Quick Answer: 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 delete a specific line from a text file in Java?

Deleting a text line directly in a file is not possible. We have to read the file into memory, remove the text line and rewrite the edited content.

There is no magic to removing lines.

  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 change the first line of a text file in Java?

First use BufferedReader ‘s readLine() to read the first line. Modify it and write it to the BufferedWriter . Then use a char[] array to perform a brute-force copy of the remainder of the file. This will be more efficient than doing the copy line by line.

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How do I delete a single line in a text file?

The best way to do this is to open the file in text mode, read each line with ReadLine(), and then write it to a new file with WriteLine(), skipping the one line you want to delete.

How do you delete a text file in Java?

In Java, we can delete a file by using the File. delete() method of File class. The delete() method deletes the file or directory denoted by the abstract pathname. If the pathname is a directory, that directory must be empty to delete.

What is 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 remove the last line of a file in Java?

If you wanted to delete the last line from the file without creating a new file, you could do something like this: RandomAccessFile f = new RandomAccessFile(fileName, “rw”); long length = f.

How do you overwrite a line in a text file in Java?

Invoke the replaceAll() method on the obtained string passing the line to be replaced (old line) and replacement line (new line) as parameters. Instantiate the FileWriter class. Add the results of the replaceAll() method the FileWriter object using the append() method.

How do you replace a line in a file in Linux?

The procedure to change the text in files under Linux/Unix using sed:

  1. Use Stream EDitor (sed) as follows:
  2. sed -i ‘s/old-text/new-text/g’ input. …
  3. The s is the substitute command of sed for find and replace.
  4. It tells sed to find all occurrences of ‘old-text’ and replace with ‘new-text’ in a file named input.
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How do you add a line at the beginning of a file in Java?

The only way to insert a line in a text file is to read the original file and write the content in a temporary file with the new line inserted. Then we erase the original file and rename the temporary file to the original name.

How do you delete a specific line in a file in C?

Delete from a text file using C

  1. #include<stdio.h>
  2. int main(){
  3. FILE *fptr1, *fptr2;
  4. char file1[] =”file1.txt”;
  5. char file2[] =”file2.txt”;
  6. char curr;
  7. int del, line_number = 0;
  8. printf(“Please enter the line number you want to delete : “);

How do you delete a line in terminal?

Deleting a Line

  1. Press the Esc key to go to normal mode.
  2. Place the cursor on the line you want to delete.
  3. Type dd and hit Enter to remove the line.

How do you remove a single line from a text file in Unix?

To Remove the lines from the source file itself, use the -i option with sed command. If you dont wish to delete the lines from the original source file you can redirect the output of the sed command to another file.

How do you clear a line in Java?

Use ANSI Escape Codes to Clear Console in Java

To clear the console in Java, we will use the escape code 33[H 33[2J . This weird set of characters represents the command to clean the console.

How do you edit a text file in Java?

Modify a . txt 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.
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How do you rewrite a text file in Java?

Is this the best way to rewrite the content of a file in Java?

  1. Save the file name.
  2. Delete the existing file.
  3. Create a new empty file with the same name.
  4. Write the desired content to the empty file.
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