MDAC 2.5 SDK - ADO

Move Method Example (VJ++)

See Also

This example uses the Move method to position the record pointer based on user input.

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

public class MoveX
{
// The main entry point for the application.

public static void main (String[] args)
{
   MoveX();
   System.exit(0);
}
// MoveX Function

static void MoveX()
{
   // Define ADO Objects
   Recordset rstAuthors = null;

   // Declarations
   String line = null;
   Variant varBookmark;
   String strCommand = null;
   int lngMove;
   BufferedReader in = 
      new BufferedReader(new InputStreamReader(System.in));

   try
   {
      //  Open recordset from Authors table.
      String strCnn = "Provider=sqloledb;Data Source=srv;"+
         "Initial Catalog=Pubs;User Id=sa;Password=;";

      rstAuthors = new Recordset();
      rstAuthors.setCursorType(AdoEnums.CursorType.STATIC);

      // Use client cursor to allow use of
      // Absolute Position property.
      rstAuthors.setCursorLocation(AdoEnums.CursorLocation.CLIENT);
      rstAuthors.open("select au_id,au_fname,au_lname,city,state " + 
         "from Authors order by au_lname", 
         strCnn,AdoEnums.CursorType.STATIC, 
         AdoEnums.CursorLocation.CLIENT, AdoEnums.CommandType.TEXT);

      rstAuthors.moveFirst();

      while(true)
      {
         // Display information about current record and
         // ask how many records to move.
         strCommand = "Record:\t\t"+ rstAuthors.getAbsolutePosition() + 
            " of " + rstAuthors.getRecordCount() + "\n" + "\tAuthor:\t\t"
             + rstAuthors.getField("au_fname").getString() + 
             " " + rstAuthors.getField("au_lname").getString() + 
            "\n" +"\tLocation:\t" + 
            rstAuthors.getField("city").getString() +
             ", " +rstAuthors.getField("state").getString()
             +"\n\n"+"\tEnter number of records to move" +
            " (positive or negative).";

         System.out.print("\t"+ strCommand + "\t");
         line =in.readLine();

         // No entry exits program loop.
         if (line.length()== 0)
            break;

         // Converts string entry to int.
         lngMove = Integer.parseInt(line);

         // Store bookmark in case the move goes too far
         // forward or backward.
         varBookmark =(Variant)rstAuthors.getBookmark();

         // Move method requires parameter of data type int.
         rstAuthors.move(lngMove);

         // Trap for BOF and EOF.
         if (rstAuthors.getBOF())
         {
            System.out.println("\tToo far backward!  " +
               "Returning to the current record.");
            rstAuthors.setBookmark(varBookmark);
         }
         if (rstAuthors.getEOF())
         {
            System.out.println("\tToo far forward!  " +
               "Returning to the current record.");
            rstAuthors.setBookmark(varBookmark);
         }
      }
      // Cleanup objects before exit.
      rstAuthors.close();
      System.out.println("\tPress <Enter> to continue..");
      in.readLine();
   }

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

      // As passing a recordset, check for null pointer.
      if (rstAuthors!=null)
      {
         PrintProviderError(rstAuthors.getActiveConnection());
      }
      else
      {
         System.out.println(" Exception: "+ ae.getMessage());
      }
   }
   // System Read requires this catch.
   catch(java.io.IOException je)
   {
      PrintIOError(je);
   }
   // Required if the user enter non integer value.
   catch(java.lang.NumberFormatException ne)
   {
      System.out.println("\n\nPlease enter integer values!");
      rstAuthors.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("\tSource = " + je.getClass() + "\n");
      System.out.println("\tDescription = " + je.getMessage() + "\n");
   }
}