数据库名：db_file_test

表名：obj

实体类：

package com.bean;

import java.io.Serializable;

public class User implements Serializable {

private String name;

private String password;

public User() {

super();

// TODO Auto-generated constructor stub

}

public User(String name, String password) {

super();

this.name = name;

this.password = password;

}

@Override

public String toString() {

return "User [name=" + name + ", password=" + password + "]";

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getPassword() {

return password;

}

public void setPassword(String password) {

this.password = password;

}

}

数据库连接的工具类：

package com.utils;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.SQLException;

public class DBConnection {

static String url = "jdbc:mysql://localhost:3306/db_file_test?useUnicode=true&characterEncoding=UTF-8";

static String db_user = "root";

static String db_password = "root";

static Connection conn = null;

static {

// 加载驱动

try {

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

conn = DriverManager.getConnection(url, db_user, db_password);

} catch (ClassNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

public static Connection getConnection() {

return conn;

}

}

存取对象信息的核心工具类：

package com.utils;

import java.io.IOException;

import java.io.ObjectInputStream;

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import com.bean.User;

public class DBUtils {

public int addObject(User user) {

String name = user.getName();

String sql = "insert into obj(name,value)values(?,?)";

Connection conn = DBConnection.getConnection();

try {

PreparedStatement ps = conn.prepareStatement(sql);

ps.setString(1, name);

ps.setObject(2, user);

int result = ps.executeUpdate();

return result;

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return 0;

}

public User getObj(String name) {

Connection conn = DBConnection.getConnection();

String sql = "select * from obj where name=?";

try {

PreparedStatement ps = conn.prepareStatement(sql);

ps.setString(1, name);

ResultSet rs = ps.executeQuery();

while (rs.next()) {

ObjectInputStream ois = new ObjectInputStream(

rs.getBinaryStream("value"));

User user = (User) ois.readObject();

System.out.println("getObj-->" + user.toString());

return user;

}

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

} catch (ClassNotFoundException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

return null;

}

}

测试类：

将对象添加进数据库：

package com.test;

import com.bean.User;

import com.utils.DBUtils;

public class Test1 {

public static void main(String[] args) {

DBUtils utils = new DBUtils();

User user = new User("小明", "123456");

if (utils.addObject(user) != 0) {

System.out.println("添加成功！");

}

}

}

从数据库中读取出对象信息：

package com.test;

import com.bean.User;

import com.utils.DBUtils;

public class Test1 {

public static void main(String[] args) {

DBUtils utils = new DBUtils();

User user = utils.getObj("小明");

System.out.println(user.toString());

}

}