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Using AyncTask to send a UDP packet

I am trying to send a UDP packet to a computer on the same network as my tablet. In order to do this, I began by setting up a class to hold all the appropriate objects that I need in order to create a UDP socket, create a packet, and then send that packet. This class is shown below:
public static class Session
{
public InetAddress address;
public DatagramSocket socket;
public DatagramPacket packet;
public String client;
public int port;
public byte[] receive_buffer;
public byte[] send_buffer;
public String message;
public Session (InetAddress address, DatagramSocket socket, DatagramPacket packet,
String client, int port, byte[] receive_buffer, byte[] send_buffer,
String message)
{
this.address = address;
this.socket = socket;
this.packet = packet;
this.client = client;
this.receive_buffer = receive_buffer;
this.send_buffer = send_buffer;
this.message = message;
this.port = port;
}
}
Whenever I try to send a UDP packet, I begin by creating a Session object that contains a socket, packet, message, and a few other things. I also have a Send class that I use to actually send the UDP packet. This is shown below:
public static Session Send (Session session)
{
// Execute within "try" function to catch exceptions
try
{
/* Create address*/
session.address = InetAddress.getByName(session.client);
/* Create socket */
session.socket = new DatagramSocket(session.port);
/* Create packet */
session.packet = new DatagramPacket(session.message.getBytes(),
session.message.length(), session.address, session.port);
/* Send packet */
session.socket.send(session.packet);
/* Return session */
return session;
}
catch (Exception e)
{
Log.e("MYAPP", "exception: " + e.getMessage());
Log.e("MYAPP", "exception: " + e.toString());
}
return null;
}
However, Send() cannot be called directly, since one cannot perform network operations on the UI thread. In order to remedy this, I created an AsyncTask that calls Send(). Now all I have to do is pass the Session object to the AsyncTask and it will send the packet (in theory). The AsyncTask that I created is shown below:
class sendData extends AsyncTask<UDP.Session, Void, UDP.Session>
{
/* Pre-Execute Function */
#Override
protected void onPreExecute ()
{
super.onPreExecute();
}
/* Main AsyncTask Function */
#Override
protected UDP.Session doInBackground(UDP.Session... arguments)
{
/* Send UDP packet */
UDP.Session session = UDP.Send(arguments[0]);
return session;
}
/* Post-Execute Function */
#Override
protected void onPostExecute (UDP.Session session)
{
super.onPostExecute(session);
}
}
The issue that I am experiencing is that I cannot figure out how to return the session object from my AsyncTask. It is critical that I return the session that I passed to the AsyncTask, because otherwise the socket/port becomes corrupted and I get binding exceptions and a whole bunch of other issues when I try to send another packet. I tried using:
UDP.Session nsession = new sendData().execute(ssession).get();
but I get an error that states "Unhandled exceptions: java.lang.InterruptedException, java.util.concurrent.ExecutionException". So my question is what is the best way for me to return the session object that I pass to the AsyncTask so that I can use that same session object next time I want to send a packet.

I was being silly and not paying attention to the compiler warnings about the unhandled exceptions. The AsyncTask call made above (UDP.Session nsession = new sendData().execute(ssession).get();) is indeed correct, but it just needs to be placed inside a try/catch statement catch any possible exceptions. When I changed my code to the following...
try{
session = new sendData().execute(session).get();}
catch (Exception exception){}
...everything worked. I am able to properly return an object from the AsyncTask, and my socket no longer gets corrupted when the AsyncTask finished, allowing me to send as many packets as I want

When to disconnect bosh connection establish from app server to use prebinding in strophe?

This question is Extension of my previous question on this SO question "How to connect XMPP bosh server using java smack library?"
I am using Java as server side language. I have successfully implement xmpp BOSH connection using smach-jbosh thanks to #Deuteu for helping me to achieve this, so far I have modify jbosh's BOSHClient.java file and added two getter method for extracting RID and SID.
Now I have RID and SID on my app server (I am using Apache Tomcat). I need to pass this credential to Strophe (web client) so that it can attach to connection.
Here I have some doubt.
When to disconnect bosh Connection establish from the app server? before passing sid, rid and jid to strophe or after passing sid, rid and jid to strophe?
As per my observation during implementation for the same, I have observed that once bosh connection from the app server has been disconnected, session is expired and SID and RID is no longer useful!!!
I have implemented this logic (Establishing bosh connection and Extracting sid and rid) on a Servlet, here once response has been send from Servlet, Thread will get expired and end BOSH connection will get terminated, so I am not able perform `Attach()` on strophe as session is expired.
Can somebody help me with that problem?

