一个存储和读取二进制图片的例子
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class BlobTest {
public static void main(String[] args) throws SQLException, IOException {
// create();
read();
}
static void read() throws SQLException, IOException {
Connection conn = null;
Statement st = null;
ResultSet rs = null;
try {
// 2.建立连接
conn = JdbcUtils.getConnection();
// conn = JdbcUtilsSing.getInstance().getConnection();
// 3.创建语句
st = conn.createStatement();
// 4.执行语句
rs = st.executeQuery("select big_bit from blob_test");
// 5.处理结果
while (rs.next()) {
// Blob blob = rs.getBlob(1);
// InputStream in = blob.getBinaryStream();
InputStream in = rs.getBinaryStream("big_bit");
File file = new File("IMG_0002_bak.jpg");
OutputStream out = new BufferedOutputStream(
new FileOutputStream(file));
byte[] buff = new byte[1024];
for (int i = 0; (i = in.read(buff)) > 0;) {
out.write(buff, 0, i);
}
out.close();
in.close();
}
} finally {
JdbcUtils.free(rs, st, conn);
}
}
static void create() throws SQLException, IOException {
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
try {
// 2.建立连接
conn = JdbcUtils.getConnection();
// conn = JdbcUtilsSing.getInstance().getConnection();
// 3.创建语句
String sql = "insert into blob_test(big_bit) values (?) ";
ps = conn.prepareStatement(sql);
File file = new File("IMG_0002.jpg");
InputStream in = new BufferedInputStream(new FileInputStream(file));
ps.setBinaryStream(1, in, (int) file.length());
// 4.执行语句
int i = ps.executeUpdate();
in.close();
System.out.println("i=" + i);
} finally {
JdbcUtils.free(rs, ps, conn);
}
}
}
