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Java FileWriter class - java.io.FileNotFoundException: * no such file or directory -Ubuntu

I am using this method to generate some turtle files .ttl in a sub-directory of my project:
public static void write(int id, int depth){
try {
FileWriter fw = null;
switch (getName()){
case ("KG1"):
fw = new FileWriter("WWW/KG1/" + depth + "/" + id + ".ttl");
break;
case ("KG2"):
fw = new FileWriter("WWW/KG2/" + depth + "/" + id + ".ttl");
}
// Write something
fw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
But I am having this exception when I have put my project in Ubuntu (it is still working fine in Windows) in the java class FileWriter:
java.io.FileNotFoundException: /WWW/KG1/2/0.ttl (No such file or directory)
I am using Eclipse Neon for both OSs, but it seems that Ubuntu is not happy about it.
Here is what I have tried so far:
Adding write permissons to ALL files and directories under the main project directory
Using absolute path instead of relative path, by using System.getProperty("usr.dir"), and plotting all the path string I am giving to FileWriter, but it does not work.
Any advice?
Thanks!

You can make things easier for yourself by using Path and File objects. Here is a version that optionally creates the wanted directory if it doesn't exist
Path path = Paths.get("WWW", "KG1", String.valueOf(depth));
try {
Files.createDirectories(path);
FileWriter fw = new FileWriter(new File(path.toFile(), id + ".ttl"));
fw.close();
} catch (IOException e) {
e.printStackTrace();
}
Note that I intentionally skipped the switch to simplify the answer

I would try using File.separator and make sure the parent directory exists.
Here is an example (may have syntax issues).
final String WWW = "WWW";
final String KG1 = "KG1";
final String KG2 = "KG2";
final String extension = ".ttl";
int id = 1;
int depth = 1;
String filePath = "." // current dir
+ File.separator
+ WWW
+ File.separator
+ KG1
+ File.separator
+ depth
+ File.separator
+ id
+ extension;
File file = new File(filePath);
// make sure parent dir exists (else created)
file.getParentFile().mkdirs();
FileWriter writer = new FileWriter(file);

Create directory in Java but don't throw error if it already exists [duplicate]

The condition is if the directory exists it has to create files in that specific directory without creating a new directory.
The below code only creates a file with the new directory but not for the existing directory . For example the directory name would be like "GETDIRECTION":
String PATH = "/remote/dir/server/";
String fileName = PATH.append(id).concat(getTimeStamp()).append(".txt");
String directoryName = PATH.append(this.getClassName());
File file = new File(String.valueOf(fileName));
File directory = new File(String.valueOf(directoryName));
if (!directory.exists()) {
directory.mkdir();
if (!file.exists() && !checkEnoughDiskSpace()) {
file.getParentFile().mkdir();
file.createNewFile();
}
}
FileWriter fw = new FileWriter(file.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
bw.write(value);
bw.close();

Java 8+ version:
Files.createDirectories(Paths.get("/Your/Path/Here"));
The Files.createDirectories() creates a new directory and parent directories that do not exist. This method does not throw an exception if the directory already exists.

This code checks for the existence of the directory first and creates it if not, and creates the file afterwards. Please note that I couldn't verify some of your method calls as I don't have your complete code, so I'm assuming the calls to things like getTimeStamp() and getClassName() will work. You should also do something with the possible IOException that can be thrown when using any of the java.io.* classes - either your function that writes the files should throw this exception (and it be handled elsewhere), or you should do it in the method directly. Also, I assumed that id is of type String - I don't know as your code doesn't explicitly define it. If it is something else like an int, you should probably cast it to a String before using it in the fileName as I have done here.
Also, I replaced your append calls with concat or + as I saw appropriate.
public void writeFile(String value){
String PATH = "/remote/dir/server/";
String directoryName = PATH.concat(this.getClassName());
String fileName = id + getTimeStamp() + ".txt";
File directory = new File(directoryName);
if (! directory.exists()){
directory.mkdir();
// If you require it to make the entire directory path including parents,
// use directory.mkdirs(); here instead.
}
File file = new File(directoryName + "/" + fileName);
try{
FileWriter fw = new FileWriter(file.getAbsoluteFile());
BufferedWriter bw = new BufferedWriter(fw);
bw.write(value);
bw.close();
}
catch (IOException e){
e.printStackTrace();
System.exit(-1);
}
}
You should probably not use bare path names like this if you want to run the code on Microsoft Windows - I'm not sure what it will do with the / in the filenames. For full portability, you should probably use something like File.separator to construct your paths.
Edit: According to a comment by JosefScript below, it's not necessary to test for directory existence. The directory.mkdir() call will return true if it created a directory, and false if it didn't, including the case when the directory already existed.

