java io - File output deletes all the content -


i trying make program removes text file. text remove , file path provided command line arguments. goes fine, when open file after program has finished running, it's empty. doing wrong?

import java.io.file; import java.io.ioexception; import java.io.printwriter; import java.util.scanner;  public class remove { public static void main(string[] args) throws ioexception{     if(args.length != 2) {         system.out.println("usage : java remove stringtoremove filepath");         system.exit(1);     }     string stringtoreplace = args[0];     string path = args[1];     file file = new file(path);     if(!file.exists()) {         system.out.println("no such file exists!");         system.exit(2);     }      scanner input = new scanner(file);     printwriter output = new printwriter(file);      while(input.hasnext()) {         string currentline = input.nextline();         currentline = currentline.replaceall(stringtoreplace, "");         output.println(currentline);     }      input.close();     output.close();      system.out.println("operation successful"); } }

opening file writing clears file, if input , output files same, input cleared , nothing happen because there no lines.


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