total = 0;// 总记录数
private boolean pagination = true;// 是否分页
private String url;
private Map paramMap = new HashMap<>();
public void setRequest(HttpServletRequest req) {
this.setPage(req.getParameter("page"));
this.setRows(req.getParameter("rows"));
this.setPagination(req.getParameter("pagination"));
// getRequestURL获取到浏览器请求的全路径
this.setUrl(req.getRequestURL().toString());
// getParameterMap可以获取到一次url请求所携带的所有参数
this.setParamMap(req.getParameterMap());
}
public void setPagination(String pagination) {
if (StringUtils.isNotBlank(pagination)) {
this.setPagination(!"false".equals(pagination));
}
}
public void setRows(String rows) {
if (StringUtils.isNotBlank(rows))
this.setRows(Integer.valueOf(rows));
}
public void setPage(String page) {
if (StringUtils.isNotBlank(page)) {
this.setPage(Integer.valueOf(page));
}
}
public PageBean() {
super();
}
public String getUrl() {
return url;
}
public void setUrl(String url) {
this.url = url;
}
public Map getParamMap() {
return paramMap;
}
public void setParamMap(Map paramMap) {
this.paramMap = paramMap;
}
public int getPage() {
return page;
}
public void setPage(int page) {
this.page = page;
}
public int getRows() {
return rows;
}
public void setRows(int rows) {
this.rows = rows;
}
public int getTotal() {
return total;
}
public void setTotal(int total) {
this.total = total;
}
public void setTotal(String total) {
this.total = Integer.parseInt(total);
}
public boolean isPagination() {
return pagination;
}
public void setPagination(boolean pagination) {
this.pagination = pagination;
}
/**
* 获得起始记录的下标
*
* @return
*/
public int getStartIndex() {
return (this.page - 1) * this.rows;
}
@Override
public String toString() {
return "PageBean [page=" + page + ", rows=" + rows + ", total=" + total + ", pagination=" + pagination + "]";
}
/**
* 获取到总页数
* @return
*/
public int getMaxPage() {
return this.total % this.rows == 0 ?
this.total / this.rows :
(this.total / this.rows) + 1;
}
/**
* 获取下一页页码
* @return
*/
public int getNextPage() {
return this.page < this.getMaxPage() ? this.page+1 : this.page;
}
/**
* 获取上一页页码
* @return
*/
public int getPreviousPage() {
return this.page > 1 ? this.page-1 : this.page;
}
}
创建子控制器
BookAction
package web;
import java.sql.SQLException;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.liuting.framework.ActionSupport;
import com.liuting.framework.ModelDriven;
import dao.BookDao;
import entity.Book;
import util.PageBean;
public class BookAction extends ActionSupport implements ModelDriven{
private BookDao bookDao=new BookDao();
private Book book=new Book();
/**
* 查询分页的数据
* @param req
* @param resp
* @return
*/
public String list(HttpServletRequest req,HttpServletResponse resp) {
try {
PageBean pageBean=new PageBean();
pageBean.setRequest(req);
List list = this.bookDao.list(book, pageBean);
req.setAttribute("bookList", list);
req.setAttribute("pageBean", pageBean);
} catch (InstantiationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "list";
}
/**
* 增加书籍
* @param req
* @param resp
* @return
*/
public String add(HttpServletRequest req,HttpServletResponse resp) {
try {
int n = this.bookDao.add(book);
} catch (NoSuchFieldException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "toList";
}
/**
* 删除书籍
* @param req
* @param resp
* @return
*/
public String delete(HttpServletRequest req,HttpServletResponse resp) {
try {
int n = this.bookDao.delete(book);
} catch (NoSuchFieldException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "toList";
}
/**
* 加载当前所需要修改的书籍信息
* @param req
* @param resp
* @return
*/
public String load(HttpServletRequest req,HttpServletResponse resp) {
try {
List list=this.bookDao.list(book, null);
req.setAttribute("book", list.get(0));
} catch (InstantiationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "toEdit";
}
/**
* 开始修改书籍信息
* @param req
* @param resp
* @return
*/
public String update(HttpServletRequest req,HttpServletResponse resp) {
try {
int n = this.bookDao.update(book);
} catch (NoSuchFieldException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalArgumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return "toList";
}
@Override
public Book getModel() {
// TODO Auto-generated method stub
return book;
}
}
配置XML
web.xml
mvc_curd
encodingFiter
util.EncodingFiter
encodingFiter
/*
dispatherServlet
com.framework.DispatherServlet
xmlPath
/mvc.xml
dispatherServlet
*.action
mvc.xml
jsp页面内容
<%@ 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="/zking" prefix="z" %>
Insert title here
小说目录
编号
名称
价格
操作
${b.bid }
${b.bname }
${b.price }
${pageBean}
修改和增加页面
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
Insert title here
最后进行测试，这样我们的自定义mvc模式就完成了