i have the following problem. This midlet works fine when i execute it in the emulator, but when i upload it to my motorola i290 (with nextel company), and i start it, it freezes. So never starts (the program starts doing a request to a php page)
Here is the code, if anyone knows why my program work fine in the Wireless Toolkit emulator and not in the phone, please let me know. Thanks
This is my "Connection" method
String getGrade(String url) throws IOException {
HttpConnection c = null;
InputStream is = null;
OutputStream os = null;
StringBuffer b = new StringBuffer();
TextBox t = null;
int x = 5, y =7;
try {
c = (HttpConnection)Connector.open(url,Connector.READ,true);
c.setRequestMethod(HttpConnection.GET);
c.setRequestProperty("IF-Modified-Since", "10 Nov 2000 17:29:12 GMT");
c.setRequestProperty("User-Agent","Profile/MIDP-2.0 Confirguration/CLDC-1.1");
c.setRequestProperty("Content-Language", "en-CA");
os = c.openOutputStream();
is = c.openDataInputStream();
int ch;
while ((ch = is.read()) != -1) {
b.append((char) ch);
System.out.println((char)ch);
}
t = new TextBox("Final Grades", b.toString(), 1024, 0);
} finally {
if(is!= null) {
is.close();
}
if(os != null) {
os.close();
}
if(c != null) {
c.close();
}
}
//display.setCurrent(t);
return b.toString();
}
I had the same issue with Sony Ericsson and what i found out is that there URL is sometime truncated when its too long. Try USING POST Instead
c = (HttpConnection) Connector.open(serverURL, 3);
c.setRequestProperty("IF-Modified-Since", "20 Jan 2001 16:19:14 GMT");
c.setRequestProperty("User-Agent", "Profile/MIDP-1.0 Configuration/CLDC-1.0");
c.setRequestProperty("Content-Language", "en-US");
c.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
c.setRequestProperty("Content-Length", packet.getSentLength());
c.setRequestProperty("Cache-Control", "no-store no-cache");
c.setRequestProperty("Pragma", "no-cache");
c.setRequestMethod(HttpConnection.POST);
c.setRequestProperty("Content-Length", packet.getSentLength());
out = c.openOutputStream();
if (out != null) {
out.write(packet.getSentBytes());
}
is = c.openInputStream();
hcCode = c.getResponseCode();
This worked for me ..... Note Change packet to the relevant information
Related
I'm trying to download an Excel in a liferay portlet but when I'm going to get the outPutPortletStream I obtain the next exception:
java.lang.IllegalStateException: Unable to obtain OutputStream because Writer is already in use
This is the method I'm using to download the Excel:
public static void descargaFichero(ResourceRequest resourceRequest, ResourceResponse resourceResponse) throws Exception {
HttpServletRequest request = PortalUtil.getOriginalServletRequest(PortalUtil.getHttpServletRequest(resourceRequest));
OutputStreamWriter osWriter = null;
BufferedWriter bWriter = null;
OutputStream outputStream = null;
InputStream is = null;
InputStreamReader isr = null;
File tempFile = null;
try {
String idDescarga = request.getParameter("id-descarga");
String rutaFicheroDescarga = Encriptador.decrypt(ConstantesFlujos.CLAVE_ENCRIPTADO_JSON, idDescarga);
String extension = FileUtil.getExtension(rutaFicheroDescarga);
String nombreArchivo = String.format("%s%s.%s",
ConstantesFlujos.PREFIJO_NOMBRE_FICHERO_RENOVACION,
fechaDesglosada(),
extension);
if(GestorLog.isInfoEnabled(clase)){
GestorLog.info(clase, String.format("Descargando fichero temporal: '%s' a '%s'", rutaFicheroDescarga, nombreArchivo));
}
if (extension.equalsIgnoreCase("xls")) {
resourceResponse.setContentType("application/vnd.ms-excel");
} else {
resourceResponse.setContentType("application/octet-stream");
}
((PortletResponse) resourceResponse).addProperty("Content-disposition", String.format("atachment; filename=%s", nombreArchivo));
tempFile = new File(rutaFicheroDescarga);
outputStream = resourceResponse.getPortletOutputStream();
osWriter = new OutputStreamWriter(outputStream, "ISO-8859-1");
char[] buf = new char[8192];
is = new FileInputStream(tempFile);
isr = new InputStreamReader(is, "ISO-8859-1");
int c = 0;
while ((c = isr.read(buf, 0, buf.length)) > 0) {
osWriter.write(buf, 0, c);
osWriter.flush();
}
} catch(Exception e){
GestorLog.error(clase, "Error en el metodo descargaFichero: " + e.getMessage());
throw e;
} finally {
if (isr != null) {
isr.close();
}
if (is != null) {
is.close();
}
if (bWriter != null) {
bWriter.close();
}
if (outputStream != null) {
outputStream.close();
}
if (tempFile != null) {
tempFile.delete();
}
}
}
And I get the error in the line:
outputStream = resourceResponse.getPortletOutputStream();
This might be due to resourceResponse.addProperty being called before accessing the stream. Those operations can be nasty, as two parties will now try to write data to the output.
