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FTPClient connection with Java on AWS Virtual Machine

I'm trying to connect to my FTP server in Java SE 1.8. To do so I use this method :
private void connectFTP() {
String server = "ftp.XXXXXXXXXX.site";
int port = 21;
String user = "XXXX";
String pass = "XXXX";
if(!ftpConnexionSuccess.get())
{
client = new FTPClient();
client.configure(new FTPClientConfig(FTPClientConfig.SYST_UNIX));
try {
client.connect(server, port);
ftpConnexionSuccess.set(client.login(user, pass));
if (!ftpConnexionSuccess.get()) {
System.out.println("Could not login to the server");
return;
}
else
{
System.out.println("LOGGED IN SERVER");
client.changeWorkingDirectory("/crypto");
listenedFile = getListenedFile();
System.out.println(listenedFile.getName());
if(listenedFile != null)
{
baseFileTimeStamp.set(listenedFile.getTimestamp().getTimeInMillis());
}
System.out.println(baseFileTimeStamp);
}
} catch (Exception ex) {
System.err.println("FTP connection error : Sleeping for 5 seconds before trying again (" + ex.getMessage() + ")");
ex.printStackTrace();
try {
Thread.sleep(5000);
} catch (InterruptedException e) {e.printStackTrace();}
try {
client.disconnect();
} catch (IOException e) {e.printStackTrace();}
connectFTP();
}
}
}
It works great when I'm on Eclipse and when I export the app on my Windows 10.
Nonetheless, when I try to launch the app on my AWS Webmachine I get a null pointer exception at "listenedFile". The method to listen to this file is the one below.
private FTPFile getListenedFile() {
FTPFile returnedFile = null;
try {
for(FTPFile file : client.listFiles())
{
if(file.getName().contains("filetolisten.txt"))
returnedFile = file;
}
} catch (Exception e) {
System.out.println(e.getMessage());
e.printStackTrace();
try {
client.disconnect();
} catch (IOException e1) {e1.printStackTrace();}
connectFTP();
return getListenedFile();
}
return returnedFile;
}
I thought it was because of the line
client.configure(new FTPClientConfig(FTPClientConfig.SYST_UNIX));
I tried to delete the line, and to replace SYST_UNIX with SYST_NT, but nothing worked.
I tried to delete the line, and to replace SYST_UNIX with SYST_NT, but nothing worked. Also updated Java, updated the common-nets library. Nothing worked

How to follow IntelliJ-IDEA's advice "catch branch identical" on try/catch block?

I'm using "ObjectInputStream" to load serialized 2D String arrays.
The problem is, My IDE, Intellij-IDEA, will throw an error unless I put a special catch condition for a ClassNotFoundException. However, when I do that it advises, "'catch' branch identical to 'IOException' branch".
I don't know what this is implying I should do.
How can I load serialized objects without getting either advice or an error?
My code:
private String[][] getPossArray(String race, boolean isFirstName) {
String[][] retVal = new String[0][];
try {
FileInputStream fis = new FileInputStream("./res/binary_files/Human_FirstNameString[][].ser");
ObjectInputStream ois = new ObjectInputStream(fis);
retVal = (String[][]) ois.readObject();
ois.close();
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
return retVal;
}

Thanks to guleryuz's comment, I found out that the advice from IntelliJ was trying to tell me that I could get rid of the advice notification by changing my catch block to catch (IOException | ClassNotFoundException e) instead of having each catch statement on it's own line.
Old Catch-Block Version:
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
New Catch-Block Version:
} catch (IOException | ClassNotFoundException e) {
e.printStackTrace();
}

Get data from getter method instead of passing in a Bundle

I need to pass some Bitmaps from one activity to another, and, since the size limit of the Bundle won't let me pass these images (even using a byte array*), I thought that I could use a getter method between these Activities.
-But, since I'm still not a master in Android (Java), I don't know if that would make any difference, and, if it does, what should I watch out for when using it.
the byte array did reduce the total size(at about 60%), but it still wasn't enough
scaling down is a way out, but just in case any other solution works

save your object in a file
private void saveDataToFile() {
FileOutputStream fileOutputStream = null;
try {
fileOutputStream = getContext().openFileOutput("fileName", Context.MODE_PRIVATE);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (NullPointerException e) {
}
ObjectOutputStream objectOutputStream = null;
try {
objectOutputStream = new ObjectOutputStream(fileOutputStream);
} catch (IOException e) {
e.printStackTrace();
} catch (NullPointerException e) {
}
try {
if (objectOutputStream != null) {
objectOutputStream.writeObject(yourObject); //which data u want to save
}
} catch (IOException e) {
e.printStackTrace();
}
try {
if (objectOutputStream != null) {
objectOutputStream.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
Retrieve the object from another activity
private void getDataFromFile() {
FileInputStream fileInputStream = null;
try {
fileInputStream = getContext().openFileInput("fileName");
} catch (FileNotFoundException e) {
e.printStackTrace();
return;
}
ObjectInputStream objectInputStream = null;
try {
objectInputStream = new ObjectInputStream(fileInputStream);
} catch (IOException |NullPointerException e) {
e.printStackTrace();
}
try {
yourObject = (ObjectClass) objectInputStream.readObject();
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
try {
objectInputStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}

Pass through Uri by writing getter method in POJO class

If you want to use getter setter, just create URI of your bitmap and pass to setter method in POJO class and then retrieve using getter method of POJO class.