I believe #fpsColton's answer is correct - I'm just added extra info for clarity. As requested on linked thread here is the code changes I made on this - note: I only added the parts where I've labelled "DH"
In BOSHConnection:
// DH: function to preserve current api
public void login(String username, String password, String resource)
throws XMPPException {
login(username, password, resource, false);
}
// DH: Most of this is existing login function, but added prebind parameter
// to allow leaving function after all required pre-bind steps done and before
// presence stanza gets sent (sent from attach in XMPP client)
public void login(String username, String password, String resource, boolean preBind)
throws XMPPException {
if (!isConnected()) {
throw new IllegalStateException("Not connected to server.");
}
if (authenticated) {
throw new IllegalStateException("Already logged in to server.");
}
// Do partial version of nameprep on the username.
username = username.toLowerCase().trim();
String response;
if (config.isSASLAuthenticationEnabled()
&& saslAuthentication.hasNonAnonymousAuthentication()) {
// Authenticate using SASL
if (password != null) {
response = saslAuthentication.authenticate(username, password, resource);
} else {
response = saslAuthentication.authenticate(username, resource, config.getCallbackHandler());
}
} else {
// Authenticate using Non-SASL
response = new NonSASLAuthentication(this).authenticate(username, password, resource);
}
// Indicate that we're now authenticated.
authenticated = true;
anonymous = false;
// DH: Prebind only requires connect and authenticate
if (preBind) {
return;
}
// Set the user.
if (response != null) {
this.user = response;
// Update the serviceName with the one returned by the server
config.setServiceName(StringUtils.parseServer(response));
} else {
this.user = username + "#" + getServiceName();
if (resource != null) {
this.user += "/" + resource;
}
}
// Create the roster if it is not a reconnection.
if (this.roster == null) {
this.roster = new Roster(this);
}
if (config.isRosterLoadedAtLogin()) {
this.roster.reload();
}
// Set presence to online.
if (config.isSendPresence()) {
sendPacket(new Presence(Presence.Type.available));
}
// Stores the autentication for future reconnection
config.setLoginInfo(username, password, resource);
// If debugging is enabled, change the the debug window title to include
// the
// name we are now logged-in as.l
if (config.isDebuggerEnabled() && debugger != null) {
debugger.userHasLogged(user);
}
}
and
// DH
#Override
public void disconnect() {
client.close();
}
then my Client-side (Web Server) wrapper class - for connecting from within JSP is:
Note: This is proving code rather than production - so there's some stuff in here you may not want.
public class SmackBoshConnector {
private String sessionID = null;
private String authID = null;
private Long requestID = 0L;
private String packetID = null;
private boolean connected = false;
public boolean connect(String userName, String password, String host, int port, final String xmppService) {
boolean success = false;
try {
Enumeration<SaslClientFactory> saslFacts = Sasl.getSaslClientFactories();
if (!saslFacts.hasMoreElements()) {
System.out.println("Sasl Provider not pre-loaded");
int added = Security.addProvider(new com.sun.security.sasl.Provider());
if (added == -1) {
System.out.println("Sasl Provider could not be loaded");
System.exit(added);
}
else {
System.out.println("Sasl Provider added");
}
}
BOSHConfiguration config = new BOSHConfiguration(false, host, port, "/http-bind/", xmppService);
BOSHConnection connection = new BOSHConnection(config);
PacketListener sndListener = new PacketListener() {
#Override
public void processPacket(Packet packet) {
SmackBoshConnector.this.packetID = packet.getPacketID();
System.out.println("Send PacketId["+packetID+"] to["+packet.toXML()+"]");
}
};
PacketListener rcvListener = new PacketListener() {
#Override
public void processPacket(Packet packet) {
SmackBoshConnector.this.packetID = packet.getPacketID();
System.out.println("Rcvd PacketId["+packetID+"] to["+packet.toXML()+"]");
}
};
PacketFilter packetFilter = new PacketFilter() {
#Override
public boolean accept(Packet packet) {
return true;
}
};
connection.addPacketSendingListener(sndListener, packetFilter);
connection.addPacketListener(rcvListener, packetFilter);
connection.connect();
// login with pre-bind only
connection.login(userName, password, "", true);
authID = connection.getConnectionID();
BOSHClient client = connection.getClient();
sessionID = client.getSid();
requestID = client.getRid();
System.out.println("Connected ["+authID+"] sid["+sessionID+"] rid["+requestID+"]");
success = true;
connected = true;
try {
Thread.yield();
Thread.sleep(500);
}
catch (InterruptedException e) {
// Ignore
}
finally {
connection.disconnect();
}
} catch (XMPPException ex) {
Logger.getLogger(SmackBoshConnector.class.getName()).log(Level.SEVERE, null, ex);
}
return success;
}
public boolean isConnected() {
return connected;
}
public String getSessionID() {
return sessionID;
}
public String getAuthID() {
return authID;
}
public String getRequestIDAsString() {
return Long.toString(requestID);
}
public String getNextRequestIDAsString() {
return Long.toString(requestID+1);
}
public static void main(String[] args) {
SmackBoshConnector bc = new SmackBoshConnector();
bc.connect("dazed", "i3ji44mj7k2qt14djct0t5o709", "192.168.2.15", 5280, "my.xmppservice.com");
}
}
I confess that I'm don't fully remember why I put the Thread.yield and Thread.sleep(1/2 sec) in here - I think - as you can see with added PacketListener - the lower level functions return after sending data and before getting a response back from the server - and if you disconnect before the server has sent it's response then it (also) causes it to clean up the session and things won't work. However it may be that, as #fpsColton says, this dicsonnect() isn't actually required.
Edit: I now remember a bit more about whay I included sleep() and yield(). I noticed that Smack library includes sleep() in several places, including XMPPConnection.shutdown() as per source. Plus in terms of yield() I had problems in my environment (Java in Oracle Database - probably untypical) when it wasn't included - as per Smack Forum Thread.
Good luck.

