This example shows how to enumerate mixed records in RMS.

 /*
J2ME: The Complete Reference

James Keogh

Publisher: McGraw-Hill

ISBN 0072227109

*/
//jad file (please verify the jar size)
/*
MIDlet-Name: MixedRecordEnumerationExample
MIDlet-Version: 1.0
MIDlet-Vendor: MyCompany
MIDlet-Jar-URL: MixedRecordEnumerationExample.jar
MIDlet-1: MixedRecordEnumerationExample, , 
            MixedRecordEnumerationExample
MicroEdition-Configuration: CLDC-1.0
MicroEdition-Profile: MIDP-1.0
MIDlet-JAR-SIZE: 100

*/
import javax.microedition.rms.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.io.*;

public class MixedRecordEnumerationExample 
         extends MIDlet implements CommandListener
{
  private Display display;
  private Alert alert;
  private Form form; 
  private Command exit; 
  private Command start;
  private RecordStore recordstore = null;
  private RecordEnumeration recordEnumeration = null;
  public MixedRecordEnumerationExample ()
  {
    display = Display.getDisplay(this);
    exit = new Command("Exit", Command.SCREEN, 1);
    start = new Command("Start", Command.SCREEN, 1);
    form = new Form("Mixed RecordEnumeration");
    form.addCommand(exit);
    form.addCommand(start);
    form.setCommandListener(this);
  }
  public void startApp()
  {
    display.setCurrent(form);
  }
  public void pauseApp()
  {
  }
  public void destroyApp( boolean unconditional )
  {
  }
  public void commandAction(Command command, Displayable displayable)
  {
    if (command == exit)
    {
      destroyApp(true);
      notifyDestroyed();
    }
    else if (command == start)
    {
      try
      {
        recordstore = RecordStore.openRecordStore(
                 "myRecordStore", true );
      }
      catch (Exception error)
      {
        alert = new Alert("Error Creating", 
                    error.toString(), null, AlertType.WARNING); 
        alert.setTimeout(Alert.FOREVER); 
        display.setCurrent(alert);
      }
      try
      {
        byte[] outputRecord;
        String outputString[] = {"First Record", 
                  "Second Record", "Third Record"};
        int outputInteger[] = {15, 10, 5};
        boolean outputBoolean[] = {true, false, true};    
        ByteArrayOutputStream outputStream = 
                   new ByteArrayOutputStream();
        DataOutputStream outputDataStream = 
                   new DataOutputStream(outputStream);
        for (int x = 0; x < 3; x++)
        {
          outputDataStream.writeUTF(outputString[x]);
          outputDataStream.writeBoolean(outputBoolean[x]);
          outputDataStream.writeInt(outputInteger[x]); 
          outputDataStream.flush();               
          outputRecord = outputStream.toByteArray();
          recordstore.addRecord(outputRecord, 0, 
                       outputRecord.length);
        }
        outputStream.reset();   
        outputStream.close();
        outputDataStream.close();
      }
      catch ( Exception error)
      {
        alert = new Alert("Error Writing", 
                 error.toString(), null, AlertType.WARNING); 
        alert.setTimeout(Alert.FOREVER); 
        display.setCurrent(alert);
      }
      try
      {
        StringBuffer buffer = new StringBuffer();
        byte[] byteInputData = new byte[300]; 
        ByteArrayInputStream inputStream = new ByteArrayInputStream(byteInputData);
        DataInputStream inputDataStream = 
                   new DataInputStream(inputStream);
        recordEnumeration = recordstore.enumerateRecords( 
                        null, null, false);
        while (recordEnumeration.hasNextElement())
        { 
          recordstore.getRecord(recordEnumeration.nextRecordId(), 
                byteInputData, 0);       
          buffer.append(inputDataStream.readUTF());
          buffer.append("\n");
          buffer.append(inputDataStream.readBoolean());
          buffer.append("\n");
          buffer.append(inputDataStream.readInt());
          buffer.append("\n");
          alert = new Alert("Reading", buffer.toString(), 
                   null, AlertType.WARNING);            
          alert.setTimeout(Alert.FOREVER); 
          display.setCurrent(alert); 
        }
        inputStream.close();
      }
      catch (Exception error)
      {
        alert = new Alert("Error Reading", 
               error.toString(), null, AlertType.WARNING); 
        alert.setTimeout(Alert.FOREVER); 
        display.setCurrent(alert);
      }
      try
      {
        recordstore.closeRecordStore();
      }
      catch (Exception error)
      {
        alert = new Alert("Error Closing", 
               error.toString(), null, AlertType.WARNING); 
        alert.setTimeout(Alert.FOREVER); 
        display.setCurrent(alert);
      }
      if (RecordStore.listRecordStores() != null)
      {
       try
       {
         RecordStore.deleteRecordStore("myRecordStore");
         recordEnumeration.destroy();
       }
       catch (Exception error)
       {
        alert = new Alert("Error Removing", 
                error.toString(), null, AlertType.WARNING); 
        alert.setTimeout(Alert.FOREVER); 
        display.setCurrent(alert);
       }
      }      
    }
  }     
}

 

 

 

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