UpdateBatch and CancelBatch Methods Example (VJ++)

This example demonstrates the UpdateBatch method in conjunction with the CancelBatch method.

// BeginUpdateBatchJ
import java.io.*;
import com.ms.wfc.data.*;

public class UpdateBatchX
{
   // The main entry point of the application.
   public static void main (String[] args)
   {
      UpdateBatchX();
      System.exit(0);
   }
   // UpdateBatchX Function

   static void UpdateBatchX()
   {
      // Define ADO Objects.
      Recordset rstTitles = null;

      // Declarations.
      String strCnn = "Provider='sqloledb';Data Source='MySqlServer';"+
                  "Initial Catalog='Pubs';Integrated Security='SSPI';";
      String strTitle;
      String strMessage;
      BufferedReader in = 
         new BufferedReader(new InputStreamReader(System.in));

      try
      {
         rstTitles = new Recordset();
         rstTitles.setCursorType(AdoEnums.CursorType.KEYSET);
         rstTitles.setLockType(AdoEnums.LockType.BATCHOPTIMISTIC);
         rstTitles.open("Titles", strCnn, AdoEnums.CursorType.KEYSET, 
            AdoEnums.LockType.BATCHOPTIMISTIC, 
            AdoEnums.CommandType.TABLE);

         rstTitles.moveFirst();

         // Loop through recordset and ask user if she wants
         // to change the type for the specified table.
         while(!rstTitles.getEOF())
         {
            if(rstTitles.getField("Type").getString().
               trim().equalsIgnoreCase("psychology"))
            {
               strTitle = rstTitles.getField("Title").getString();
               strMessage = "Title: "+ strTitle + "\n" + 
                  "Change type to self_help?Enter (Y/N)";
               System.out.println(strMessage);
               if(in.readLine().trim().equalsIgnoreCase("Y"))
                  rstTitles.getField("type").setString("self_help");
            }
            rstTitles.moveNext();
         }
         // Ask the user if she wants to commit to all the
         // changes made above.
         System.out.println("Save all changes?Enter (Y/N)");
         if(in.readLine().trim().equalsIgnoreCase("Y"))
            rstTitles.updateBatch();
         else
            rstTitles.cancelBatch();

         // Print current data in recordset.
         rstTitles.requery();
         rstTitles.moveFirst();
         while(!rstTitles.getEOF())
         {
         System.out.println(rstTitles.getField("title").getString() +
            " - " + rstTitles.getField("type").getString());
         rstTitles.moveNext();
         }

         // Restore original values because this is a demonstration.
         rstTitles.moveFirst();
         while(!rstTitles.getEOF())
         {
            if(rstTitles.getField("type").getString().
               trim().equalsIgnoreCase("self_help"))
               rstTitles.getField("type").setString("psychology");
            rstTitles.moveNext();
         }
         rstTitles.updateBatch();

         System.out.println("Press <Enter> to continue..");
         in.readLine();

      }
      catch(AdoException ae)
      {
         // Notify the user of any errors that result from ADO.

         // As passing a recordset, check for null pointer first.
         if(rstTitles != null)
         {
            PrintProviderError(rstTitles.getActiveConnection());
         }
         else
         {
            System.out.println("Exception: " + ae.getMessage());
         }
      }
      // System read requires this catch.
      catch(java.io.IOException je)
      {
         PrintIOError(je);
      }   
      
      finally
      {
         // Cleanup objects before exit.   
         if (rstTitles != null)
            if (rstTitles.getState() == 1)
               rstTitles.close();
      }
   }

   // PrintProviderError Function
   static void PrintProviderError(Connection cnn1)
   {
      // Print Provider Errors from Connection Object.
      // ErrItem is an item object in the Connection’s Errors Collection.
      com.ms.wfc.data.Error               ErrItem = null;
      long                                 nCount = 0;
      int                                       i = 0;

      nCount = cnn1.getErrors().getCount();

      // If there are any errors in the collection, print them.
      if ( nCount > 0)
      {
         // Collection ranges from 0 to nCount-1.
         for ( i=0;i<nCount; i++)
         {
            ErrItem = cnn1.getErrors().getItem(i);
            System.out.println("\t Error Number: " + ErrItem.getNumber() 
               + "\t" + ErrItem.getDescription());
         }
      }
   }
   // PrintIOError Function
   static void PrintIOError(java.io.IOException je)
   {
      System.out.println("Error: \n");
      System.out.println("\t Source: " + je.getClass() + "\n");
      System.out.println("\t Description: "+ je.getMessage() + "\n");
   }
}
// EndUpdateBatchJ

See Also

CancelBatch Method | UpdateBatch Method