JavaSE-向数据库保存图片并且读取

JavaSE-向数据库保存图片并且读取

[code]package com.xieth.sql;

import java.io.File;
import java.io.FileInputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class SqlDemo {

    private Connection conn = null;
    private PreparedStatement ps = null;

    public SqlDemo() throws ClassNotFoundException, SQLException {
        String driverClass = "com.mysql.jdbc.Driver";
        String jdbcUrl = "jdbc:mysql:///person";// localhost可以省略
        String user = "root";
        String password = "12345";

        Class.forName(driverClass); // 注册加载驱动

        conn = DriverManager.getConnection(jdbcUrl, user, password);

        System.out.println(conn); // 获取数据库连接
    }

    private void insertData() throws SQLException {
        String path = "image/Head.jpg";

        FileInputStream input = null;
        byte[] buffer = null;

        // 定义缓冲区
        try {
            input = new FileInputStream(new File(path));
            // 构建文件输入流对象
            buffer = new byte[input.available()];
            // 构建缓冲区
            input.read(buffer);
            // 将图标读入缓冲区
        } catch (Exception e) {
        } finally {
            if (input != null) {
                try {
                    input.close(); // 关闭文件输入流
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }

        String sql = "insert into user(img)" + "values(?)";

        ps = conn.prepareStatement(sql);

        ps.setBytes(1, buffer);

        int count = ps.executeUpdate();

        if (count > 0)
            System.out.println("成功");
        else
            System.out.println("失败");

    }

    private byte[] getImage() throws SQLException{
        byte[] buffer = null;

        String sql = "select img from user";

        ps = conn.prepareStatement(sql);

        ResultSet rs = ps.executeQuery();

        if (rs.next())
            buffer = rs.getBytes("img");

        return buffer;
    }

    public static void main(String[] args) throws ClassNotFoundException, SQLException {
        SqlDemo s = new SqlDemo();
        byte[] b = s.getImage();
        new MainImage(b);
    }

}

[code]package com.xieth.sql;

import java.awt.*;
import javax.swing.*;

public class MainImage extends JFrame {

    private JLabel label = null;
    private JPanel panel = null;
    private byte[] buffer = null;

    public MainImage(byte[] buffer) {
        super("Image");
        this.buffer = buffer;
        panel = new JPanel();
        init();
    }

    private void init() {
        this.setSize(540, 390); // 设置长度和宽度
        this.setLayout(null); // 自定义布局
        this.setLocationRelativeTo(this.getOwner()); // 设置窗体的相对位置
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        panel.setSize(540, 400);
        label = new JLabel(new ImageIcon(buffer));
        panel.add(label);
        add(panel);
        this.setVisible(true);

    }

}