Java how to create, open, write, and read then close the file -


so here's problem, stack on how create, open, write, , read file, code

import java.util.*; import java.io.*;  class class_name{  formatter x;                       // variable: creating new file file file = new file("file.txt");  // variable: check file existence      //creating txt file     public void creating_file(){         try{             x = new formatter("file.txt");         }catch(exception e){             system.out.println("you got error");         }     }      public int check_file(){         if(file.exists()){             return 1; // in main method, check if file exists pass creating file         }else{             return 0; // in main method if return value 0, create new file "public void creating_file()" method         }     }

so problem when tried write in file, using class formatter , format text data in before , class formatter won't work if public int check_file() equals 1 because skip creating file using formatter class , can't write in file because variable x undefined

this code how write text in file

    public void recording_to_file(){         x.format(format, args);      }

and closing file need handle error this

    public void close_file(){         try{             x.close();         }catch(exception e){             file.close();         }     }  }

there ton of class need 1 file, or maybe there 1 simple class can in 1 like(write, open, read, close), new in java, think maybe in here can help, thank you

take @ this. second argument filewriter costructor (true) tells append data, instead of overwriting any.

import java.util.*; import java.io.*;  class someclass{      formatter x;                            file file = new file("file.txt");        public void creating_file(){         try{             x = new formatter(new filewriter(file, true));         }catch(exception e){             system.out.println("you got error");         }     }      public boolean check_file(){         return file.exists();     } }

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