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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.

How do I make a new file everytime so nothing gets overwritten?

I have this code here that saves bitmaps of images as a GIF file called test, but everytime the user saves it as test.gif so its constantly overwriting.
What are some ways to avoid overweriting and generate a new filename everytime programmatically?
if(imagesPathList !=null){
if(imagesPathList.size()>1) {
Toast.makeText(MainActivity.this, imagesPathList.size() + " no of images are selected", Toast.LENGTH_SHORT).show();
File sdCard = Environment.getExternalStorageDirectory();
File dir = new File (sdCard.getAbsolutePath() + "/dir1/dir2");
dir.mkdirs();
File file = new File(dir, "test.gif");
try{
FileOutputStream f = new FileOutputStream(file);
f.write(generateGIF(list));
} catch(Exception e) {
e.printStackTrace();
}

A quick and dirty solution is to put the system time in the filename:
File file = new File(dir, "test_" + System.currentTimeMillis() +".gif");
As long as that method isn't executed at the exact same millisecond, you won't have duplicates.

You can use java.io.File.createTempFile("test", ".gif", dir)
This creates unique filename but they might get significantly long after some time.
Alternatively you can create a method that creates unique filesnames yourself:
private File createNewDestFile(File path, String prefix, String suffix) {
File ret = new File(path, prefix + suffix);
int counter = 0;
while (ret.exists()) {
counter++;
ret = new File(path, prefix + "_" + counter + suffix);
}
return ret;
}
Instead of
File file = new File(dir, "test.gif");
you call
File file = createNewDestFile(dir, "test", ".gif");
This is not thread safe. For that you need a more sophisticated method (e.g. synchronize it and create a FileOutputStream instead of a File which is creating the file already before another call checks of the method checks its existence).

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());

Transferring a File in android

I have been struggling for two days to try and understand the process of copying a file to the SD card in Android. None of the methods I tried thus far seem to work.
My application has a Profile Picture setting. I need to launch an Intent to pick an Image, then I need to copy the Image to a new Path on the SD Card and then return the Uri of the new Image at which point I check the Images Orientation (Samsung Pics seem to be rotated 90 degrees sometimes). I then rotate the Image correctly and then save the Uri to a SharedPreferences File for use in the Application.
This is my Intent Call:
case R.id.ib_userImage:
i = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.INTERNAL_CONTENT_URI);
startActivityForResult(i, 1);
break;
This is my current horrific attempt at the copy function, I have changed it so much I am not very lost.
public static void copyImage(Context context, Uri uri) {
Log.i("ATTENTION", "Inside the Copy Function");
Log.i("ATTENTION", "Trying to copy file: " + uri.toString());
try {
String outputPath = Environment.getExternalStorageDirectory() + "/appname/images/";
File dir = new File(outputPath);
if(!dir.exists()) {
dir.mkdirs();
}
Log.i("ATTENTION", "Destination File Created at: " + dir.toURI().toString());
InputStream in = context.getContentResolver().openInputStream(uri);
OutputStream out = new FileOutputStream(dir);
byte[] buffer = new byte[1024];
while(in.read(buffer) > 0) {
out.write(buffer);
}
out.flush();
out.close();
in.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Log.i("ATTENTION", "File Copied");
}
Thank you for the help, I will provide any other information you might need.
Update:
I am now getting the Following Exception During the Write Process
java.io.FileNotFoundException: /storage/emulated/0/appname/images: open failed: EISDIR (Is a Directory);
My Understaing is that I specified a Directory with the following code:
String outputPath = Environment.getExternalStorageDirectory() + "/medinfo/images/";
File dir = new File(outputPath);
if(!dir.exists()) {
dir.mkdirs();
}
and then passed it to the OutputStream:
OutputStream out = new FileOutputStream(dir);
and the OutputStream would create the file for me within that Directory.
I didn't think that was actually trying to open the Directory.

Usual problem. Don't ignore the count returned by read().
while ((count = in,read(buffer)) > 0)
{
out.write(buffer, 0, count);
}
EDIT Your directory problem is cured by:
dir.getParentFile().mkdirs();
and removing the redundant existence check. At present you are creating the file itself as a directory.

storage/emulated/0/ open faild:ENOENT (no such file or directory)?

i have below code that work in some phone and dont work in some other phone.
my code is for saving an image.
String path = Environment.getExternalStorageDirectory().toString();
path += "/";
File fff=new File(path + "/xalopex/Mobile/");
if (!fff.exists())
fff.mkdirs();
path += "xalopex/Mobile/";
path += "lg";
File filename;
try {
filename = new File(path + ".jpg");
FileOutputStream out = new FileOutputStream(filename);
MyImageBitMap.compress(Bitmap.CompressFormat.JPEG, 90, out);
out.flush();
out.close();
MediaStore.Images.Media.insertImage(getContentResolver(),
filename.getAbsolutePath(), filename.getName(),
filename.getName());
} catch (Exception e) {
e.printStackTrace();
//this part will run
// e is storage/emulated/0/xalopex/Mobile/lg.jpg open faild:ENOENT (no such file or directory)
}
where i am wrong ?
How i can fix it?

I would hazard a guess and say its because you need to be accessing /storage/emulated/legacy instead of /storage/emulated/0
I could be wrong.. but I see there are no accepted answers so I'll give this a try :)