An easy way to omit all problems is to just delegate it all to the portal: PortletResponseUtil.sendFile exists in a couple of different variations, e.g.
PortletResponseUtil.sendFile(
resourceRequest,
resourceResponse,
fileName,
inputStream,
contentLength,
contentType,
contentDispositionType); // e.g. HttpHeaders.CONTENT_DISPOSITION_ATTACHMENT
I followed this NAudio Demo modified to play ShoutCast.
In my full code I have to resample the incoming audio and stream it again over the network to a network player. Since I get many "clicks and pops", I came back to the demo code and I found that these artifacts are originated after the decoding block.
If I save the incoming stream in mp3 format, it is pretty clear.
When I save the raw decoded data (without other processing than the decoder) I get many audio artifacts.
I wonder whether I am doing some error, even if my code is almost equal to the NAudio demo.
Here the function from the example as modified by me to save the raw data. It is called as a new Thread.
private void StreamMP3(object state)
{
//Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
//SettingsSection section = (SettingsSection)config.GetSection("system.net/settings");
this.fullyDownloaded = false;
string url = "http://icestreaming.rai.it/5.mp3";//(string)state;
webRequest = (HttpWebRequest)WebRequest.Create(url);
int metaInt = 0; // blocksize of mp3 data
int framesize = 0;
webRequest.Headers.Clear();
webRequest.Headers.Add("GET", "/ HTTP/1.0");
// needed to receive metadata informations
webRequest.Headers.Add("Icy-MetaData", "1");
webRequest.UserAgent = "WinampMPEG/5.09";
HttpWebResponse resp = null;
try
{
resp = (HttpWebResponse)webRequest.GetResponse();
}
catch (WebException e)
{
if (e.Status != WebExceptionStatus.RequestCanceled)
{
ShowError(e.Message);
}
return;
}
byte[] buffer = new byte[16384 * 4]; // needs to be big enough to hold a decompressed frame
try
{
// read blocksize to find metadata block
metaInt = Convert.ToInt32(resp.GetResponseHeader("icy-metaint"));
}
catch
{
}
IMp3FrameDecompressor decompressor = null;
byteOut = createNewFile(destPath, "salva", "raw");
try
{
using (var responseStream = resp.GetResponseStream())
{
var readFullyStream = new ReadFullyStream(responseStream);
readFullyStream.metaInt = metaInt;
do
{
if (mybufferedWaveProvider != null && mybufferedWaveProvider.BufferLength - mybufferedWaveProvider.BufferedBytes < mybufferedWaveProvider.WaveFormat.AverageBytesPerSecond / 4)
{
Debug.WriteLine("Buffer getting full, taking a break");
Thread.Sleep(500);
}
else
{
Mp3Frame frame = null;
try
{
frame = Mp3Frame.LoadFromStream(readFullyStream, true);
if (metaInt > 0)
UpdateSongName(readFullyStream.SongName);
else
UpdateSongName("No Song Info in Stream...");
}
catch (EndOfStreamException)
{
this.fullyDownloaded = true;
// reached the end of the MP3 file / stream
break;
}
catch (WebException)
{
// probably we have aborted download from the GUI thread
break;
}
if (decompressor == null)
{
// don't think these details matter too much - just help ACM select the right codec
// however, the buffered provider doesn't know what sample rate it is working at
// until we have a frame
WaveFormat waveFormat = new Mp3WaveFormat(frame.SampleRate, frame.ChannelMode == ChannelMode.Mono ? 1 : 2, frame.FrameLength, frame.BitRate);
decompressor = new AcmMp3FrameDecompressor(waveFormat);
