数据库使用mysql，如下：

vo包的Sales类：

package com.vo;

public class Sales {

public String salestime;

public float salesnum;

public String getSalestime() {

return salestime;

}

public void setSalestime(String salestime) {

this.salestime = salestime;

}

public float getSalesnum() {

return salesnum;

}

public void setSalesnum(float salesnum) {

this.salesnum = salesnum;

}

}

dao包中的DBManager类：

package com.dao;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

public class DbManager {

private static String URL = "jdbc:mysql://localhost:3306/sales";

private static String USER = "root";

private static String PWD = "root";

public static Connection getConn(){

Connection conn = null;

try {

Class.forName("com.mysql.jdbc.Driver");

conn = DriverManager.getConnection(URL,USER,PWD);

} catch (SQLException e) {

e.printStackTrace();

} catch (ClassNotFoundException e) {

e.printStackTrace();

}

return conn;

}

public static void closeAll(Connection conn,Statement ste,ResultSet rs){

if(rs != null){

try {

rs.close();

} catch (SQLException e) {

e.printStackTrace();

}

}

if(ste !=null){

try {

ste.close();

} catch (SQLException e) {

e.printStackTrace();

}

}

if(conn !=null){

try {

conn.close();

} catch (SQLException e) {

e.printStackTrace();

}

}

}

}

dao包中的SalesDao类：

package com.dao;

import java.sql.Connection;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.ArrayList;

import java.util.List;

import com.vo.Sales;

public class SalesDao {

public List find(String month) {

Connection con = null;

Statement state = null;

ResultSet resultSet = null;

List list = null;

String sql = "select * from sales where salestime like '" + month + "-%'" ;

con = DbManager.getConn();

try {

state = con.createStatement();

resultSet = state.executeQuery(sql);

while(resultSet.next()){

if(null == list){

list = new ArrayList();

}

Sales sales = new Sales();

sales.setSalestime(resultSet.getString("salestime"));

sales.setSalesnum(resultSet.getFloat("salesnum"));

list.add(sales);

}

} catch (SQLException e) {

e.printStackTrace();

}finally{

DbManager.closeAll(con, state, resultSet);

}

return list;

}

}

index.jsp页面：

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

%>

My JSP 'index.jsp' starting page

请选择查询的月份:

1月

2月

3月

4月

5月

6月

7月

8月

9月

10月

11月

12月

show.jsp页面：

String path = request.getContextPath();

String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

%>

My JSP 'show.jsp' starting page

销售日期

销售额

String month = request.getParameter("month");

SalesDao dao = new SalesDao();

List list = dao.find(month);

if(list != null){

for(Sales sales : list){

%>

}

}else{

%>

暂时没有数据

}

%>

结果展示：

如图，选择1月，点击查询按钮，出现如下情况：