public byte[] getSignatureByteArrayFromDb(String columnName, String id, Connection con) {
		byte[] file;
		PreparedStatement ps = null;
		try {
			ps = con.prepareStatement("SELECT table1.original FROM test.table1 table1 WHERE table1.id = ? ");
			ps.setString(1, id);
		} catch (SQLException se) {
			System.out.println("We got an exception while preparing a statement: Probably bad SQL.");
			se.printStackTrace();
		}
		
		ResultSet rs = null;
		try {
			rs = ps.executeQuery();
		} catch (SQLException se) {
			System.out.println("We got an exception while executing an update:" +
							 "possibly bad SQL, or check the connection.");
			se.printStackTrace();		  
		} 
		
		try {
			if (rs != null) {
				while(rs.next()) {
				//getBytes(java.lang.String columnName)	
					file = rs.getBytes(1);
				}
				rs.close();
			}
			ps.close();
		} catch (Exception ex) {
			System.out.println("getSignatureByteArrayFromDb: " + ex);
			ex.printStackTrace();
		} 
			
		
		return file;
}

byte[] a = new byte[0]; 
a = new byte[100];