标签:nbsp div main last state exe 取图 mysq result
一:建表
二:获取数据库连接
1:导入mysql的驱动jar包,mysql-connector-java-5.1.8-bin.jar
2:写代码连接数据库,如下:
1 /**
2 *
3 */
4 package com.hlcui.file;
5
6 import java.sql.Connection;
7 import java.sql.DriverManager;
8 import java.sql.SQLException;
9
10 /**
11 * @author Administrator
12 *
13 */
14 public class DBUtil {
15 // 定义数据库连接参数
16 public static final String DRIVER_CLASS_NAME = "com.mysql.jdbc.Driver";
17 public static final String URL = "jdbc:mysql://localhost:3306/test";
18 public static final String USERNAME = "root";
19 public static final String PASSWORD = "root";
20
21 // 注册数据库驱动
22 static {
23 try {
24 Class.forName(DRIVER_CLASS_NAME);
25 } catch (ClassNotFoundException e) {
26 System.out.println("注册失败!");
27 e.printStackTrace();
28 }
29 }
30
31 // 获取连接
32 public static Connection getConn() throws SQLException {
33 return DriverManager.getConnection(URL, USERNAME, PASSWORD);
34 }
35
36 // 关闭连接
37 public static void closeConn(Connection conn) {
38 if (null != conn) {
39 try {
40 conn.close();
41 } catch (SQLException e) {
42 System.out.println("关闭连接失败!");
43 e.printStackTrace();
44 }
45 }
46 }
47 //测试
48 public static void main(String[] args) throws SQLException {
49 System.out.println(DBUtil.getConn());
50 }
51
52 }
三:封装读取图片的流
1 /**
2 *
3 */
4 package com.hlcui.file;
5
6 import java.io.File;
7 import java.io.FileInputStream;
8 import java.io.FileOutputStream;
9 import java.io.IOException;
10 import java.io.InputStream;
11
12 /**
13 * @author Administrator
14 *
15 */
16 public class ImageUtil {
17
18 // 读取本地图片获取输入流
19 public static FileInputStream readImage(String path) throws IOException {
20 return new FileInputStream(new File(path));
21 }
22
23 // 读取表中图片获取输出流
24 public static void readBin2Image(InputStream in, String targetPath) {
25 File file = new File(targetPath);
26 String path = targetPath.substring(0, targetPath.lastIndexOf("/"));
27 if (!file.exists()) {
28 new File(path).mkdir();
29 }
30 FileOutputStream fos = null;
31 try {
32 fos = new FileOutputStream(file);
33 int len = 0;
34 byte[] buf = new byte[1024];
35 while ((len = in.read(buf)) != -1) {
36 fos.write(buf, 0, len);
37 }
38 fos.flush();
39 } catch (Exception e) {
40 e.printStackTrace();
41 } finally {
42 if (null != fos) {
43 try {
44 fos.close();
45 } catch (IOException e) {
46 e.printStackTrace();
47 }
48 }
49 }
50 }
51 }
四:实现图片(本地、数据库互相传输)
1 /**
2 *
3 */
4 package com.hlcui.file;
5
6 import java.io.FileInputStream;
7 import java.io.InputStream;
8 import java.sql.Connection;
9 import java.sql.PreparedStatement;
10 import java.sql.ResultSet;
11 import java.sql.SQLException;
12
13 /**
14 * @author Administrator 测试写入数据库以及从数据库中读取
15 */
16 public class ImageDemo {
17
18 // 将图片插入数据库
19 public static void readImage2DB() {
20 String path = "D:/1.png";
21 Connection conn = null;
22 PreparedStatement ps = null;
23 FileInputStream in = null;
24 try {
25 in = ImageUtil.readImage(path);
26 conn = DBUtil.getConn();
27 String sql = "insert into photo (id,name,photo)values(?,?,?)";
28 ps = conn.prepareStatement(sql);
29 ps.setInt(1, 1);
30 ps.setString(2, "Tom");
31 ps.setBinaryStream(3, in, in.available());
32 int count = ps.executeUpdate();
33 if (count > 0) {
34 System.out.println("插入成功!");
35 } else {
36 System.out.println("插入失败!");
37 }
38 } catch (Exception e) {
39 e.printStackTrace();
40 } finally {
41 DBUtil.closeConn(conn);
42 if (null != ps) {
43 try {
44 ps.close();
45 } catch (SQLException e) {
46 e.printStackTrace();
47 }
48 }
49 }
50
51 }
52
53 // 读取数据库中图片
54 public static void readDB2Image() {
55 String targetPath = "D:/image/1.png";
56 Connection conn = null;
57 PreparedStatement ps = null;
58 ResultSet rs = null;
59 try {
60 conn = DBUtil.getConn();
61 String sql = "select * from photo where id =?";
62 ps = conn.prepareStatement(sql);
63 ps.setInt(1, 1);
64 rs = ps.executeQuery();
65 while (rs.next()) {
66 InputStream in = rs.getBinaryStream("photo");
67 ImageUtil.readBin2Image(in, targetPath);
68 }
69 } catch (Exception e) {
70 e.printStackTrace();
71 } finally {
72 DBUtil.closeConn(conn);
73 if (rs != null) {
74 try {
75 rs.close();
76 } catch (SQLException e) {
77 e.printStackTrace();
78 }
79 }
80 if (ps != null) {
81 try {
82 ps.close();
83 } catch (SQLException e) {
84 e.printStackTrace();
85 }
86 }
87
88 }
89 }
90 //测试
91 public static void main(String[] args) {
92 //readImage2DB();
93 readDB2Image();
94 }
95 }
标签:nbsp div main last state exe 取图 mysq result
原文地址:http://www.cnblogs.com/ayuwang/p/6295502.html