this.mybufferedWaveProvider = new BufferedWaveProvider(decompressor.OutputFormat);
this.mybufferedWaveProvider.BufferDuration = TimeSpan.FromSeconds(200); // allow us to get well ahead of ourselves
framesize = (decompressor.OutputFormat.Channels * decompressor.OutputFormat.SampleRate * (decompressor.OutputFormat.BitsPerSample / 8) * 20) / 1000;
//this.bufferedWaveProvider.BufferedDuration = 250;
}
int decompressed = decompressor.DecompressFrame(frame, buffer, 0);
//Debug.WriteLine(String.Format("Decompressed a frame {0}", decompressed));
mybufferedWaveProvider.AddSamples(buffer, 0, decompressed);
while (mybufferedWaveProvider.BufferedDuration.Milliseconds >= 20)
{
byte[] read = new byte[framesize];
mybufferedWaveProvider.Read(read, 0, framesize);
byteOut.Write(read, 0, framesize);
}
}
} while (playbackState != StreamingPlaybackState.Stopped);
Debug.WriteLine("Exiting");
// was doing this in a finally block, but for some reason
// we are hanging on response stream .Dispose so never get there
decompressor.Dispose();
}
}
finally
{
if (decompressor != null)
{
decompressor.Dispose();
}
}
}
OK i found the problem. I included the shoutcast metadata to the MP3Frame.
See the comment "HERE I COLLECT THE BYTES OF THE MP3 FRAME" to locate the correct point to get the MP3 frame with no streaming metadata.
The following code runs without audio artifacts:
private void SHOUTcastReceiverThread()
{
//-*- String server = "http://216.235.80.18:8285/stream";
//String serverPath = "/";
//String destPath = "C:\\temp\\"; // destination path for saved songs
HttpWebRequest request = null; // web request
HttpWebResponse response = null; // web response
int metaInt = 0; // blocksize of mp3 data
int count = 0; // byte counter
int metadataLength = 0; // length of metadata header
string metadataHeader = ""; // metadata header that contains the actual songtitle
string oldMetadataHeader = null; // previous metadata header, to compare with new header and find next song
//CircularQueueStream framestream = new CircularQueueStream(2048);
QueueStream framestream = new QueueStream();
framestream.Position = 0;
bool bNewSong = false;
byte[] buffer = new byte[512]; // receive buffer
byte[] dec_buffer = new byte[decSIZE];
Mp3Frame frame;
IMp3FrameDecompressor decompressor = null;
Stream socketStream = null; // input stream on the web request
// create web request
request = (HttpWebRequest)WebRequest.Create(server);
// clear old request header and build own header to receive ICY-metadata
request.Headers.Clear();
request.Headers.Add("GET", serverPath + " HTTP/1.0");
request.Headers.Add("Icy-MetaData", "1"); // needed to receive metadata informations
request.UserAgent = "WinampMPEG/5.09";
// execute request
try
{
response = (HttpWebResponse)request.GetResponse();
}
catch (Exception ex)
{
Console.WriteLine(ex.Message);
return;
}
// read blocksize to find metadata header
metaInt = Convert.ToInt32(response.GetResponseHeader("icy-metaint"));
try
{
// open stream on response
socketStream = response.GetResponseStream();
var readFullyStream = new ReadFullyStream(socketStream);
frame = null;
// rip stream in an endless loop
do
{
if (IsBufferNearlyFull)
{
Debug.WriteLine("Buffer getting full, taking a break");
Thread.Sleep(500);
frame = null;
}
else
{
int bufLen = readFullyStream.Read(buffer, 0, buffer.Length);
try
{
if (framestream.CanRead && framestream.Length > 512)
