解决JDBC中日期和文件类型的问题

1.解决了mysql中日期类型的写入和读取转换问题；

2.解决了mysql中文本类型的写入和读取的问题；

3.java.util.Date和java.sql.Date的转换问题。

项目目录：

数据库表结构：

1.数据库配置文件

jdbc.properties

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/数据库名?characterEncoding=utf-8
user=root
password=

2.编写数据库工具类

JdbcUtil.java

package utils;

import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;



public class JdbcUtil {
   private static String url;
   private static String user;
   private static String password;
   
   static {
	   //使用properties加载属性文件
	   Properties prop = new Properties();
	   try {
		   InputStream is = JdbcUtil.class.getClassLoader().getResourceAsStream("jdbc.properties");
		   prop.load(is);
		   //获取属性文件中的数据，注册驱动
		   String driverClassName = prop.getProperty("driverClassName");
		   Class.forName(driverClassName);
		   //获取属性文件中url、username、password
		   url = prop.getProperty("url");
		   user = prop.getProperty("user");
		   password = prop.getProperty("password");
	   }catch(Exception e) {
		   e.printStackTrace();
	   }
   }
   
   //获取数据库连接
   public static Connection getConnection() {
	  Connection conn = null;
	   try {
		conn =DriverManager.getConnection(url, user, password);
	} catch (SQLException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}
	   return conn;
   }
   
   //释放资源
   public static void close(Connection conn,Statement stmt,ResultSet rs) {
	   if(conn!=null) {
		   try {
			conn.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	   }
	   if(stmt!=null) {
		   try {
			stmt.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	   }
	   if(rs!=null) {
		   try {
			rs.close();
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	   }
   }
}

3.处理日期和文件写入与读取的问题

package test;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Reader;
import java.sql.Connection;
import java.sql.Date;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.List;

import model.Student;
import utils.JdbcUtil;

public class Test {
	public static void main(String[] args) {
		add();

		List<Student> stuList = selectAll();
		for (int i = 0; i < stuList.size(); i++) {
			System.out.println(stuList.get(i));
		}
	}

	private static boolean add() {
		boolean flag = false;
		Connection conn = null;
		PreparedStatement stmt = null;
		conn = JdbcUtil.getConnection();
		String sql = "insert into student(stuName,birthday,introduce) values(?,?,?);";
		try {
			stmt = conn.prepareStatement(sql);
			stmt.setString(1, "Tao");

			// 写入日期,解决两种日期不同的问题，java.util.date->java.sql.date
			SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
			java.util.Date birthday = sdf.parse("2016-05-26");
			System.out.println("birthday:" + birthday);
			System.out.println("birthday.getTime():" + birthday.getTime());
			stmt.setDate(2, new Date(birthday.getTime()));

			// 写入文本
			// 创建文件字符流对象
			File file = new File("src\\introduce.txt");
			FileReader reader = new FileReader(file);
			BufferedReader bufferedReader = new BufferedReader(reader);

			stmt.setCharacterStream(3, bufferedReader, file.length());

			int row = stmt.executeUpdate();
			if (row > 0) {
				System.out.println("写入成功！");
			}
			flag = row > 0 ? true : false;
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (ParseException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			JdbcUtil.close(conn, stmt, null);
		}
		return flag;
	}

	private static List<Student> selectAll() {
		List<Student> stuList = new ArrayList<Student>();
		boolean flag = false;
		Connection conn = null;
		PreparedStatement stmt = null;
		ResultSet rs = null;

		conn = JdbcUtil.getConnection();
		String sql = "select * from student";
		try {
			stmt = conn.prepareStatement(sql);
			rs = stmt.executeQuery();
			while (rs.next()) {
				String stuName = rs.getString("stuName");

				// 获取日期，解决两种日期不同的问题,java.sql.date->java.util.date
				Date birthdaySqlDate = rs.getDate("birthday");
				SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
				java.util.Date birthdayUtilDate = new java.util.Date(birthdaySqlDate.getTime());

				// 获取文本
				Reader reader = rs.getCharacterStream("introduce");
				BufferedReader bufferedReader = new BufferedReader(reader);
				String temp = null;
				String introduce = "";
				BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter("src\\introduce2.txt"));
				while ((temp = bufferedReader.readLine()) != null) {
					bufferedWriter.write(temp);
					introduce += temp;
				}
				bufferedWriter.close();
				bufferedReader.close();

				Student student = new Student(stuName, birthdayUtilDate, introduce);

				stuList.add(student);
			}
		} catch (SQLException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			JdbcUtil.close(conn, stmt, rs);
		}
		return stuList;
	}
}

解决JDBC中日期和文件类型的问题

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