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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.

Copy directory and everything inside it using Files API in Java

Browsing some answers I found that the following line should to the trick:
Files.copy(Paths.get(from), Paths.get(to),StandardCopyOption.REPLACE_EXISTING);
However, when I actually do provide some directory paths I get various exceptions or nothing is actually being copied, like for example:
kopiraj("C:/Users/Aleksije/Desktop/Rokovi/Rokovi 2016","C:/Users/Aleksije/Desktop/OVDE");
P.S. kopiraj(..) is a method in another class
public void kopiraj(String from, String to) throws IOException {
long t1 = System.nanoTime();
Files.copy(Paths.get(from), Paths.get(to),StandardCopyOption.REPLACE_EXISTING); //the line that matters
proteklo = t1 - System.nanoTime();
traverse(to);
}

After some reading I found that:
You can copy a file or directory by using the copy(Path, Path,
CopyOption...) method. The copy fails if the target file exists,
unless the REPLACE_EXISTING option is specified.
Directories can be copied. However, files inside the directory are not
copied, so the new directory is empty even when the original directory
contains files.
Thus I had to modify my approach to work as follows:
public void kopiraj(String from, String to) throws IOException {
File[] sadrzaj = new File(from).listFiles();
for(File f : sadrzaj) {
if(f.isFile()) {
sviFajlovi.add(f);
Files.copy(Paths.get(f.getAbsolutePath()), Paths.get(to + f.getName()), StandardCopyOption.REPLACE_EXISTING);
} else {
Files.copy(Paths.get(f.getAbsolutePath()), Paths.get(to + f.getName()), StandardCopyOption.REPLACE_EXISTING);
kopiraj(f.getAbsolutePath() + "/", to + f.getName() + "/");
}
}
}
To clarify for someone that might face the same issue:
Files.copy(Paths.get(f.getAbsolutePath()), Paths.get(to + f.getName()), StandardCopyOption.REPLACE_EXISTING);
When using copy from one directory to another, it is a must to provide the new filename in the destination directory, that's why I added the name of the file that is being copied to the destination. (Otherwise you'll lose your destination folder).
kopiraj(f.getAbsolutePath() + "/", to + f.getName() + "/");
When copying the contents of some sub-directory you usually want to keep the contents in there, thus I call the kopiraj() method with a new destination, which has been updated to copy to the now copied sub-directory.

How to create a text file inside a specific directory?

I am trying to cretae a file SYS_CONFIG_FILE_NAME inside a specific directory SYS_CONFIG_DIR_NAME. using the below posted code, when i run the java program it creates two directories instead of one directory and one text file inside that directory.
The out put of the below code is
SYS_CONFIG/config.txt. But `config.txt` is not a text file it is just a directory named `config.txt`
i referred also to some question in stackoverflow but i could not find a solution. Please let me know what I am missing?
code:
private final static String SYS_CONFIG_DIR_NAME = "SYS_CONFIG";
private final static String SYS_CONFIG_FILE_NAME = "config.txt";
private static File newSysConfigInstance() throws IOException {
// TODO Auto-generated method stub
File f = new File(SYS_CONFIG_FILE_PATH + "/" + SYS_CONFIG_DIR_NAME + "/" + SYS_CONFIG_FILE_NAME);
f.mkdirs();
f.createNewFile();
return f;
}

I would do it that way, you have always to call createNewFile() to create a new instance of the file if it is not created.
File dir = new File(SYS_CONFIG_FILE_PATH, SYS_CONFIG_DIR_NAME);
f.mkdirs(); // this to create the directories need for your path.
File file = new File(dir, SYS_CONFIG_FILE_NAME);
if (file.createNewFile()) {
system.out.prinln("file first created");
}else {
// print a message here
}
return file;

You are telling it to make a directory of the form a/b/c if you want a directory of the form a/b then you should give it the directory you want it to create.
File dir = new File(SYS_CONFIG_FILE_PATH, SYS_CONFIG_DIR_NAME);
f.mkdirs();
return new File(dir, SYS_CONFIG_FILE_NAME);
You don't have to pre-create files before you use them.

Moving files from one directory to another with Java NIO

I am using the NIO libraries but I am getting a strange error when I try to move files from one directory to another.
String yearNow = new SimpleDateFormat("yyyy").format(
Calendar.getInstance().getTime());
try {
DirectoryStream<Path> curYearStream =
Files.newDirectoryStream(sourceDir, "{" + yearNow + "*}");
//Glob for current year
Path newDir = Paths.get(sourceDir + "//" + yearNow);
if (!Files.exists(newDir) || !Files.isDirectory(newDir)) {
Files.createDirectory(newDir);
//create 2014 directory if it doesn't exist
}
}
Iterate over elements that start with "2014" and move them in the new directory (newDir, which is also called 2014)
for (Path p : curYearStream) {
System.out.println(p); //it prints out exactly the files that I need to move
Files.move(p, newDir); //java.nio.file.FileAlreadyExistsException
}
I get the java.nio.file.FileAlreadyExistsException because my folder (2014) already exists. What I actually want to do is move all the files that start with "2014" INSIDE the 2014 directory.

