Display Blob(Image) from Mysql table using JSP

In this section, we will display blob data(image) from Mysql database table using JSP code.

A Blob stores a binary large object in the database table's row. Blob object contains a logical pointer which points to the Blob data, data is not directly stored in the row of the database table. Blob object  is valid for the duration of the transaction. The "getBlob()" and  "setBlob()" method of "ResultSet" ,"CallableStatement", and "PreparedStatement" interface , is used for accessing Blob value.

The Method defined in " java.sql.Blob " interface is as follows--

Return Type    Method                                         Description  InputStream        getBinaryStream()                       Retrieves the blob value designated                                                                                  by this blob value as a stream byte[]                 getBytes(long pos, int length)         Retrieve all or part of the blob value that                                                                                  this blob represents as an array of bytes. long                    length()                                          Returns the no of bytes in the Blob                                                                                  value designated by this Blob object OutputStream     setBinaryStream(long pos)           Retrieves a stream that can be used                                                                                  to write to the Blob value  int                       setBytes(long pos, byte[] bytes)    Write the given array of bytes to the Blob                                                                                  value that this Blob object represent                                                                                  starting at  position pos, and returns the no                                                                                  of bytes written  void                    truncate(long len)                            Truncates the blob value that this blob                                                                                   object represents to be len bytes in len

Blob data type can further be classified into four types--

• TINYBLOB: The maximum length is 255 characters (8 bits)
• BLOB: The maximum length is 16,535 characters (16 bits)
• MEDIUMBLOB: The maximum length is 16,777,216 characters (24 bits)
• LONGBLOB: The maximum length is 4,294,967,295 characters (32 bits).

EXAMPLE :

displayblob.jsp

<%@ page import="java.sql.*"%> <%@ page import="java.io.*"%> <% Blob image = null; Connection con = null; byte[ ] imgData = null ; Statement stmt = null; ResultSet rs = null; try { Class.forName("com.mysql.jdbc.Driver"); con = DriverManager.getConnection("jdbc:mysql://192.168.10.13:3306/ankdb","root","root"); stmt = con.createStatement(); rs = stmt.executeQuery("select image from inimage where id = '6'"); if (rs.next()) { image = rs.getBlob(1); imgData = image.getBytes(1,(int)image.length()); } else { out.println("Display Blob Example"); out.println("image not found for given id>"); return; } // display the image response.setContentType("image/gif"); OutputStream o = response.getOutputStream(); o.write(imgData); o.flush(); o.close(); } catch (Exception e) { out.println("Unable To Display image"); out.println("Image Display Error=" + e.getMessage()); return; } finally { try { rs.close(); stmt.close(); con.close(); } catch (SQLException e) { e.printStackTrace(); } } %>

OUTPUT :

See Also : Insert Blob(Image) in Mysql table using JSP

Download Source Code

Related Tags for Display Blob(Image) from Mysql table using JSP :

from: http://www.roseindia.net/tutorial/java/jsp/jspdisplayblob.html