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();
}
}
}
Related
I have a folder called "all_users" in my java project under the src directory.How can I access the files(if there are any) in the all_users folder. I eventually want to loop through all the existing files in the "all_users" folder, comparing whether the file name is equal to a string i specify in the code.
Firstly, I tried File f = new File(System.getProperty("user.home")+File.pathSeparator + "all_users"); as the file object then later tried File dir = new File(TEST_PATH); Both returned false when i checked if it existed so i didn't set up the path correctly?
public class ValUtility {
static final String TEST_PATH = "./all_users/";
public static boolean validUsername(String user) {
File f = new File(System.getProperty("user.home") + File.pathSeparator + "all_users");
File dir = new File(TEST_PATH);
File[] directoryListing = f.listFiles();
System.out.println(f.exists());
System.out.println(directoryListing);
if (directoryListing != null) {
for (File child : directoryListing) {
// Do something with child
// think child is filename?
if (user.equals(child.getName())){
return false;
}
}
}
return true;
}
}
Please run...
System.out.println(System.getProperty("user.home"));
The above will inform you where you need to add a folder labeled 'all_users'. It is very unlikely that your 'user.home' property is set to your project's source file (src) folder.
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.
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.
So, I'm having a hard time with files. I've used files before, but this time they are being a pain.
public SaveFile(File newFile)
{
this.file = newFile;
boolean first = false;
if(!file.exists()){
file.mkdir();
first = true;
}
if(file.isDirectory()){
throw new IllegalStateException("Save file can not be a folder");
}
if(file.getName().equalsIgnoreCase("current")){
first = false;
}
this.config = YamlConfiguration.loadConfiguration(this.file);
String name = file.getName();
name = name.substring(0, name.lastIndexOf("."));
if(first){
config.set("name", name);
config.set("health", 20.0F);
config.set("level", 0);
}
try {
config.save(file);
} catch (IOException e) {
e.printStackTrace();
}
}
When I create one save file, it works no problem. I can view and edit the file, which is great. However, if I attempt to create a second SaveFile, it turns the NEW file into a folder and throws an IllegalStateException
This is how it looks:
public static void main(String[] args){
SaveFile robert = new SaveFile(new File(SaveFile.getSaveFolder(), "Robert.save"));
SaveFile james = new SaveFile(new File(SaveFile.getSaveFolder(), "James.save");
}
The SaveFile robert is created, and looks like its supposed to.
The SaveFile james is created as a folder, and throws an IllegalStateException
Apparently you are trying to create a file in a parent directory and you want to check whether the parent directory exists and create it first if required.
You need to get the parent of the file you pass which is the directory you may want to create using File#getParentFile(). This method returns a File object of witch you have to call File#mkdirs().
You could proceed like this for example:
public void saveFile(File newFile)
{
File file = newFile;
if(! file.exists()){
File dir = file.getParentFile();
if(! dir.exists()) {
if(dir.mkdirs()) {
System.out.println("parent directory "
+ dir.getPath() + " created");
}
if(! dir.isDirectory()){
throw new IllegalStateException("Unable to create directory "
+ dir.getPath());
}
}
} else {
if(file.isDirectory()){
throw new IllegalStateException("Save file can not be a folder");
}
}
// ...
System.out.println("Save file " + file.getPath() + " created");
}
I think you're problem is here, as noted in my code comments:
boolean first = false;
if(!file.exists()){
// the following line is turning the file into a directory if the file
// doesn't already exist
file.mkdir();
first = true;
}
// now you are checking if the directory you just created is a directory
// (this will, of course, be true) and thus throw the exception
if(file.isDirectory()){
throw new IllegalStateException("Save file can not be a folder");
}
So it looks like "Robert.save" exists, and thus works, but "James.save" doesn't so it get created as a directory.
It has something to do with this line of code:
file.mkdir();
,which makes a directory out of the path of the File object you pass as parameter. So, if none of the files (Robert.save and James.save) exist before the execution, it will create two directories named /your/path/Robert.save and /your/path/James.save.
The fact that it only creates one directory may only be caused by the fact that Robert.save might already exist before you execute your code. So the mkDir method won't be called because the following condition isn't validated:
if(!file.exists())
I am having an input folder say c:\files\input\ that contains my list of files that I am using.
How do I use the above to create say c:\files\output\ and copy the files from the input folder to the output folder?
My c:\files\input is read from an object, say
String inputFolder = dataMap.getString("folder");// this will get c:\files\input\
You got path of folder in variable inputFolder now do as follows.
String inputFolder = dataMap.getString("folder");
File dir = new File(inputFolder);
if(dir.mkdirs()){
System.out.println("Directory created");
}else{
System.out.println("Directory Not Created");
}
You can use FileUtils from org.apache.commons.io library
FileUtils.copyDirectory(srcDir, destDir);
so in your case:
File file = new File(inputFolder);
String parentDir = file.getParentFile().getAbsolutePath();
File outputDir = new File(parentDir, "output");
if(!outputDir.exsit()) {
outputDir.mkdir();
}
FileUtils.copyDirectory(inputFolder, outputDir);
To Create the directory you can refer to the below code
File file = new File("c:\\files\\output");
if (!file.exists()) {
if (file.mkdir()) {
System.out.println("Directory is created!");
} else {
System.out.println("Failed to create directory!");
}
}
To copy files from a directory to another directory.. refer to the following link it gives a good explanation with source code examples
http://examples.javacodegeeks.com/core-java/io/file/4-ways-to-copy-file-in-java/