MDAC 2.5 SDK - ADO

Sort Property Example (VJ++)

See Also

This example uses the Recordset object's Sort property to reorder the rows of a Recordset derived from the Authors table of the Pubs database. A secondary utility routine prints each row.

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

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

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

   // SortX function

   static void SortX()
   {
      // Define ADO Objects.
      Connection cnConn1 = null;
      Recordset rstAuthors = null;

      // Declarations.
      String strCnn = "DSN=Pubs;Provider=MSDASQL;uid=sa;pwd=;";

      try
      {
         cnConn1 = new Connection();
         cnConn1.open(strCnn);
         rstAuthors = new Recordset();
         rstAuthors.setCursorLocation(AdoEnums.CursorLocation.CLIENT);
         rstAuthors.open("SELECT * FROM Authors",
               cnConn1,
               AdoEnums.CursorType.STATIC,
               AdoEnums.LockType.READONLY,
               AdoEnums.CommandType.TEXT);
         SortXprint("Initial Order",rstAuthors);

         rstAuthors.setSort("au_lname ASC, au_fname ASC");
         SortXprint("Last Name Ascending",rstAuthors);

         rstAuthors.setSort("au_lname DESC, au_fname ASC");
         SortXprint("Last Name Descending",rstAuthors);

         // Cleanup objects before exit.
         rstAuthors.close();
         cnConn1.close();
      }
      catch( AdoException ae )
      {
         // Notify user of any errors that result from ADO.

         // As passing a Recordset, check for null pointer first.
         if (rstAuthors != null)
         {
            PrintProviderError(rstAuthors.getActiveConnection());
         }
         else
         {
            System.out.println("Exception: " + ae.getMessage());
         }
      }

   }

   // SortXprint function

   static void SortXprint(String strTitle,Recordset rstp)
   {
      // Declarations.
      BufferedReader in = 
         new BufferedReader (new InputStreamReader(System.in));
      int intDisplaysize = 15;
      int intCount = 1;
      try
      {
         System.out.println("---------------" +
                        strTitle +
                        "---------------");
         System.out.println("First Name   Last Name" + "\n" +
                        "-------------------------" +
                        "-------------------------");
         rstp.moveFirst();
         while(!rstp.getEOF())
         {
            System.out.println(rstp.getField("au_fname").getString() +
                           "   " +
                           rstp.getField("au_lname").getString());
            if(intCount % intDisplaysize == 0)
            {
               System.out.println("\nPress <Enter> to continue..");
               in.readLine();
               intCount = 0;
            }
            intCount++;
            rstp.moveNext();
         }
         System.out.println("\nPress <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 first.
         if (rstp != null)
         {
            PrintProviderError(rstp.getActiveConnection());
         }
         else
         {
            System.out.println("Exception: " + ae.getMessage());
         }
      }

      // System read requires this catch.
      catch( java.io.IOException je)
      {
         PrintIOError(je);
      }
   }
   // 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");
   }
}