java - NumberFormatExceptions being thrown everywhere. Why? (parseInt) -

first time poster here annoying issue. have decided create text-based rpg in java in order consolidate have been learning. , lengthy games, saving/loading system necessary. problems arise.

i have created menu system, works fine. however, when decide start new game, numberformatexceptions thrown left, right , center. source code down below, @ appreciated. have separated each important section separate java files.

//imports import java.io.ioexception; import java.io.file; import java.io.*; import java.util.scanner; import javax.sound.sampled.audioinputstream; import javax.sound.sampled.audiosystem; import javax.sound.sampled.clip;  //'choices' - yemi oladimeji/yemzeee  class choices{         public static void main(string [] args) throws ioexception{      scanner input = new scanner(system.in);     string startchoice = null;      //introduction begin         gamemethods.space();         system.out.println("########  ##    ## ######## ######## ########            ######## ########");         system.out.println("##        ##    ## ##    ##    ##    ##       ##       ##        ");         system.out.println("##        ##    ## ##    ##    ##    ##       ##       ##        ");         system.out.println("##        ######## ##    ##    ##    ##       ######    ###### ");         system.out.println("##        ##    ## ##    ##    ##    ##       ##             ##");         system.out.println("##        ##    ## ##    ##    ##    ##       ##             ##");         system.out.println("########  ##    ## ######## ######## ######## ######## ########");         gamemethods.space();         system.out.println("greetings, , welcome choices, 2d text-based rpg!");         system.out.println("what do?");         system.out.println("<p>lay :: <a>bout :: <q>uit");         startchoice = input.nextline();         gamemethods.schoice(startchoice);         } }//end choices.java 

this beginning of gamemethods.java file

import java.util.scanner; import java.io.*; import java.io.ioexception;  public class gamemethods extends choicesavemethods{  static scanner input = new scanner(system.in); static string startchoice; static string loadchoice;  public static void buffer(){     try{         system.in.read();         } catch(exception e){     } }  public static void space(){     system.out.println(" "); }  public static void quit(){ system.exit(1); }  public static void menucall(){     system.out.println("<p>lay :: <a>bout :: <q>uit");     startchoice = input.nextline();     gamemethods.schoice(startchoice); }  public static void schoice(string startchoice){     if(startchoice.equals("a")){         gamemethods.space();         system.out.println("this text-based rpg, created yemi oladimeji.");         system.out.println("it focuses on story , said story changes depend on \nthe choices make in world.");         system.out.println("as quite story driven, there option @ \nthe end of journey output story text file save , keep.");         system.out.println("now know game about, want go menu? \n(y/n)");         string achoice = input.nextline();         if(achoice.equals("y")){             gamemethods.menucall();         } else if(achoice.equals("n")){             system.out.println("or quit game?");             string qchoice = input.nextline();             if(qchoice.equals("y")){                 system.exit(1);             } else if(qchoice.equals("n")){                 gamemethods.menucall();             }         }        }     if(startchoice.equals("q")){         gamemethods.quit();     }     if(startchoice.equals("p")){         try{             bufferedreader savefile = new bufferedreader(new    filereader("c:\\users\\yemi\\desktop\\thegame\\savefiles\\textsave1.txt"));             areamarkers[0] = integer.parseint(savefile.readline());             areamarkers[1] = integer.parseint(savefile.readline());             areamarkers[2] = integer.parseint(savefile.readline());             areamarkers[3] = integer.parseint(savefile.readline());             savefile.close();                  for(int x = 0; x < 4; x++){                 if(areamarkers[x] == 1){                     system.out.println("a save game has been located. load it?(y/n)");                     loadchoice = input.nextline();                     if(loadchoice.equals("y")){                         system.out.println("the save/load feature works.");                     } else if(loadchoice.equals("n")){                         system.out.println("starting new game...");                         gamemethods.gamestart();                     }                 }             }         } catch(ioexception ex){             ex.printstacktrace();         }         forestarea();     } }  public static void gamestart(){     //introduction begin         gamemethods.space();         system.out.println("welcome 'choices'. influence world decisions. react \nhow wish...");         gamemethods.space();         system.out.println("this game built immerse in hooking storyline no graphics, \nand imagination can that. \nthat , audio. purpose, recommend use headphones \nwhilst playing game.");         system.out.println("i require 2 pieces of information. name. it?\n(this called in game)");         system.out.println("your name: ");         string name1 = input.nextline();         system.out.println("and name user account\n(so program can locate required files): ");         string username = input.nextline();         system.out.println("there 2 rules...");         system.out.println("this (*) means flashback occurring.");         system.out.println("and when there pause, means \nshould press enter/return continue.");         system.out.println("you that? good.");         system.out.println("now. let begin game , remember. \nyour     choices affect path.");     //introduction end } } 

