JDBC中处置二进制类型数据

JDBC中处理二进制类型数据

package jdbc;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

/**
 *
 * @author HaoWang
 */
public class BlobTest {
    public static void main(String[] args) {
//        create(1,"C:\\a.jpg");
        read(1,"C:\\a_bak.jpg");
    }
    public static void create(int bid, String path) {
        Connection conn = null;
        String sql = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        try {
            conn = JdbcUtils.getConnection();
            sql = "insert into blob_test(bid,content) value(?,?)";
            ps = conn.prepareStatement(sql);
            ps.setInt(1, bid);
            File file = new File(path);
            InputStream in = new BufferedInputStream(new FileInputStream(file));
            ps.setBinaryStream(2, in, file.length());
            int i = ps.executeUpdate();
            System.out.println("i="+i);
            in.close();
        } catch (Exception ex) {
            System.out.println(ex.toString());
        } finally {
            JdbcUtils.free(conn, ps, rs);
        }
    }
    public static void read(int bid, String path) {
        Connection conn = null;
        String sql = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        try {
            conn = JdbcUtils.getConnection();
            sql = "select content from blob_test where bid=?";
            ps = conn.prepareStatement(sql);
            ps.setInt(1, bid);
            rs = ps.executeQuery();
            while(rs.next()) {
                InputStream in = rs.getBinaryStream(bid);
                File file = new File(path);
                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();
            }

        } catch (Exception ex) {
            System.out.println(ex.toString());
        } finally {
            JdbcUtils.free(conn, ps, rs);
        }
    }
}