frame = Mp3Frame.LoadFromStream(framestream);
else
frame = null;
}
catch (Exception ex)
{
frame = null;
}
if (bufLen < 0)
{
Debug.WriteLine("Buffer error 1: exit.");
return;
}
// processing RAW data
for (int i = 0; i < bufLen; i++)
{
// if there is a header, the 'headerLength' would be set to a value != 0. Then we save the header to a string
if (metadataLength != 0)
{
metadataHeader += Convert.ToChar(buffer[i]);
metadataLength--;
if (metadataLength == 0) // all metadata informations were written to the 'metadataHeader' string
{
string fileName = "";
string fileNameRaw = "";
// if songtitle changes, create a new file
if (!metadataHeader.Equals(oldMetadataHeader))
{
// flush and close old byteOut stream
if (byteOut != null)
{
byteOut.Flush();
byteOut.Close();
byteOut = null;
}
if (byteOutRaw != null)
{
byteOutRaw.Flush();
byteOutRaw.Close();
byteOutRaw = null;
}
timeStart = timeEnd;
// extract songtitle from metadata header. Trim was needed, because some stations don't trim the songtitle
//fileName = Regex.Match(metadataHeader, "(StreamTitle=')(.*)(';StreamUrl)").Groups[2].Value.Trim();
fileName = Regex.Match(metadataHeader, "(StreamTitle=')(.*)(';)").Groups[2].Value.Trim();
// write new songtitle to console for information
if (fileName.Length == 0)
fileName = "shoutcast_test";
fileNameRaw = fileName + "_raw";
framestream.reSetPosition();
SongChanged(this, metadataHeader);
bNewSong = true;
// create new file with the songtitle from header and set a stream on this file
timeEnd = DateTime.Now;
if (bWrite_to_file)
{
byteOut = createNewFile(destPath, fileName, "mp3");
byteOutRaw = createNewFile(destPath, fileNameRaw, "raw");
}
timediff = timeEnd - timeStart;
// save new header to 'oldMetadataHeader' string, to compare if there's a new song starting
oldMetadataHeader = metadataHeader;
}
metadataHeader = "";
}
}
else // write mp3 data to file or extract metadata headerlength
{
if (count++ < metaInt) // write bytes to filestream
{
//HERE I COLLECT THE BYTES OF THE MP3 FRAME
framestream.Write(buffer, i, 1);
}
else // get headerlength from lengthbyte and multiply by 16 to get correct headerlength
{
metadataLength = Convert.ToInt32(buffer[i]) * 16;
count = 0;
}
}
}//for
if (bNewSong)
{
decompressor = createDecompressor(frame);
bNewSong = false;
}
if (frame != null && decompressor != null)
{
framedec(decompressor, frame);
}
// fine Processing dati RAW
}//Buffer is not full
SHOUTcastStatusProcess();
} while (playbackState != StreamingPlaybackState.Stopped);
} //try
catch (Exception ex)
{
Console.WriteLine(ex.Message);
}
finally
{
if (byteOut != null)
byteOut.Close();
if (socketStream != null)
socketStream.Close();
if (decompressor != null)
{
decompressor.Dispose();
decompressor = null;
}
if (null != request)
request.Abort();
if (null != framestream)
framestream.Dispose();
if (null != bufferedWaveProvider)
bufferedWaveProvider.ClearBuffer();
//if (null != bufferedWaveProviderOut)
// bufferedWaveProviderOut.ClearBuffer();
if (null != mono16bitFsinStream)
{
mono16bitFsinStream.Close();
mono16bitFsinStream.Dispose();
}
if (null != middleStream2)
{
middleStream2.Close();
middleStream2.Dispose();
}
if (null != resampler)
resampler.Dispose();
}
}
public class QueueStream : MemoryStream
{
long ReadPosition = 0;
long WritePosition = 0;
public QueueStream() : base() { }
public override int Read(byte[] buffer, int offset, int count)
{
