Find Method Example (VJ++)

Find Method Example (VJ++)

This example uses the Recordset object's Find method to locate and count the number of business titles in the Pubs database. The example assumes the underlying provider does not support similar functionality.

// The WFC class includes the ADO objects.
import com.ms.wfc.data.*;
import java.io.* ;
import com.ms.com.*;

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

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

    // FindX function

    static void FindX()
    {

        // Define ADO Objects.
        Connection cnConn1 = null;
        Recordset rstTitles = null;

        // Declarations.
        BufferedReader in = 
            new BufferedReader (new InputStreamReader(System.in));
        String strCnn = "DSN=Pubs;Provider=MSDASQL;uid=sa;pwd=;";
        Variant varMark = null;
        int intCount = 0;

        try
        {
            cnConn1 = new Connection();
            cnConn1.open(strCnn);
            rstTitles = new Recordset();
            rstTitles.open("SELECT title_id FROM titles",
                    cnConn1,
                    AdoEnums.CursorType.STATIC,
                    AdoEnums.LockType.READONLY,
                    AdoEnums.CommandType.TEXT);

            //  The default parameters are sufficient to search forward
            //  through a Recordset.
            rstTitles.find("title_id LIKE 'BU%'");

            // Skip current record to avoid finding the same row repeatedly.
            // The bookmark is redundant because Find searches from current
            // position.
            while(!rstTitles.getEOF()) // Continue if last find succeeded.
            {
                System.out.println("Title ID: "
                                   + rstTitles.getField("title_id").getString());
                intCount++; // Count the last title found.
                varMark = (Variant)rstTitles.getBookmark(); 
                // Note current position.
                rstTitles.find("title_id LIKE 'BU%'",
                         1,
                         AdoEnums.SearchDirection.FORWARD,
                         varMark);
            }

            // Cleanup objects before exit.
            rstTitles.close();
            cnConn1.close();

            System.out.println("\nThe number of business titles is " +
                               Integer.toString(intCount));
            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 (rstTitles != null)
            {
                PrintProviderError(rstTitles.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");
    }
}