CacheSize Property Example (VJ++)

CacheSize Property Example (VJ++)

This example uses the CacheSize property to show the difference in performance for an operation performed with and without a 30-record cache.

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

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

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

    // CacheSizeX function

    static void CacheSizeX()
    {

        // Define ADO Objects.
        Recordset rstRoySched = null;

        // Declarations.
        BufferedReader in =
            new BufferedReader (new InputStreamReader(System.in));
        String line = null;
        String strCnn = "Provider=sqloledb;Data Source=srv;"
            + "Initial Catalog=Pubs;User Id=sa;Password=;";

        long timeStart;
        long timeEnd;
        float timeNoCache;
        float timeCache;
        int   intLoop;
        String strTemp;

        try
        {
            // Open the RoySched table.
            rstRoySched = new Recordset();
            rstRoySched.open("roysched", strCnn,
                AdoEnums.CursorType.FORWARDONLY,
                AdoEnums.LockType.READONLY,
                AdoEnums.CommandType.TABLE);

            // Enumerate the Recordset object twice and record
            // the elapsed time.

            timeStart = System.currentTimeMillis();
            for ( intLoop = 0; intLoop < 2; intLoop++)
            {
                rstRoySched.moveFirst();
                while (!rstRoySched.getEOF())
                {
                    // Execute a simple operation for the
                    // performance test.
                    strTemp = rstRoySched.getField("title_id").getString();
                    rstRoySched.moveNext();
                }

            }

            timeEnd = System.currentTimeMillis();
            timeNoCache =(float)(timeEnd - timeStart)/1000f;

            // Cache records in groups of 30 records.
            rstRoySched.moveFirst();
            rstRoySched.setCacheSize(30);
            timeStart = System.currentTimeMillis();

            // Enumerate the Recordset object twice and record
            // the elapsed time.
            for ( intLoop = 0; intLoop < 2; intLoop++)
            {
                rstRoySched.moveFirst();
                while (!rstRoySched.getEOF())
                {
                    // Execute a simple operation for the
                    // performance test.

                    strTemp = rstRoySched.getField("title_id").getString();
                    rstRoySched.moveNext();
                }

            }

            timeEnd = System.currentTimeMillis();
            timeCache = (float)(timeEnd - timeStart)/1000f;

            // Display performance results.
            System.out.println("\nCaching Performance Results:");
            System.out.println("\n\tNo Cache: " + timeNoCache + " seconds");
            System.out.println("\n\t30-record cache: " + timeCache +
                " seconds");
            System.out.println("\n\nPress <Enter> to continue..");
            in.readLine();

            // Cleanup objects before exit.
            rstRoySched.close();

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

            // Check for null pointer for connection object.
            if (rstRoySched.getActiveConnection()==null)
                System.out.println("Exception: " + ae.getMessage());

            // As passing a Recordset, check for null pointer first.
            if (rstRoySched != null)
            {
                PrintProviderError(rstRoySched.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");
    }
}