Trying to make this as short and simple as possible. Creates directory if it doesn't exist, and then returns the desired file:
/** Creates parent directories if necessary. Then returns file */
private static File fileWithDirectoryAssurance(String directory, String filename) {
File dir = new File(directory);
if (!dir.exists()) dir.mkdirs();
return new File(directory + "/" + filename);
}

I would suggest the following for Java8+.
/**
* Creates a File if the file does not exist, or returns a
* reference to the File if it already exists.
*/
public File createOrRetrieve(final String target) throws IOException {
final File answer;
Path path = Paths.get(target);
Path parent = path.getParent();
if(parent != null && Files.notExists(parent)) {
Files.createDirectories(path);
}
if(Files.notExists(path)) {
LOG.info("Target file \"" + target + "\" will be created.");
answer = Files.createFile(path).toFile();
} else {
LOG.info("Target file \"" + target + "\" will be retrieved.");
answer = path.toFile();
}
return answer;
}
Edit: Updated to fix bug as indicated by #Cataclysm and #Marcono1234. Thx guys:)

code:
// Create Directory if not exist then Copy a file.
public static void copyFile_Directory(String origin, String destDir, String destination) throws IOException {
Path FROM = Paths.get(origin);
Path TO = Paths.get(destination);
File directory = new File(String.valueOf(destDir));
if (!directory.exists()) {
directory.mkdir();
}
//overwrite the destination file if it exists, and copy
// the file attributes, including the rwx permissions
CopyOption[] options = new CopyOption[]{
StandardCopyOption.REPLACE_EXISTING,
StandardCopyOption.COPY_ATTRIBUTES
};
Files.copy(FROM, TO, options);
}

Simple Solution using using java.nio.Path
public static Path createFileWithDir(String directory, String filename) {
File dir = new File(directory);
if (!dir.exists()) dir.mkdirs();
return Paths.get(directory + File.separatorChar + filename);
}

If you create a web based application, the better solution is to check the directory exists or not then create the file if not exist. If exists, recreate again.
private File createFile(String path, String fileName) throws IOException {
ClassLoader classLoader = getClass().getClassLoader();
File file = new File(classLoader.getResource(".").getFile() + path + fileName);
// Lets create the directory
try {
file.getParentFile().mkdir();
} catch (Exception err){
System.out.println("ERROR (Directory Create)" + err.getMessage());
}
// Lets create the file if we have credential
try {
file.createNewFile();
} catch (Exception err){
System.out.println("ERROR (File Create)" + err.getMessage());
}
return file;
}

A simple solution using Java 8
public void init(String multipartLocation) throws IOException {
File storageDirectory = new File(multipartLocation);
if (!storageDirectory.exists()) {
if (!storageDirectory.mkdir()) {
throw new IOException("Error creating directory.");
}
}
}

If you're using Java 8 or above, then Files.createDirectories() method works the best.

Can't delete file in java on windows ....?

