Reader clobStream = clob.getCharacterStream();
StringBuffer suggestions =  new  StringBuffer();
 int  nchars =  0 ; // Number of characters read
 char [] buffer =  new   char [ 10 ];
 while ((nchars = clobStream.read(buffer)) != - 1 ) // Read from Clob
  suggestions.append(buffer,  0 , nchars); // Write to StringBuffer
  clobStream.close(); // Close the Clob input stream

suggestions

 public   void  getBlobPdfAndShow( )
  {
     try  
    {
     PreparedStatement ps = conn.prepareStatement("select d.doc from apdev.document d where d.id = ?");  
     ps.setInt( 1 , 2 ); // здесь ID документа
     ResultSet rset = ps.executeQuery();
     
       while  (rset.next()) 
      {
        oracle.sql.BLOB blob = (oracle.sql.BLOB)rset.getBlob( 1 );
         try { 
            InputStream blobStream = blob.getBinaryStream();
            FileOutputStream fileOutStream =  new  FileOutputStream("C:\\temp.pdf");
             byte [] buffer =  new   byte [ 10 ]; 
             int  nbytes =  0 ; // Number of bytes read
             while ((nbytes = blobStream.read(buffer)) != - 1 )    //Read from Blob stream    
              fileOutStream.write(buffer,  0 , nbytes); // Write to file stream

            fileOutStream.close();
            blobStream.close();
            }
         catch (IOException ioe)
            {
              ioe.printStackTrace();
            }
////////////////////////////////////////////////////////////////////////////////
            Runtime r= Runtime.getRuntime();
             try  {
                  String pdf="C:\\Program Files\\Adobe\\Acrobat 6.0\\Reader\\AcroRd32.exe "+"c:\\temp.pdf";
                  //String pdf="start "+"c:/SQL_8.pdf"; //так не работает почему-то...буду рад если объясните.
                  r.exec(pdf);
                }
             catch (Exception e)
                {
                  e.printStackTrace();
                }
////////////////////////////////////////////////////////////////////////////////

      }//конец while
     
     rset.close();
     ps.close();
     
    } 
      catch  ( SQLException sqlex ) {
          System.out.println("SQLException in getBlobPdfAndShow() method "+
                             " of given status : " + sqlex.getMessage() );    
     }
  }

java.io.FileNotFoundException: C:\temp.pdf (Процесс не может получить доступ к файлу, так как этот файл занят другим процессом.

)

	at java.io.FileOutputStream.open( Native  Method)

	at java.io.FileOutputStream.<init>(FileOutputStream.java: 179 )

	at java.io.FileOutputStream.<init>(FileOutputStream.java: 70 )

	at TestClob.getBlobPdfAndShow(TestClob.java: 220 )

	at TestClob.main(TestClob.java: 68 )