I found this code witch I tried and it works great but(!). I want to store the file in a folder that I will choose and also get it from a folder that I again will chose. Since the Sender get an argument then I suppose that if I give an argument like /home/user/test.txt then that's ok and it'll work out fine but I don't get how to store the file to a specific folder ( the Server part in other words ). Any ideas?
If I'm wrong about the argument please by all means correct me :D
PS: It works just fine for the Netbeans' default folder ( no specification of folder for the Sender or Server ).
Any help appreciated.
Frankly speaking, though i feel bad about doing your homework, I am just in a good mood :)
In the below code(FileReciever) i have added a new variable folder which is initalized from the first argument passed to main(). So the name of the folder you want to save the file in mus tbe passed as the first argument. The only other line I have changed is:
File file=new File(folder, file_name);
private String folder = "";
public static void main(String[] args) {
try {
folder = args[0];
ServerSocket listener = new ServerSocket(port);
while (true) {
FileReceiver file_rec = new FileReceiver();
file_rec.socket = listener.accept();
new Thread(file_rec).start();
}
}
catch (java.lang.Exception ex) {
ex.printStackTrace(System.out);
}
}
public void run() {
try {
InputStream in = socket.getInputStream();
int nof_files = ByteStream.toInt(in);
for (int cur_file=0;cur_file < nof_files; cur_file++) {
String file_name = ByteStream.toString(in);
File file=new File(folder, file_name);
ByteStream.toFile(in, file);
}
}
catch (java.lang.Exception ex) {
ex.printStackTrace(System.out);
}
}
Related
public void readList () {
try {
FileOutputStream writeData = new FileOutputStream("Accounts.txt");
ObjectOutputStream writeStream = new ObjectOutputStream(writeData);
writeStream.writeObject(AccountCredentials);
writeStream.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
public void writeList() {
try {
FileInputStream readData = new FileInputStream("Accounts.txt");
ObjectInputStream readStream = new ObjectInputStream(readData);
AccountCredentials = (ArrayList <Accounts>) readStream.readObject();
readStream.close();
System.out.println(AccountCredentials.size());
}
catch (Exception e) {
e.printStackTrace();
}
}
My readList method works fine right, I have ¬í sr java.util.ArrayListxÒ™Ça I sizexp w
in the file. My writeList does not. I have a School folder inside the Netbeans folder, and in the main directory is Accounts.txt. Do I need to specify that? My Java file is in Schools/src. It always says my list size is 0
Can you please share the exception or stack trace you are getting and paste it here ? , Also I would highly recommend not to use a flat file for storing the account credentials, rather use any of the identity management solution and db driven account management. Did you also try to debug the following line "ObjectInputStream readStream = new ObjectInputStream(readData);"
public class deleteFile {
public static void main(String args[]){
StringBuffer fileNameStr = new StringBuffer();
fileNameStr.append("c:/");
fileNameStr.append("Test");
File file = new File(fileNameStr.toString());
String systemDateTime = null;
try {
systemDateTime = con.getSystemDateTime();
} catch (SQLException e) {
file.delete();
}
}
}
According to this code, when I get SQLException, it can't delete file. Why?
There is nothing special about deleting a file in a catch block.
If your code (above) is not deleting the file, then it could be a number of things:
You may have the file pathname incorrect.
The file may not exist in the first place.
Your application may not have permission to delete the file, due to normal file / directory permission issues, "mandatory access control" restrictions (e.g. SELinux) or Java sandbox restrictions.
The file may be undeletable because it is "in use" ... on Windows.
That particular exception may not be being thrown.
Your catch block with SqlException never catching.
Use finally{} block in order to delete file or free resource.
Actually my full source code is,
public class deleteFile {
public static void main(String args[]){
-------------------------
StringBuffer fileNameStr = new StringBuffer();
fileNameStr.append(.....);
fileNameStr.append(.....);
File file = new File(fileNameStr.toString());
PrintWriter printWriter = new PrintWriter(new BufferedWriter(
new OutputStreamWriter(new FileOutputStream(file),
"windows-31j")));
String systemDateTime = null;
try {
systemDateTime = con.getSystemDateTime();
} catch (SQLException e) {
file.delete();
}
}
Finally I found the solution that is need to close printWriter before deletion file. Thank you for your advice.
try {
systemDateTime = con.getSystemDateTime();
} catch (SQLException e) {
printWriter.flush();
printWriter.close();
file.delete();}
}
I'm trying to copy files from the assets folder to the device folder using this function:
public static void copyJSON(Context aContext) {
AssetManager assetManager = aContext.getResources().getAssets();
String[] pFiles = null;
try {
pFiles = assetManager.list("ConfigurationFiles");
} catch (IOException e) {
Log.e("tag", "Failed to get asset file list.", e);
}
if (pFiles != null) for (String pJsonFileName : pFiles) {
InputStream tIn = null;
OutputStream tOut = null;
try {
tIn = assetManager.open("ConfigurationFiles" + File.separator + pJsonFileName);
String[] pList = aContext.getFilesDir().list(); //just for test
File pOutFile = new File(aContext.getFilesDir(), pJsonFileName);
tOut = new FileOutputStream(pOutFile);
if (pOutFile.exists()) {
copyFile(tIn, tOut);
}
} catch (IOException e) {
Log.e("tag", "Failed to copy asset file: " + pJsonFileName, e);
} finally {
if (tIn != null) {
try {
tIn.close();
} catch (IOException e) {
Log.e("tag", "Fail closing", e);
}
}
if (tOut != null) {
try {
tOut.close();
} catch (IOException e) {
Log.e("tag", "Fail closing", e);
}
}
}
}
}
If I delete the App and run the code, the variable pList is empty as I expect but the pOutFile.exists()returns true ALWAYS!!.
