Java Create File If Not Exists

In Java, we can use the NIO Files.createDirectory to create a directory or Files.createDirectories to create a directory including all nonexistent parent directories.

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1. Create Directory – Java NIO

1. How to create a file if it does not exist in java. Java create a file if it doesn't exist and write. 'javadoc' error FileNotfoundException: does not exist. Java read file create if not exist. Create new file if not exists java. Java fileinputstream create new file.
2. CREATENEW – Creates a new file and throws an exception if the file already exists. CREATE – Opens the file if it exists or creates a new file if it does not. DELETEONCLOSE – Deletes the file when the stream is closed. This option is useful for temporary files. SPARSE – Hints that a newly created file will be sparse.
3. Nov 18, 2017 You can create an empty file whether it exists or not new FileOutputStream('score.txt', false).close; if you want to leave the file if it exists new FileOutputStream('score.txt', true).close; You will only get a FileNotFoundException if you try to create the file in a directory which doesn't exist.

Oct 06, 2021 File exists method in Java with examples. The exists function is a part of the File class in Java. This function determines whether the is a file or directory denoted by the abstract filename exists or not. The function returns true if the abstract file path exists or else returns false.

1.1 We can use Files.createDirectory to create a directory.

• If the parent directories not exist, throws NoSuchFileException.
• If the directory exists, throws FileAlreadyExistsException.
• If IO errors, throws IOException.

1.2 We can use Files.createDirectories creates a directory including all nonexistent parent directories.

• If the parent directories not exist, create it first.
• If the directory exists, no exception thrown.
• If IO errors, throws IOException

1.3 This example uses Files.createDirectories to create a directory /test4/ including all nonexistent parent directories /test2/test3/.

2. Create Directory – Legacy IO

For legacy IO java.io.File, the similar methods are file.mkdir() to create a directory, and file.mkdirs() to create a directory including all nonexistent parent directories.

Both file.mkdir() and file.mkdirs() returns a boolean, true if success to create the directory, fail otherwise, no exception thrown.

In legacy IO, the lack of exception thrown in creating directory makes developers very hard to debug or understand why we cannot create a directory, and this is one of the reasons Java releases a new java.nio.Files to throw a proper exception.

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$ git clone https://github.com/mkyong/core-java

$ cd java-io

References

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Comments

I want to check the Folder Existance before creating the new one. For that which method I need to use :

there are two method for checking the same
1) folder.getAbsoluteFile().exists() OR
2) folder.exists()

Which one to use?

Thanks for looking here.

First of all read Oracle docks on exists. And getAbsoluteFile.

Answer yourself what does getAbsoluteFile do? Then answer yourself do you need to get the absolute form of of your folder abstract pathname? Does it help you in anything?

If not, use simpliest easy to write easy to read method folder.exists().

In coding we are always trying not to do unneccesary thing, to keep our code fast, clean, readable, easy to understand and update.

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On the link you post, I see a class like below. Create this class in your project before using it. private class AsyncCallWS extends AsyncTask { @Override protected Void doInBackground(String.. params) { Log.i(TAG, 'doInBackground'); getFahrenheit(celcius); return null; } @Override protected void onPostExecute(Void result) { Log.i(TAG, 'onPostExecute'); tv.setText(fahren +..

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Math.floor(x+0.7) should do it. This should work for an arbitrary mantissa. Just add the offset to the next integer to your value and round down. The rounding is done by floor. Here is what the java API says to floor: Returns the largest (closest to positive infinity) double value that..

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I'm sad that this question hasn't been answered, and upon that, I can't upvote it from it's -8 cause I don't have enough reputation. It seems downvoting is getting too unwarranted here. OP is just looking for an answer, which can be answered here and found online, he has tried..

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-0777 is treated by the compiler as an octal number (base 8) whose decimal value is -511 (-(64*7+8*7+7)). -777 is a decimal number.

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After super.onCreate(savedInstanceState); insert setContentView(R.layout.YourLayout); you need to make a request to a server in another thread. It might look like public class LoginTask extends AsyncTask{ private String username; private String password; private Context context; public LoginTask(Context context, String username, String password) { this.username = username; this.password = password;..

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