Better not going back to java.io.File and using NIO instead:
Path sourceDir = Paths.get("c:\\source");
Path destinationDir = Paths.get("c:\\dest");
try (DirectoryStream<Path> directoryStream = Files.newDirectoryStream(sourceDir)) {
for (Path path : directoryStream) {
System.out.println("copying " + path.toString());
Path d2 = destinationDir.resolve(path.getFileName());
System.out.println("destination File=" + d2);
Files.move(path, d2, REPLACE_EXISTING);
}
} catch (IOException ex) {
ex.printStackTrace();
}

Files.move is not equivalent to the mv command. It won't detect that the destination is a directory and move files into there.
You have to construct the full destination path, file by file. If you want to copy /src/a.txt to /dest/2014/, the destination path needs to be /dest/2014/a.txt.
You may want to do something like this:
File srcFile = new File("/src/a.txt");
File destDir = new File("/dest/2014");
Path src = srcFile.toPath();
Path dest = new File(destDir, srcFile.getName()).toPath(); // "/dest/2014/a.txt"

Continue with #Andrew's answer
If we use only Files.move(src, dst, StandardCopyOption.REPLACE_EXISTING); then it will delete source directory because we only provide a directory path not an absolute path of a particular file. So it will also delete a source directory when operation will be done.
Let's say source path is /opt/src which contains a csv files and destination path is /opt/dst and I want to move all files from src to dst and I'm using Files.move(src, dst, StandardCopyOption.REPLACE_EXISTING); this then it will move all the files to dst but it will delete a src directory after moving all files because we didn't provide an absolute path of a each file for src as well as dst. We should have to provide src path like /opt/src/foo.csv and dst path like /opt/dst/foo.csv then and then it will not delete a source directory.
DirectoryStream used to iterate over the entries in a directory. A directory stream allows for the convenient use of the for-each construct to iterate over a directory. So we get an absolute path for src and we use resolve method for resolving an absolute path for dst.
Please refer DirectoryStream for more information.

Try this code:
public class App
{
public void moveFromSourceToDestination(String sourceName,String destinationName)
{
File mydir = new File(sourceName);
if (mydir.isDirectory())
{
File[] myContent = mydir.listFiles();
for(int i = 0; i < myContent.length; i++)
{
File file1 = myContent[i];
file1.renameTo(new File(destinationName+file1.getName()));
}
}
}
public static void main(String [] args)
{
App app = new App();
String sourceName = "C:\\Users\\SourceFolder";
String destinationName = "C:\\Users\\DestinationFolder\\";
app.moveFromSourceToDestination(sourceName,destinationName);
}
}

Using java.io.File, its as simple as this:
File srcFile = new File(srcDir, fileName);
srcFile.renameTo(new File(destDir, "a.txt"));

How to create a directory in Java?

How do I create Directory/folder?
Once I have tested System.getProperty("user.home");
I have to create a directory (directory name "new folder" ) if and only if new folder does not exist.

new File("/path/directory").mkdirs();
Here "directory" is the name of the directory you want to create/exist.

After ~7 year, I will update it to better approach which is suggested by Bozho.
File theDir = new File("/path/directory");
if (!theDir.exists()){
theDir.mkdirs();
}

With Java 7, you can use Files.createDirectories().
For instance:
Files.createDirectories(Paths.get("/path/to/directory"));

You can try FileUtils#forceMkdir
FileUtils.forceMkdir("/path/directory");
This library have a lot of useful functions.

mkdir vs mkdirs
If you want to create a single directory use mkdir
new File("/path/directory").mkdir();
If you want to create a hierarchy of folder structure use mkdirs
new File("/path/directory").mkdirs();

Create a single directory.
new File("C:\\Directory1").mkdir();
Create a directory named “Directory2 and all its sub-directories “Sub2″ and “Sub-Sub2″ together.
new File("C:\\Directory2\\Sub2\\Sub-Sub2").mkdirs()
Source: this perfect tutorial , you find also an example of use.

For java 7 and up:
Path path = Paths.get("/your/path/string");
Files.createDirectories(path);
It seems unnecessary to check for existence of the dir or file before creating, from createDirectories javadocs:
Creates a directory by creating all nonexistent parent directories first. Unlike the createDirectory method, an exception is not thrown if the directory could not be created because it already exists.
The attrs parameter is optional file-attributes to set atomically when creating the nonexistent directories. Each file attribute is identified by its name. If more than one attribute of the same name is included in the array then all but the last occurrence is ignored.
If this method fails, then it may do so after creating some, but not all, of the parent directories.