Position = ReadPosition;
var temp = base.Read(buffer, offset, count);
ReadPosition = Position;
return temp;
}
public override void Write(byte[] buffer, int offset, int count)
{
Position = WritePosition;
base.Write(buffer, offset, count);
WritePosition = Position;
}
public void reSetPosition()
{
WritePosition = 0;
ReadPosition = 0;
Position = 0;
}
}
private void framedec(IMp3FrameDecompressor decompressor, Mp3Frame frame)
{
int Ndecoded_samples = 0;
byte[] dec_buffer = new byte[decSIZE];
Ndecoded_samples = decompressor.DecompressFrame(frame, dec_buffer, 0);
bufferedWaveProvider.AddSamples(dec_buffer, 0, Ndecoded_samples);
NBufferedSamples += Ndecoded_samples;
brcnt_in.incSamples(Ndecoded_samples);
if (Ndecoded_samples > decSIZE)
{
Debug.WriteLine(String.Format("Too many samples {0}", Ndecoded_samples));
}
if (byteOut != null)
byteOut.Write(frame.RawData, 0, frame.RawData.Length);
if (byteOutRaw != null) // as long as we don't have a songtitle, we don't open a new file and don't write any bytes
byteOutRaw.Write(dec_buffer, 0, Ndecoded_samples);
frame = null;
}
private IMp3FrameDecompressor createDecompressor(Mp3Frame frame)
{
IMp3FrameDecompressor dec = null;
if (frame != null)
{
// don't think these details matter too much - just help ACM select the right codec
// however, the buffered provider doesn't know what sample rate it is working at
// until we have a frame
WaveFormat srcwaveFormat = new Mp3WaveFormat(frame.SampleRate, frame.ChannelMode == ChannelMode.Mono ? 1 : 2, frame.FrameLength, frame.BitRate);
dec = new AcmMp3FrameDecompressor(srcwaveFormat);
bufferedWaveProvider = new BufferedWaveProvider(dec.OutputFormat);// decompressor.OutputFormat
bufferedWaveProvider.BufferDuration = TimeSpan.FromSeconds(400); // allow us to get well ahead of ourselves
// ------------------------------------------------
//Create an intermediate format with same sampling rate, 16 bit, mono
middlewavformat = new WaveFormat(dec.OutputFormat.SampleRate, 16, 1);
outwavFormat = new WaveFormat(Fs_out, 16, 1);
// wave16ToFloat = new Wave16ToFloatProvider(provider); // I have tried with and without this converter.
wpws = new WaveProviderToWaveStream(bufferedWaveProvider);
//Check middlewavformat.Encoding == WaveFormatEncoding.Pcm;
mono16bitFsinStream = new WaveFormatConversionStream(middlewavformat, wpws);
middleStream2 = new BlockAlignReductionStream(mono16bitFsinStream);
resampler = new MediaFoundationResampler(middleStream2, outwavFormat);
}
return dec;
}
I have my application playing the radio stream which is shoutcast streaming. I have searched on the internet for 2 days but my application stills can't play this url. I don't know how to solve this.
This is my sample source code.
String url1 = "http://203.150.224.142:8003/;
HttpConnection con= (HttpConnection)Connector.open(url1);
InputStream is = con.openInputStream();
player = Manager.createPlayer(is, "audio/mpeg");
player.realize();
player.prefetch();
player.start();
I have used this code in production, it should work for you also.
HttpConnection conn = (HttpConnection) Connector.open(music.getTrack_url() + "?streamable=true", Connector.READ_WRITE);
if (conn.getResponseCode() == HttpConnection.HTTP_OK) {
is = conn.openInputStream();
player = Manager.createPlayer(is, "audio/mp3");
player.addPlayerListener(thisObj);
player.realize();
player.prefetch();
player.start();
}
Try This.
