Question

I am trying to delete a line from a text file in java, I have read around and it seems that there are a couple of solutions: delete the file and recreate it and write to it, or write to a temp file and rename it. It seems like both solutions involve closing streams, I may be missing something simple here but how do I use a writer with a file after I close it, is there something I can do to get a new writer up and running right after recreating or renaming the file so that I can modify the new file?

For example:

I have a file movies.txt, I save all the lines in that file to a variable, close the streams on movies.txt, delete movies.txt and create movies.txt, how can I write to the new movies.txt after I closed the stream to it?

Or if I rename the file:

I have movies.txt, I create temp.txt and write everything from movies.txt to temp.txt, close streams on movies.txt, rename temp.txt to movies.txt, how do I write to movies.txt if the streams are closed?

Answer 1

Your temp file method might be easier.
Say you want to delete the n-th line from a file, here are the steps you want to follow.

• Create a reader for the target file
• Create a writer to a temp file
• Read each line from source file and write to temp file <— do this n-1 times
• Skip n-th line
• Read each line from source file and write to temp file till end of source file.
• Close source file reader and temp file writer.
• Delete source file and rename temp file to source file’s name.