I am trying to use file.delete() but it does not delete file ? I tested it on linux it delete files but on windows it does not delete file why..?
code :
private File getFiletobeUpload(File foto) {
boolean errorRename = true;
File uploadFile = null;
File testFile = foto;
String subdirname = this.checkDir(foto);
if (testFile.canWrite()) {
uploadFile = new File(AppConstants.PHOTOPATH + "/" + subdirname + "/" + testFile.getName());
try {
FileInputStream origStream = new FileInputStream(testFile);
FileOutputStream outStream = new FileOutputStream(uploadFile);
origStream.getChannel().transferTo(0, testFile.length(), outStream.getChannel());
origStream.close();
origStream = null;
outStream.close();
outStream = null;
} catch (Exception e) {
this.errorString += "error while writing to orig dir";
logger.error(e);
}
errorRename = !testFile.delete();
if (errorRename) {
this.errorString += "error while deleting the file";
}
}
testFile = null;
return uploadFile;
}

your code seems a bit odd, you are checking "testFile" for write access but then actually reading from it (FileInputStream). Is the first try/catch block running without exception? Maybe you should check if the file even exists:
System.out.println("File exists: "+testFile.exists());
errorRename = !testFile.delete();
Also if you just want to rename a file, use:
file.renameTo(File dest)

A general suggestion: consider using the classes in the java.nio package to your file IO if you can (not sure which version of Java you're running with) because the error handling is improved and you should be able to find a more specific reason for the failure based on the type of exception thrown and the exception message.

As per API, the disk-drive specifier - "/" for the UNIX root directory, and "\\" for a Microsoft Windows UNC pathname.
so for windows:
uploadFile = new File(AppConstants.PHOTOPATH + "\\" + subdirname + "\\" + testFile.getName());

Java don't read in pictures and audio files with relative path

In java i programmed a small program to play audio file and sow pictures:
At first i make a final String with the path and then i made a file object.
At least i save the returned array in my "tracks" variable.
This is my code:
private static final String PATH = "../src/audio/";
private static final File FILE = new File(PATH);
tracks = liesAudioDateien(file);
private AudioClip[] liesAudioDateien (File inputFile) {
File[] dateFileArray;
AudioClip[] tracks;
dateFileArray = inputFile.listFiles();
tracks = new AudioClip[dateFileArray.length];
for (int i = 0; i < tracks.length; i++) {
if (dateFileArray[i].isFile()) {
try {
tracks[i] = Applet.newAudioClip(dateFileArray[i].toURL());
} catch (IOException ex) {
System.err.println("Oops!: -- " + ex.toString());
}
}
}
return tracks;
If I run this code, I get an error:
Exception in thread "main" java.lang.NullPointerException
at source.Sound.liesAudioDateien(Sound.java:32)
Sound.java:32:
This is tracks = new AudioClip[dateFileArray.length]; line.
If i try with an absolute path, it does work!
What i do wrong?

Change "../src/audio/" to "./src/audio/"

Your path is relative, which is resolved to be relative to the current working directory. The current working directory is not what you think it is.
Try to do this before inputFile.listFiles();
System.out.println(inputFile.getAbsolutePath());
And see what Java thinks the absolute path should be.

File.listFiles returns null if the abstract pathname does not denote a directory.
You need to make sure inputFile does denote a directory to ensure dateFileArray is not null.

Try it with File.separator in place of forward/backward slash.
ex:
String soundDir = "." + File.separator + "folderName" + File.separator;
String fileName = "sound.wav";
String filePath = soundDir+ + fileName;