The following method should do what you want, just make sure you are checking the return value of mkdir() / mkdirs()
private void createUserDir(final String dirName) throws IOException {
final File homeDir = new File(System.getProperty("user.home"));
final File dir = new File(homeDir, dirName);
if (!dir.exists() && !dir.mkdirs()) {
throw new IOException("Unable to create " + dir.getAbsolutePath();
}
}

Neat and clean:
import java.io.File;
public class RevCreateDirectory {
public void revCreateDirectory() {
//To create single directory/folder
File file = new File("D:\\Directory1");
if (!file.exists()) {
if (file.mkdir()) {
System.out.println("Directory is created!");
} else {
System.out.println("Failed to create directory!");
}
}
//To create multiple directories/folders
File files = new File("D:\\Directory2\\Sub2\\Sub-Sub2");
if (!files.exists()) {
if (files.mkdirs()) {
System.out.println("Multiple directories are created!");
} else {
System.out.println("Failed to create multiple directories!");
}
}
}
}

Though this question has been answered. I would like to put something extra, i.e.
if there is a file exist with the directory name that you are trying to create than it should prompt an error. For future visitors.
public static void makeDir()
{
File directory = new File(" dirname ");
if (directory.exists() && directory.isFile())
{
System.out.println("The dir with name could not be" +
" created as it is a normal file");
}
else
{
try
{
if (!directory.exists())
{
directory.mkdir();
}
String username = System.getProperty("user.name");
String filename = " path/" + username + ".txt"; //extension if you need one
}
catch (IOException e)
{
System.out.println("prompt for error");
}
}
}

Just wanted to point out to everyone calling File.mkdir() or File.mkdirs() to be careful the File object is a directory and not a file. For example if you call mkdirs() for the path /dir1/dir2/file.txt, it will create a folder with the name file.txt which is probably not what you wanted. If you are creating a new file and also want to automatically create parent folders you can do something like this:
File file = new File(filePath);
if (file.getParentFile() != null) {
file.getParentFile().mkdirs();
}

This the way work for me do one single directory or more or them:
need to import java.io.File;
/*enter the code below to add a diectory dir1 or check if exist dir1, if does not, so create it and same with dir2 and dir3 */
File filed = new File("C:\\dir1");
if(!filed.exists()){ if(filed.mkdir()){ System.out.println("directory is created"); }} else{ System.out.println("directory exist"); }
File filel = new File("C:\\dir1\\dir2");
if(!filel.exists()){ if(filel.mkdir()){ System.out.println("directory is created"); }} else{ System.out.println("directory exist"); }
File filet = new File("C:\\dir1\\dir2\\dir3");
if(!filet.exists()){ if(filet.mkdir()){ System.out.println("directory is created"); }} else{ System.out.println("directory exist"); }

if you want to be sure its created then this:
final String path = "target/logs/";
final File logsDir = new File(path);
final boolean logsDirCreated = logsDir.mkdir();
if (!logsDirCreated) {
final boolean logsDirExists = logsDir.exists();
assertThat(logsDirExists).isTrue();
}
beacuse mkDir() returns a boolean, and findbugs will cry for it if you dont use the variable. Also its not nice...
mkDir() returns only true if mkDir() creates it.
If the dir exists, it returns false, so to verify the dir you created, only call exists() if mkDir() return false.
assertThat() will checks the result and fails if exists() returns false. ofc you can use other things to handle the uncreated directory.

This function allows you to create a directory on the user home directory.
private static void createDirectory(final String directoryName) {
final File homeDirectory = new File(System.getProperty("user.home"));
final File newDirectory = new File(homeDirectory, directoryName);
if(!newDirectory.exists()) {
boolean result = newDirectory.mkdir();
if(result) {
System.out.println("The directory is created !");
}
} else {
System.out.println("The directory already exist");
}
}

Here is one attractiveness of the java, using Short Circuit OR '||', testing of the directory's existence along with making the directory for you
public File checkAndMakeTheDirectory() {
File theDirectory = new File("/path/directory");
if (theDirectory.exists() || theDirectory.mkdirs())
System.out.println("The folder has been created or has been already there");
return theDirectory;
}
if the first part of the if is true it does not run the second part and if the first part is false it runs the second part as well

public class Test1 {
public static void main(String[] args)
{
String path = System.getProperty("user.home");
File dir=new File(path+"/new folder");
if(dir.exists()){
System.out.println("A folder with name 'new folder' is already exist in the path "+path);
}else{
dir.mkdir();
}
}
}