public void loadShoutcast(String url)
{
StreamConnection connection = null;
int BUFFER_SIZE = 1024;
DataOutputStream dos_ = null;
OutputStream os_ = null;
try
{
System.out.println("opening connection " + url);
//Shoutcast URL
connection = (StreamConnection) Connector.open(url);
os_ = connection.openOutputStream();
dos_ = new DataOutputStream(os_);
// send the HTTP request
String req = "GET / HTTP/1.1\r\nUser-Agent: Profile/MIDP-1.0 Configuration/CLDC-1.0\r\n\r\n";
dos_.write(req.getBytes());
is = null;
is = connection.openInputStream();
long byteDone = 0;
int byteCount;
byte[] buffer = new byte[BUFFER_SIZE];
//Connection to file where you want to save the content of shoutcast radio
//It can be skipped in case you dont want to save the contents
out = tempFilecon.openDataOutputStream();
System.out.println("starting download");
while (byteCount = is.read(buffer)) >= 0)
{
out.write(buffer, 0, byteCount);
byteDone += byteCount;
done += byteCount;
}
return;
}
catch (InterruptedIOException e)
{
System.out.println("InterruptedIOException 1" + e.getMessage());
return;
}
catch (Exception e)
{
System.out.println("ERROR - 51 " + e.getMessage());
return;
}
finally
{
if (dos_ != null)
{
dos_.close();
dos_ = null;
}
if (os_ != null)
{
os_.close();
os_ = null;
}
if (is != null)
{
is.close();
is = null;
}
if (out != null)
{
out.close();
out = null;
}
System.out.println("closing connection");
if (connection != null)
{
connection.close();
connection = null;
}
}
// return false;
}
i have created an application in J2ME that uses the following method to connect to a server. php is used on the Server side to process the requests. the application works fine on some phones like NOkia asha 303 but throws IOException on other phones what could be the problem with this code. this method is called on a different thread. i also want to ask if you use post in j2me and set the
httpConn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
do you have to urlencode the data before sending or that is handled automatically by j2me
public String sendData(String serverUrl, String dataToSend) {
String strResponse = "0"; //string to hold serverResponse
StringBuffer sb = new StringBuffer("");
HttpConnection httpConn = null;
InputStream inputStream = null;
OutputStream outStream = null;
try {
//convert the dataToSend to bytes
String strData = dataToSend; // get the data to Send and store it in a variable.
byte[] dataToSendBytes = strData.getBytes();
//open the Connection to the server.
httpConn = (HttpConnection) Connector.open(serverUrl, Connector.READ_WRITE, true);
if (httpConn != null) {
httpConn.setRequestMethod(HttpConnection.POST); // method used to send the data.
httpConn.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
httpConn.setRequestProperty("User-Agent", "Profile/MIDP-2.0 Configuration/CLDC-1.1");
//httpConn.setRequestProperty("Content-Language", "en-US"); //language to use.
//setRequestProperty("Connection", "close") ===> could generate or Solve IOExceptions on different mobile Phones.
//httpConn.setRequestProperty("Connection", "close");
//setting the Content-length could have issues with some Servers===>
//if the dataToSend is Empty String => contentLen = 0 , else get length of the dataBytes.
String contentLen = ((dataToSend.length() > 0) ? Integer.toString(dataToSendBytes.length) : Integer.toString(0));
//httpConn.setRequestProperty("Content-length", contentLen); //not working on Emulator ....enable on shipping application.
//open the output Stream to send data to the Server.
outStream = httpConn.openOutputStream();
// send the bytes of data to the Server.===>
//outStream.write(dataToSendBytes);
//send the data bytes to the Server.
int byteLen = dataToSendBytes.length; //length of byteToSend.
for (int k = 0; k < byteLen; k++) {
//send all the databytes to the Server.
outStream.write(dataToSendBytes[k]);
}
//close the outputStream ===immediately after sending the data bytes to the Server===>eliminates the IOExceptions.
closeOutStream(outStream);
//get response code on Sending Data===> getting response code automatically flushes the output data.
ntworkResponseCode = httpConn.getResponseCode();
if (ntworkResponseCode == HttpConnection.HTTP_OK) {
//connection to the Server was okay.
if (httpConn != null) {
//read the Response From the Server-----------
inputStream = httpConn.openInputStream(); // open the inputStream.