Add .txt extension in JFileChooser

I have a method that get text from a JTextArea, create a file and write text on it as code below:
public void createTxt() {
TxtFilter txt = new TxtFilter();
JFileChooser fSave = new JFileChooser();
fSave.setFileFilter(txt);
int result = fSave.showSaveDialog(this);
if(result == JFileChooser.APPROVE_OPTION) {
File sFile = fSave.getSelectedFile();
FileFilter selectedFilter = fSave.getFileFilter();
String file_name = sFile.getName();
String file_path = sFile.getParent();
try{
if(!sFile.exists()) {
sFile.createNewFile();
BufferedWriter out = new BufferedWriter(new FileWriter(sFile));
out.write(jTextArea1.getText());
out.close();
JOptionPane.showMessageDialog(null, "Warning file • " + file_name + " • created succesfully in \n" + file_path);
} else {
String message = "File • " + file_name + " • already exist in \n" + file_path + ":\n" + "Do you want to overwrite?";
String title = "Warning";
int reply = JOptionPane.showConfirmDialog(null, message, title, JOptionPane.YES_NO_OPTION);
if(reply == JOptionPane.YES_OPTION){
sFile.delete();
sFile.createNewFile();
BufferedWriter out = new BufferedWriter(new FileWriter(sFile));
out.write(jTextArea1.getText());
out.close();
JOptionPane.showMessageDialog(null, "File • " + file_name + " • overwritten succesfully in \n" + file_path);
}
}
}
catch(IOException e) {
System.out.println("Error");
}
}
}
and a txt file filter
public class TxtFilter extends FileFilter{
#Override
public boolean accept(File f){
return f.getName().toLowerCase().endsWith(".txt")||f.isDirectory();
}
#Override
public String getDescription(){
return "Text files (*.txt)";
}
}
The file filter for txt works fine but what I want is to add ".txt" extension when I type file name.
How to I have to modify my code?

I just use this
File fileToBeSaved = fileChooser.getSelectedFile();
if(!fileChooser.getSelectedFile().getAbsolutePath().endsWith(suffix)){
fileToBeSaved = new File(fileChooser.getSelectedFile() + suffix);
}

UPDATE
You pointed me out that the check for existing files doesn't work. I'm sorry, I didn't think of it when I suggested you to replace the BufferedWriter line.
Now, replace this:
File sFile = fSave.getSelectedFile();
with:
File sFile = new File(fSave.getSelectedFile()+".txt");
With this replacement, it isn't now needed to replace the line of BufferedWriter, adding .txt for the extension. Then, replace that line with the line in the code you posted (with BufferedWriter out = new BufferedWriter(new FileWriter(sFile)); instead of BufferedWriter out = new BufferedWriter(new FileWriter(sFile+".txt"));).
Now the program should work as expected.
I forgot to mention that you have to comment the line:
sFile.createNewFile();
In this way, you're creating an empty file, with the class File.
Just after this line, there is: BufferedWriter out = new BufferedWriter(new FileWriter(sFile));.
With this line, you are creating again the same file. The writing procedure is happening two times! I think it's useless to insert two instructions that are doing the same task.
Also, on the BufferedWriter constructor, you can append a string for the file name (it isn't possible on File constructor), that's the reason why I added +".txt" (the extension) to sFile.

This is a utility function from one of my programs that you can use instead of JFileChooser.getSelectedFile, to get the extension too.
/**
* Returns the selected file from a JFileChooser, including the extension from
* the file filter.
*/
public static File getSelectedFileWithExtension(JFileChooser c) {
File file = c.getSelectedFile();
if (c.getFileFilter() instanceof FileNameExtensionFilter) {
String[] exts = ((FileNameExtensionFilter)c.getFileFilter()).getExtensions();
String nameLower = file.getName().toLowerCase();
for (String ext : exts) { // check if it already has a valid extension
if (nameLower.endsWith('.' + ext.toLowerCase())) {
return file; // if yes, return as-is
}
}
// if not, append the first extension from the selected filter
file = new File(file.toString() + '.' + exts[0]);
}
return file;
}

I've done this function for this purpose :
/**
* Add extension to a file that doesn't have yet an extension
* this method is useful to automatically add an extension in the savefileDialog control
* #param file file to check
* #param ext extension to add
* #return file with extension (e.g. 'test.doc')
*/
private String addFileExtIfNecessary(String file,String ext) {
if(file.lastIndexOf('.') == -1)
file += ext;
return file;
}
Then you can use the function for example in this way :
JFileChooser fS = new JFileChooser();
String fileExt = ".txt";
addFileExtIfNecessary(fS.getSelectedFile().getName(),fileExt)