12_傳智播客JDBC_用jdbc訪問二進制類型的數據

package five.base;

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 five.utils.Utils;

//jdbc訪問其他各種數據類型.參看數據庫文檔 例如23.3. MySQL Connector/J
// 圖片 壓縮包
public class ClobTest {

 /**
  * @param args
  * @throws Exception
  */
 public static void main(String[] args) throws Exception {

  // create(3, "F:/下載/picture/X.bmp");
  read(3);

 }

 public static void create(int id, String fileName) throws IOException {

  Connection connection = null;

  PreparedStatement ps = null;

  ResultSet rs = null;
  try {
   connection = Utils.getConnection();
   String sql = "insert into picture (id, picture) values (?,?)";
   ps = connection.prepareStatement(sql);

   File file = new File(fileName);
   // 字節流
   InputStream in = new BufferedInputStream(new FileInputStream(file));

   ps.setInt(1, id);
   // 前提 Ascii
   // parameterIndex - the first parameter is 1, the second is 2, ...
   // x - the Java input stream that contains the ASCII parameter value
   // length - the number of bytes in the stream
   // ps.setAsciiStream(2, x, length)；

   // 字節流
   ps.setBinaryStream(2, in, (int) file.length());
   int i = ps.executeUpdate();
   in.close();
  } catch (SQLException e) {
   e.printStackTrace();
  } finally {
   Utils.free(connection, ps, rs);
  }
 }

 static void read(int id) throws Exception {

  // 避免依賴 應該使用接口(java.sql)的提供的類型
  Connection connection = null;
  PreparedStatement ps = null;
  ResultSet rs = null;

  try {
   // 2 創建連接
   connection = Utils.getConnection();
   // 3 創建語句
   String sql = "select picture  from picture ";
   ps = connection.prepareStatement(sql);

   // 4 執行語句
   rs = ps.executeQuery();
   // 5 處理結果
   while (rs.next()) {
    // Blob blob = rs.getBlob(1);
    // InputStream blobIn = blob.getBinaryStream();
    // 等價於上面的語句
    InputStream in = rs.getBinaryStream(1);
    
    // rs.getCharacterStream(2);
    File file = new File("D:/cgz/dayByDayJdbc/picture.bmp");
    // 裝飾模式
    // Writer writer = new BufferedWriter(new FileWriter(file));
    OutputStream out = new BufferedOutputStream(
      new FileOutputStream(file));

    // 字符流 new char[1024]
    // 字節流 new byte[1024];
    byte[] buff = new byte[1024];
    for (int i = 0; (i = in.read(buff)) > 0;) {
     out.write(buff, 0, i);
    }
    out.close();
    in.close();
   }

  } finally {
   Utils.free(connection, ps, rs);
  }
 }
}