WriteReadMixedDataTypesExample.java Source code

Introduction

Here is the source code for WriteReadMixedDataTypesExample.java

Source

/*
J2ME: The Complete Reference
    
James Keogh
    
Publisher: McGraw-Hill
    
ISBN 0072227109
    
*/
//jad file (please verify the jar size)
/*
MIDlet-Name: WriteReadMixedDataTypesExample
MIDlet-Version: 1.0
MIDlet-Vendor: MyCompany
MIDlet-Jar-URL: WriteReadMixedDataTypesExample.jar
MIDlet-1: WriteReadMixedDataTypesExample, , 
          WriteReadMixedDataTypesExample
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 WriteReadMixedDataTypesExample extends MIDlet implements CommandListener {
    private Display display;
    private Alert alert;
    private Form form;
    private Command exit;
    private Command start;
    private RecordStore recordstore = null;

    public WriteReadMixedDataTypesExample() {
        display = Display.getDisplay(this);
        exit = new Command("Exit", Command.SCREEN, 1);
        start = new Command("Start", Command.SCREEN, 1);
        form = new Form("Mixed Record");
        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";
                int outputInteger = 15;
                boolean outputBoolean = true;
                ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
                DataOutputStream outputDataStream = new DataOutputStream(outputStream);
                outputDataStream.writeUTF(outputString);
                outputDataStream.writeBoolean(outputBoolean);
                outputDataStream.writeInt(outputInteger);
                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 {
                String inputString = null;
                int inputInteger = 0;
                boolean inputBoolean = false;
                byte[] byteInputData = new byte[100];
                ByteArrayInputStream inputStream = new ByteArrayInputStream(byteInputData);
                DataInputStream inputDataStream = new DataInputStream(inputStream);
                for (int x = 1; x <= recordstore.getNumRecords(); x++) {
                    recordstore.getRecord(x, byteInputData, 0);
                    inputString = inputDataStream.readUTF();
                    inputBoolean = inputDataStream.readBoolean();
                    inputInteger = inputDataStream.readInt();
                    inputStream.reset();
                }
                inputStream.close();
                inputDataStream.close();
                alert = new Alert("Reading", inputString + " " + inputInteger + " " + inputBoolean, null,
                        AlertType.WARNING);
                alert.setTimeout(Alert.FOREVER);
                display.setCurrent(alert);
            } 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");
                } catch (Exception error) {
                    alert = new Alert("Error Removing", error.toString(), null, AlertType.WARNING);
                    alert.setTimeout(Alert.FOREVER);
                    display.setCurrent(alert);
                }
            }
        }
    }
}