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How to clear a text file in java?

  1. Using java. io. File. delete() function: Deletes the file or directory denoted by this abstract path name. Syntax: public boolean delete() Returns: true if and only if the file or directory is successfully deleted; false otherwise.
  2. Using java. nio. file. files.

How do you delete a specific line from a text file in Java?

  1. Copy the file line by line, without the line you don’t want.
  2. Delete the original file.
  3. rename the copy as the original file.

How do I delete a text file?

  1. file = open(“sample.txt”,”r+”)
  2. file. truncate(0)
  3. file.

How do I delete a file in a directory in Java?

  1. Provide the path of a directory.
  2. Call user-defined method deleteDirectory() to delete all the files and subfolders.

Is file empty Java?

Well, it’s pretty easy to check emptiness for a file in Java by using the length() method of the java. io. File class. This method returns zero if the file is empty, but the good thing is it also returns zero if the file doesn’t exist.

How do I remove the first line of a text file in Java?

Scanner fileScanner = new Scanner(myFile); fileScanner. nextLine(); This will return the first line of text from the file and discard it because you don’t store it anywhere.

How do you manipulate a text file in Java?

Step 1 : Create a File object by passing the path of the file to be modified. Step 2 : Initialize oldContent with an empty string. This String object will hold all the old content of the input text file. Step 3 : Create BufferedReader object to read the input text file line by line.

How do you edit a text file in Java?

  1. Open the existing file using a BufferedReader.
  2. Read each line, make modifications to each line, and add it to a StringBuilder.
  3. Once all the text has been read and modified, write the contents of the StringBuilder to a new file.
  4. Replace the old file with the new file.

What is the use of flush method in Java?

The flush() method of PrintWriter Class in Java is used to flush the stream. By flushing the stream, it means to clear the stream of any element that may be or maybe not inside the stream. It neither accepts any parameter nor returns any value.

How do you nullify a file?

  1. Empty File Content by Redirecting to Null.
  2. Empty File Using ‘true’ Command Redirection.
  3. Empty File Using cat/cp/dd utilities with /dev/null.
  4. Empty File Using echo Command.
  5. Empty File Using truncate Command.

How do you remove something from a text file in Python?

  1. a_file = open(“sample.txt”, “r”) get list of lines.
  2. lines = a_file. readlines()
  3. a_file.
  4. del lines[1] delete lines.
  5. new_file = open(“sample.txt”, “w+”) write to file without line.
  6. for line in lines:
  7. new_file. write(line)
  8. new_file.

How do you clear a log file?

  1. Check the disk space from the command line. Use the du command to see which files and directories consume the most space inside of the /var/log directory.
  2. Select the files or directories that you want to clear:
  3. Empty the files.

How do you change a filename in Java?

  1. Create an object of the File class and replace the file path with the path of the directory.
  2. Create another object of the File class and replace the file path with the renaming path of the directory.
  3. Use renameTo() method.
  4. If rename operation successful then the function returns true.
  5. Else returns false.

How can we delete all files in a directory?

  1. -r : Remove directories and their contents recursively.
  2. -f : Force option.
  3. -v : Verbose option.

How do you use mkdir in Java?

File mkdir() method in Java with examples The mkdir() method is a part of File class. The mkdir() function is used to create a new directory denoted by the abstract pathname. The function returns true if directory is created else returns false. Parameters: This method do not accepts any parameter.