Open and Close Methods Example (VJ++)

Open and Close Methods Example (VJ++)

This example uses the Open and Close methods on both Recordset and Connection objects that have been opened.

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

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

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

    // OpenX function

    static void OpenX()
    {

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

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

        try
        {
            // Open connection.
            cnConn1 = new Connection();
            cnConn1.open(strCnn);

            // Open Employees table.
            rstEmployees = new Recordset();
            rstEmployees.setCursorType(AdoEnums.CursorType.KEYSET);
            rstEmployees.setLockType(AdoEnums.LockType.OPTIMISTIC);
            rstEmployees.open("Employees", cnConn1,
                          AdoEnums.CursorType.KEYSET,
                          AdoEnums.LockType.OPTIMISTIC,
                          AdoEnums.CommandType.TABLE);

            // Assign the first employee record's hire date
            // to a variable, then change the hire date.
            varDate = rstEmployees.getField("hire_date").getOriginalValue();
            System.out.println("Original data\n");
            System.out.println("\tName - Hire Date");
            strHDate = rstEmployees.getField("hire_date").getString();
            strHDate = strHDate.substring(5,7) + "/" + 
                strHDate.substring(8,10)
                 + "/" + strHDate.substring(2,4);
            System.out.println("\t" + 
                rstEmployees.getField("fName").getString()+ " "
                 + rstEmployees.getField("lName").getString()+ " - "
                 + strHDate);
            System.out.println("\nPress <Enter> to continue..");
            in.readLine();
            rstEmployees.getField("hire_date").setString("1/1/1900");
            rstEmployees.update();
            System.out.println("Changed data\n");
            System.out.println("\tName - Hire Date");
            strHDate = rstEmployees.getField("hire_date").getString();
            strHDate = strHDate.substring(5,7) + "/" + 
                strHDate.substring(8,10)
                 + "/" + strHDate.substring(0,4);
            System.out.println("\t" + 
                rstEmployees.getField("fName").getString()+ " "
                 + rstEmployees.getField("lName").getString()+ " - "
                 + strHDate);
            System.out.println("\nPress <Enter> to continue..");
            in.readLine();

            // Requery Recordset and reset the hire date.
            rstEmployees.requery();
            rstEmployees.getField("hire_date").setValue(varDate);
            rstEmployees.update();
            System.out.println("Data after reset\n");
            System.out.println("\tName - Hire Date");
            strHDate = rstEmployees.getField("hire_date").getString();
            strHDate = strHDate.substring(5,7) + "/" + 
                strHDate.substring(8,10)
                 + "/" + strHDate.substring(2,4);
            System.out.println("\t" + 
                rstEmployees.getField("fName").getString()+ " "
                 + rstEmployees.getField("lName").getString()+ " - "
                 + strHDate);
            System.out.println("\nPress <Enter> to continue..");
            in.readLine();

            // Cleanup objects before exit.
            rstEmployees.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 (rstEmployees != null)
            {
                PrintProviderError(rstEmployees.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");
    }
}