After you have created a BOSH session with smack and have extracted the SID+RID values, you need to pass them to Strophe's attach() and from here on out you need to let strophe deal with this connection. Once Strophe has attached, you do not want your server to be doing anything to the connection at all.
If your server side code sends any messages at all to the connection manager after strophe has attached, it's likely that it will send a invalid RID which will cause your session to terminate.
Again, once the session has been established and is usable by strophe, do not attempt to continue using it from the server side. After your server side bosh client completes authentication and you've passed the SID+RID to the page, just destroy the server side connection object, don't attempt to disconnect or anything as this will end your session.
The thing you need to remember is, unlike traditional XMPP connections over TCP, BOSH clients do NOT maintain a persistent connection to the server (this is why we use BOSH in web applications). So there is nothing to disconnect. The persistent connection is actually between the XMPP server and the BOSH connection manager, it's not something you need to deal with. So when you call disconnect from your server side BOSH client, you're telling the connection manager to end the session and close it's connection to the XMPP server, which completely defeats the purpose of creating the session in the first place.

Connecting to SSL WebService

I want to connect to a web service in a SSL connection. I connect to it and I get Service and Port but when I send Requests, it just returns null.
I searched the web but I could not understand what is the problem. may be because it is SSL, I need to connect it different as an Http connection, is it true?
I used auto code generators, they return null too, WireShark says that SSL Packages transmitted correctly but I cannot read the SOAP from these packages because they are SSL.
I test the web service with some applications and the tools and got correct answers from them.
Question:
is it possible that the null value is because SSL connection?
what mistakes could make this null returning?
How can I see the SOAP messeges I send and I get?
Here is My Java Code:
public class WS_TheServeice
{
private static QName qname;
private static URL url;
private static Service service;
private static ImplementationServicePortType sender;
static
{
qname = new QName("http://wservice.com/", "ImplementationService");
try
{
url = new URL("https://to-service?wsdl");
}
catch (MalformedURLException e)
{
e.printStackTrace();
}
service = Service.create(url, qname);
sender = service.getPort(ImplementationServicePortType.class);
}
public static boolean PayToAcceptor(int AcceptorID, int Kipa) throws Exception
{
getUserInfo req = new getUserInfo();
req.zpID = AcceptorID;
req.kipa = Kipa;
getUserInfoResponse user_info = new getUserInfoResponse();//user_info is not NULL here
user_info = sender.getUserInfo(req);//But web server makes it NULL
if (user_info!=null) //// ---- HERE, IT Always return NULL
{
System.out.println("YouWon");
return true;
}
else
{
System.out.println("YouLoose");
return false;
}
}
public static void main(String Args[]) throws Exception
{
PayToAcceptor(12345, 1);
}
}
thanks.

