showimage.java

书籍源程序《J2EE应用开发（WebLogic+JBuilder）》代码

package imagefile;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import com.borland.jbcl.layout.*;
import java.sql.*;
import java.util.*;
import java.io.*;

public class ShowImage extends JFrame {
 JPanel contentPane;
 JLabel jLabel1 = new JLabel();
 XYLayout xYLayout1 = new XYLayout();

  public ShowImage() {
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
   try {
     jbInit();
   }
   catch(Exception e) {
     e.printStackTrace();
   }
  }
  private void jbInit() throws Exception  {
    contentPane = (JPanel) this.getContentPane();

    contentPane.setLayout(xYLayout1);
    String selectSQL = "select * from filetable where filename ='imagefile.jpg'";

    Properties props = new Properties();
    props.put("user",     "scott");
    props.put("password", "tiger");
    props.put("server",   "myoracle");
   try{
     Driver myDriver = (Driver)
              Class.forName("weblogic.jdbc.oci.Driver").newInstance();
      Connection con = myDriver.connect("jdbc:weblogic:oracle" , props);

    con.setAutoCommit(false);

       PreparedStatement pstmt = con.prepareStatement(selectSQL) ;

      ResultSet rs = pstmt.executeQuery() ;
      rs.next() ;

      Blob blob = rs.getBlob("filedata") ;

      // Materialize BLOB onto client

      ImageIcon icon = new ImageIcon(blob.getBytes(1, (int)blob.length())) ;
      jLabel1.setIcon(icon);
      rs.close();
      pstmt.close();
   }catch(Exception e){e.printStackTrace();}
    this.setSize(new Dimension(400, 300));
    this.setTitle("Frame Title");
    contentPane.add(jLabel1,         new XYConstraints(52, 40, 327, 225));
  }
  //Overridden so we can exit when window is closed
  protected void processWindowEvent(WindowEvent e) {
    super.processWindowEvent(e);
    if (e.getID() == WindowEvent.WINDOW_CLOSING) {
      System.exit(0);
    }
  }

  public static void main(String[] args) {
    ShowImage showImage = new ShowImage();
    showImage.setVisible(true);
  }
}