Sort Property Example (VJ++)

Sort Property Example (VJ++)

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");
    }
}