Did you figure out how to do this? I've had similar problems in the past..
Did you try this: SSL Connection for consuming web services ?

Java - Code Coverage

I have a method in one of the classes in my code base that for the life of me, I cannot get into with my junit tests.
Basically this class is called when I request a database connection, if a stale connection is returned, a new connection is established
Here is the snippet of the mthod in my class (trimmed down for this purpose)
public class TCSOracleDataSourceWrapper extends OracleDataSource {
private static final int STALE_CONNECTION_EX_CODE = 17143;
private OracleConnectionCacheManager cacheManager;
private String cacheName;
/** Local log variable **/
private final Log logger = LogFactory.getLog(getClass());
/**
* Class constructor
* #throws SQLException
*/
public TCSOracleDataSourceWrapper() throws SQLException {
super();
}
private static final long serialVersionUID = 1L;
#Override
/**
* Get a connection but if the connection is stale then refresh all DB connections
*
*/
public final Connection getConnection() throws SQLException {
logger.debug("Retrieving a database connection from the pool");
Connection connection = null;
try{
connection = super.getConnection();
}
catch(SQLException e)
{
if(e.getErrorCode() == STALE_CONNECTION_EX_CODE)
{
logger.error("Stale Oracle connection found in the Connection Pool. Refreshing invalid DB connections.");
//refresh invalid connections
cacheManager.refreshCache(cacheName, OracleConnectionCacheManager.REFRESH_INVALID_CONNECTIONS);
//now try to get the connection again
connection = super.getConnection();
}
else
{
throw e;
}
}
return connection;
}}
Any idea how I can ensure my junit tests execute the if statement?
I am currently using EasyMock and Powermock but I cannot find a way to get into this if statment using these tools
All help is greatly appreciated
Thank you
Damien

You should refactor your class to become a proxy for another data source, rather than inherit from one. This way you can easily inject into it a mock data source instead of the real one.
import javax.sql.DataSource;
public class TCSOracleDataSourceWrapper implements DataSource {
...
private DataSource wrappedDataSource;
...
public TCSOracleDataSourceWrapper(DataSource ds) {
wrappedDataSource = ds;
}
...
public final Connection getConnection() throws SQLException {
...
Connection connection = null;
try{
connection = ds.getConnection();
}
catch(SQLException e)
{
...
}
return connection;
}
}

One idea springs to mind: use aggregation rather than inheritance. This problem and others like it would go away because you can then mock the aggregated object to have whatever behavior you want. I don't see another way of getting in there right off hand. In fact, the name TCSOracleDataSourceWrapper already indicates that it's wrapping a data source (aggregation), when it actually isn't.

One quick workaround is to factor out the super.getConnection() call to a new private / protected method. Once you make that change it would be easy to mock the getBaseConnection method using power mock. This is short term fix, like the other answers suggest it is better to use delegation instead of inheritance for the wrapper implementation.
Connection getBaseConnection() throws SQLException {
return super.getConnection();
}
public final Connection getConnection() throws SQLException {
logger.debug("Retrieving a database connection from the pool");
Connection connection = null;
try{
connection = getBaseConnection();
}
catch(SQLException e)
{
if(e.getErrorCode() == STALE_CONNECTION_EX_CODE)
{
logger.error("Stale Oracle connection found in the Connection Pool. Refreshing invalid DB connections.");
//refresh invalid connections
cacheManager.refreshCache(cacheName, OracleConnectionCacheManager.REFRESH_INVALID_CONNECTIONS);
//now try to get the connection again
connection = getBaseConnection();
}
else
{
throw e;
}
}
return connection;
}

JUnit test on URLConnection, use EasyMock?