//get server Response Content length.
int contLen = (int) httpConn.getLength();
byte[] serverResponseBytes; //byte array to store the serverResponse.
if (contLen != -1) {
//store the serverResponse to a byte array.===> using a byte buffer could be faster.
serverResponseBytes = new byte[contLen];
inputStream.read(serverResponseBytes);
//convert the bytes to String and store them to the StringBuffer.
sb.append(new String(serverResponseBytes));
} else {
//serverResponse Length not available===> read character by character could be slower.
int read;
while ((read = inputStream.read()) != -1) {
sb.append((char) read);
}
}
//store the server response in a String.
strResponse = sb.toString();
}
} else {
//connection problem occured.
//throw new IOException("Http Response Code [" + ntworkResponseCode + "]");
}
}// the httpConnection Not null.--end.
} catch (IllegalArgumentException arge) {
strResponse = CONNECTION_EXCEPTION;
} catch (ConnectionNotFoundException cone) {
//a string to show we got an exception
strResponse = CONNECTION_EXCEPTION;
} catch (IOException ioe) {
//a string to show we got an exception
strResponse = CONNECTION_EXCEPTION;
} catch (SecurityException se) {
//user cancelled the Connection Request.
strResponse = CONNECTION_EXCEPTION;
} finally {
//close all the connection streams
try {
if (inputStream != null) {
//close the inputStream
inputStream.close();
inputStream = null;
}
if (outStream != null) {
//close the outStream.
outStream.close();
outStream = null;
}
if (httpConn != null) {
//close the connection object.
httpConn.close();
httpConn = null;
}
} catch (IOException ie) {
//show exception occured.
}
}
//return server Response to the Client.
return strResponse;
}
I am developing an j2me application which is communicating with the database using servlet.
I want to store the data received from servlet into record store and display it.how this can be achieved?Please provide code examples.
Thank you in advance
public void viewcon()
{
StringBuffer sb = new StringBuffer();
try {
HttpConnection c = (HttpConnection) Connector.open(url);
c.setRequestProperty("User-Agent","Profile/MIDP-1.0, Configuration/CLDC-1.0");
c.setRequestProperty("Content-Language","en-US");
c.setRequestMethod(HttpConnection.POST);
DataOutputStream os = (DataOutputStream)c.openDataOutputStream();
os.flush();
os.close();
// Get the response from the servlet page.
DataInputStream is =(DataInputStream)c.openDataInputStream();
//is = c.openInputStream();
int ch;
sb = new StringBuffer();
while ((ch = is.read()) != -1) {
sb.append((char)ch);
}
// return sb;
showAlert(sb.toString());//display data received from servlet
is.close();
c.close();
} catch (Exception e) {
showAlert(e.getMessage());
}
}
Put this function call where you show the response data alert
writeToRecordStore(sb.toString().getBytes());
The function definition is as below:
private static String RMS_NAME = "NETWORK-DATA-STORAGE";
private boolean writeToRecordStore(byte[] inStream) {
RecordStore rs = null;
try {
rs = RecordStore.openRecordStore(RMS_NAME, true);
if (null != rs) {
//Based on your logic either ADD or SET the record
rs.addRecord(inStream, 0, inStream.length);
return true;
} else {
return false;
}
} catch (RecordStoreException ex) {
ex.printStackTrace();
return false;
} finally {
try {
if (null != rs) {
rs.closeRecordStore();
}
} catch (RecordStoreException recordStoreException) {
} finally {
rs = null;
}
}
}
After you have saved the data, read the records store RMS-NAME and check the added index to get the response data.
.
NOTE: The assumption is the network response data is to be appended to the record store. If you want to set it to a particular record modify the method writeToRecordStore(...) accordingly.
//this code throws exception in display class.
try
{
byte[] byteInputData = new byte[5];
int length = 0;
// access all records present in record store
for (int x = 1; x <= rs.getNumRecords(); x++)
{
if (rs.getRecordSize(x) > byteInputData.length)
{
byteInputData = new byte[rs.getRecordSize(x)];
}
length = rs.getRecord(x, byteInputData, 0);
}
alert =new Alert("reading",new String(byteInputData,0,length),null,AlertType.WARNING);
alert.setTimeout(Alert.FOREVER);
display.setCurrent(alert);
}