WEB开发网
开发学院软件开发Java 读写混合的数据类型 阅读

读写混合的数据类型

 2007-12-23 12:29:17 来源:WEB开发网   
核心提示:import javax.microedition.rms.*;import javax.microedition.midlet.*;import javax.microedition.lcdui.*;import java.io.*;public class WriteReadMixedDataTypesExampl
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);
    }
   } 
  }
 }
}

(出处:http://www.cncms.com)


Tags:读写 混合 数据

编辑录入:爽爽 [复制链接] [打 印]
赞助商链接