Printing to multiple output files in java

I have two arrays that I want to print to separate files. Here's my code:
try {
PrintStream out = new PrintStream(new FileOutputStream(
"Edges.txt"));
for (i = 0; i < bcount; i++) {
out.println(b[i][0] + " " + b[i][1]);
}
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
} catch (Exception ex) {
ex.printStackTrace();
}
try {
PrintStream out = new PrintStream(new FileOutputStream(
"Nodes.txt"));
for (i = 0; i < bigbIter; i++) {
out.println(bigb[i]);
}
out.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
} catch (Exception ex) {
ex.printStackTrace();
}
If I only use the first set of try / catch / catch, it works perfectly. But when I use both it doesn't work, giving me the errors "illegal start of type ... } catch" and "error: class, interface, or enum expected". What am I doing wrong?

} catch (FileNotFoundException e) {
e.printStackTrace();
}
} catch (Exception ex) {
ex.printStackTrace();
}
You have an extra }, which throws off the parser and gives you lots of errors.

You should write a method to write to the file. Just pass the file name and data. You should see that you have too many closing brackets, get your IDE to highlight brackets.
Lesson is just don't copy/paste and then edit the catch block when you want it again!
Edit: Also in java 7 you can have multiple catches in one block, it is better to do this:
catch (FileNotFoundException | IOException e)
{
}

Using sockets and Object IO streams in Android programming

I'm trying to implement multiplayer in a game I've been writing, and I've gotten everything to successfully connect (I think..), but when I'm running it, there's an EOFException thrown by the client, and the object (an ArrayList) isn't successfully received.
Code for the server thread:
class ServerThread implements Runnable
{
ServerSocket server = null;
Socket controlSocket = null;
ObjectOutputStream outStream = null;
ObjectInputStream inStream = null;
#Override
public void run() {
setupConnection();
while(true){
sendObject(out.getStuff());
}
}
void setupConnection(){
Log.e("OUTPUTSHOOTER","init-connect");
try {
server = new ServerSocket(SERVERPORT);
Log.e("OUTPUTSHOOTER","server initiated port: "+SERVERPORT);
controlSocket = server.accept();
Log.e("OUTPUTSHOOTER","connected");
inStream = new ObjectInputStream(controlSocket.getInputStream());
outStream = new ObjectOutputStream(controlSocket.getOutputStream());
} catch (StreamCorruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Log.e("OUTPUTSHOOTER",server+" "+controlSocket+" "+inStream+" "+outStream);
}
public Object recieveObject(){
Object o = null;
try {
o = inStream.readObject();
} catch (OptionalDataException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return o;
}
public void sendObject(Object o)
{
try {
outStream.writeObject(o);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
And then the code for the client:
class ClientThread implements Runnable
{
Socket controlSocket = null;
ObjectOutputStream outStream = null;
ObjectInputStream inStream = null;
#Override
public void run() {
setupConnection();
while(true){
Log.e("OUTPUTSHOOTER","recieving");
Object in = recieveObject();
if(in!= null && in instanceof ArrayList)
{
Log.e("OUTPUTSHOOTER","loading");
out.load((ArrayList<UniverseObject>)in);
}
}
}
void setupConnection(){
Log.e("OUTPUTSHOOTER","ip: "+SERVERIP);
while(controlSocket == null) {
try {
controlSocket = new Socket(SERVERIP,SERVERPORT);
Log.e("OUTPUTSHOOTER","socket connected");
} catch (IOException e) {
e.printStackTrace();
}
}
try {
Log.e("OUTPUTSHOOTER","attempting streams");
outStream = new ObjectOutputStream(controlSocket.getOutputStream());
Log.e("OUTPUTSHOOTER","output working");
inStream = new ObjectInputStream(controlSocket.getInputStream());
Log.e("OUTPUTSHOOTER","streams connected");
} catch (StreamCorruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public Object recieveObject(){
Object o = null;
try {
o = inStream.readObject();
} catch (OptionalDataException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return o;
}
public void sendObject(Object o)
{
try {
outStream.writeObject(o);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
What does this mean? And perhaps more importantly, how can I fix it? Thanks in advance..

I don't see you closing your outputstream.
See this SO topic: Problem serializing and deserializing ArrayList

Turns out the server wasn't properly initiating it's input and output streams, even though its sockets were successful. Dunno why, but it only works if I started with the output stream first, then the input (?). Having some other really strange bugs, but at least the communication seems to work.. I'll look more in to them before posting here about it. Thanks guys!