Hey, have been trying to work this out for last day or so but hitting brick wall. Trying to unit test this bit of code. But not sure if need to use EasyMock or not?? Seem few examples online but seem to be using older techniques.
public boolean verifyConnection(final String url) {
boolean result;
final int timeout = getConnectionTimeout();
if (timeout < 0) {
log.info("No need to verify connection to client. Supplied timeout = {}", timeout);
result = true;
} else {
try {
log.debug("URL: {} Timeout: {} ", url, timeout);
final URL targetUrl = new URL(url);
final HttpURLConnection connection = (HttpURLConnection) targetUrl.openConnection();
connection.setConnectTimeout(timeout);
connection.connect();
result = true;
} catch (ConnectException e) {
log.warn("Could not connect to client supplied url: " + url, e);
result = false;
} catch (MalformedURLException e) {
log.error("Malformed client supplied url: " + url, e);
result = false;
} catch (IOException e) {
log.warn("Could not connect to client supplied url: " + url, e);
result = false;
}
}
return result;
}
It just take's in a url checks its valid and returns T or F.

I have always observed that Mocking Can be avoided as much as possible because it can lead to difficult to maintain JUnit tests and defeat the whole purpose.
My suggestion would be to create a temporary server on your local machine from a JUnit itself.
At the beginning of JUnit you can create a server(not more than 10-15 lines of coding required) using Java sockets and then in your code pass the URL for the local server. This way you are reducing mocking and ensuring maximum code coverage.
Something like this -
public class SimpleServer extends Thread {
public void run() {
try {
serverSocket = new ServerSocket(port);
while (true) {
Socket s = serverSocket.accept();
}
}
catch (IOException e) {
e.printStackTrace();
}
finally {
serverSocket = null;
}
}
}

If you want to mock this method, I'd recommend passing in the URL rather than the String. Don't have your method create the URL it needs; let the client create the URL for you and pass it in. That way your test can substitute a mock if it needs to.
It's almost a dependency injection idea - your method should be given its dependencies and not create them on its own. The call to "new" is the dead giveaway.
It's not a drastic change. You could overload the method and have two signatures: one that accepts a URL string and another that accepts the URL itself. Have the first method create the URL and call the second. That way you can test it and still have the method with the String signature in your API for convenience.

Trying to set up mock implementation of the HttpURLConnection. Like
public class MockHttpURLConnection extends HttpURLConnection {'
then added method to class to override
' protected HttpURLConnection createHttpURLConnection(URL url)
throws IOException {
return (HttpURLConnection) url.openConnection();
}
So test looking something like this:
#Test
public void testGetContentOk() throws Exception
{
String url = "http://localhost";
MockHttpURLConnection mockConnection = new MockHttpURLConnection();
TestableWebClient client = new TestableWebClient();
client.setHttpURLConnection(mockConnection);
boolean result = client.verify(url);
assertEquals(true, result);
}
#Test
public void testDoesNotGetContentOk() throws Exception
{
String url = "http://1.2.3.4";
MockHttpURLConnection mockConnection = new MockHttpURLConnection();
TestableWebClient client = new TestableWebClient();
client.setHttpURLConnection(mockConnection);
boolean result = client.verify(url);
assertEquals(false, result);
}
/**
* An inner, private class that extends WebClient and allows us
* to override the createHttpURLConnection method.
*/
private class TestableWebClient extends WebClient1 {
private HttpURLConnection connection;
/**
* Setter method for the HttpURLConnection.
*
* #param connection
*/
public void setHttpURLConnection(HttpURLConnection connection)
{
this.connection = connection;
}
/**
* A method that we overwrite to create the URL connection.
*/
#Override
public HttpURLConnection createHttpURLConnection(URL url) throws IOException
{
return this.connection;
}
}
First part passed but is getting true for false dummy test, thanks for feedback back so far best site I have found for help. So let me know if think on right track