I don't want to copy them again every time I open my App, and I'm doing this because all my app uses JSON to navigate thru all the screens, so If I change any value in my BBDD a WS send a new JSON file and the App respond in accordance for example a button is no longer needed, so the first time you download my App I copy the original JSON and then if you use the app an if you have internet connection you will download a new JSON file that it is more accurate than the one that is in the Bundle and it will be override, this is because as far as I know I can't change the files that are in the assets folder.
I have read everywhere and all say the same use this:
File pOutFile = new File(aContext.getFilesDir(), pJsonFileName);
And then ask for this:
pOutFile.exists()
I don't know what I'm doing wrong.
Thanks for all your help.
put it this way:
File pOutFile = new File(aContext.getFilesDir(), pJsonFileName);
if (pOutFile.exists()) {
tOut = new FileOutputStream(pOutFile);
copyFile(tIn, tOut);
}
and everything should work fine. Remember the FileOutputStream creates the file it should stream to if possible and non existing
The problem is you're essentially creating a file and then checking if it exists.
try {
tIn = assetManager.open("ConfigurationFiles" + File.separator + pJsonFileName);
String[] pList = aContext.getFilesDir().list(); //just for test
File pOutFile = new File(aContext.getFilesDir(), pJsonFileName);
// See here: you're creating a file right here
tOut = new FileOutputStream(pOutFile);
// And that file will be created in the exact location of the file
// you're trying to check:
if (pOutFile.exists()) { // Will always be true if FileOutputStream was successful
copyFile(tIn, tOut);
}
}
You should instead create your FileOutputStream AFTER you've done your existence check.
Source: http://docs.oracle.com/javase/7/docs/api/java/io/FileOutputStream.html
A file that you have just created without getting an exception always exists. The test is pointless. Remove it.
I've been trying to do this on my own for the past couple hours and am kinda losing it a little.
All I want to do is open a file, read it and display it to the console; that's it.
I'm using eclipse to develop for android 2.3.3.
I have tried using a bunch of different ways with code that I have found here, and on other sites. Here is what I have now and how its all called:
In the OnCreate function:
setContentView(new TestMap(this));
The testMap class:
TestMap(Context context){
super(context);
// might need to be on the panel class
loadTileFile("worldonelayout.txt", context);
in the same class:
private void loadTileFile (String filename, Context context){
FileInputStream input = null;
InputStreamReader reader = null;
char[] inputBuffer = new char[256];
String data = null;
try {
input = context.openFileInput("worldonelayout.txt");
reader = new InputStreamReader(input);
reader.read(inputBuffer);
data = new String(inputBuffer);
System.out.println(data);
Toast.makeText(context, "Text read", Toast.LENGTH_SHORT).show();
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(context, "Text not read", Toast.LENGTH_SHORT).show();
} finally {
try {
input.close();
reader.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
This code doesnt work. It always hits the exception.
"/data/data/com.name.somethingiremoved/files/worldonelayout.txt (No such file or directory)".
This happens at the first CATCH. BTW my file is in the root directory: Documents\Eclipse\workspace\project\worldonelayout.txt. I can also see the file in the browser on the left
From what I have seen here and on other sites, it is something to do with the Context class being derived from the Activity? I don't want to have this code in the same class as my activity. Is there a way round this?
If you need anything more from me, let me know.
The open file is looking for a file on the phone's file system, not on the computer's. Its telling you exactly where it expects to find it - on the phone under /data/data/com.name.somethingiremoved/files/worldonelayout.txt
I've hosted a text file which I would like to load into a string using java.
My code doesn't seem to work producing errors, any help?
try {
dictionaryUrl = new URL("http://pluginstudios.co.uk/resources/studios/games/hangman/dictionary.dic");
} catch (MalformedURLException catchMalformedURLException) {
System.err.println("Error 3: Malformed URL exception.\n"
+ " Dictionary failed to load.");
}
// 'Dictionary' scanner setting to file
// 'src/Main/Dictionary.dic'
DictionaryS = new Scanner(new File(dictionaryUrl));
System.out.println("Default dictionary loaded.");
UPDATE 1: The file doesn't seem to load going to the catch. But the file exists.
You could do something that this tutorial does
public class WebPageScanner {
public static void main(String[] args) {
try {
URLConnection connection =
new URL("http://java.net").openConnection();
String text = new Scanner(
connection.getInputStream()).
useDelimiter("\\Z").next();
} catch (IOException e) {
e.printStackTrace();
}
}
}
You need to use HttpClient and retrieve the data as a string or string buffer.
then use parse or read as file.
Something like this should work in your case:
DictionaryS = new Scanner(dictionaryUrl.openStream());
JavaDoc tells us:
File(URI uri)
Creates a new File instance by converting the given file: URI into an abstract pathname.
We can't create and use a File instance for any other resource type (like http).