Java by API/java.sql/Blob

Blob: getBinaryStream()

 
import java.io.ObjectInputStream;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import javax.swing.ImageIcon;
public class Main {
  public static void main(String[] args) throws Exception {
    ImageIcon image;
    Connection con = DriverManager.getConnection("jdbc:derby://localhost:1527/c:\\employee");
    Statement s = con.createStatement();
    ResultSet rs = s.executeQuery("select photo from employee where name = "Duke"");
    if (rs.next()) {
      Blob photo = rs.getBlob(1);
      ObjectInputStream ois = null;
      ois = new ObjectInputStream(photo.getBinaryStream());
      image = (ImageIcon) ois.readObject();
    } 
    s.close();
  }
}

Blob: getBytes(long pos, int length)

 
import java.sql.Blob;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import javax.swing.JPanel;
public class BlobSelect extends JPanel {
  public static void main(String args[]) throws Exception {
    Connection conn = null;
    byte[] data = getBLOB(01, conn);
  }
  public static byte[] getBLOB(int id, Connection conn) throws Exception {
    ResultSet rs = null;
    PreparedStatement pstmt = null;
    String query = "SELECT photo FROM MyPictures WHERE id = ?";
    try {
      pstmt = conn.prepareStatement(query);
      pstmt.setInt(1, id);
      rs = pstmt.executeQuery();
      rs.next();
      Blob blob = rs.getBlob("photo");
      // materialize BLOB onto client
      return blob.getBytes(1, (int) blob.length());
    } finally {
      rs.close();
      pstmt.close();
      conn.close();
    }
  }
}

Blob: length()

 
       
import java.sql.Blob;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
public class Main {
  public static void main(String args[]) throws Exception {
    Connection conn = null;
    byte[] data = getBLOB(01, conn);
  }
  public static byte[] getBLOB(int id, Connection conn) throws Exception {
    ResultSet rs = null;
    PreparedStatement pstmt = null;
    String query = "SELECT photo FROM MyPictures WHERE id = ?";
    try {
      pstmt = conn.prepareStatement(query);
      pstmt.setInt(1, id);
      rs = pstmt.executeQuery();
      rs.next();
      Blob blob = rs.getBlob("photo");
      // materialize BLOB onto client
      return blob.getBytes(1, (int) blob.length());
    } finally {
      rs.close();
      pstmt.close();
      conn.close();
    }
  }
}