and last java file, 1 contains areas , saving method:

import java.io.*; import java.util.scanner; import java.io.ioexception;  public class choicesavemethods{  //area variables: static int[] areamarkers = new int[4]; static int[] areachoices = new int[4]; static scanner input = new scanner(system.in);   public static void forestarea(){     gamemethods.space();     system.out.println("area 1: forest. here?: ");     system.out.println("1 - save game?");     system.out.println("2 - view description of area?");     system.out.println("3 - progress next area?");     system.out.println("4 - exit main menu?");     areachoices[0] = input.nextint();     if(areachoices[0] == 1){         try{             filewriter savefile1 = new filewriter("c:\\users\\yemi\\desktop\\thegame\\savefiles\\textsave1.txt");             areamarkers[0] = 1;             savefile1.write(1);             system.out.println("game has been saved successfully.");             savefile1.close();             forestarea();         } catch (ioexception ex){             ex.printstacktrace();         }      } else if(areachoices[0] == 2){         system.out.println("this forest. has trees.");         forestarea();     } else if(areachoices[0] == 3){         system.out.println("progressing next area...");         cityarea();     } else if(areachoices[0] == 4){         system.out.println("returning main menu.");         gamemethods.menucall();     } }  public static void cityarea(){     gamemethods.space();     system.out.println("area 2: city. here?: ");     system.out.println("1 - save game?");     system.out.println("2 - view description of area?");     system.out.println("3 - progress next area?");     system.out.println("4 - exit main menu?");      areachoices[1] = input.nextint();      if(areachoices[1] == 1){         try{             filewriter savefile2 = new filewriter("c:\\users\\yemi\\desktop\\thegame\\savefiles\\textsave1.txt");             areamarkers[1] = 1;             savefile2.write(areamarkers[1]);             system.out.println("game has been saved successfully.");             savefile2.close();             cityarea();         } catch(ioexception ex){             ex.printstacktrace();         }         } else if(areachoices[1] == 2){             system.out.println("this city. there alot of people.");             cityarea();         } else if(areachoices[1] == 3){             system.out.println("progressing next area...");             magmaarea();         } else if(areachoices[1] == 4){             system.out.println("returning main menu.");             gamemethods.menucall();         } }  public static void magmaarea(){     gamemethods.space();     system.out.println("area 3: magma pool. here?: ");     system.out.println("1 - save game?");     system.out.println("2 - view description of area?");     system.out.println("3 - progress next area?");     system.out.println("4 - exit main menu?");      areachoices[2] = input.nextint();      if(areachoices[2] == 1){         try{             filewriter savefile3 = new    filewriter("c:\\users\\yemi\\desktop\\thegame\\savefiles\\textsave1.txt");             areamarkers[2] = 1;             savefile3.write(areamarkers[2]);             system.out.println("game has been saved successfully.");             savefile3.close();             magmaarea();         } catch(ioexception ex){             ex.printstacktrace();         }     } else if(areachoices[2] == 2){         system.out.println("a blazing pool of molten rock. hot.");         magmaarea();     } else if(areachoices[2] == 3){         system.out.println("progressing next area.");         hospitalarea();     } else if(areachoices[2] == 4){         system.out.println("returning main menu.");         gamemethods.menucall();     } }  public static void hospitalarea(){     gamemethods.space();     system.out.println("area 4: hospital. here?: ");     system.out.println("1 - save game?");     system.out.println("2 - view description of area?");     system.out.println("3 - exit main menu.");      areachoices[3] = input.nextint();      if(areachoices[3] == 1){         try             {             filewriter savefile4 = new filewriter("c:\\users\\yemi\\desktop\\thegame\\savefiles\\textsave1.txt");             areamarkers[3] = 1;             savefile4.write(areamarkers[3]);             system.out.println("game has been saved.");             savefile4.close();             hospitalarea();         } catch(ioexception ex){             ex.printstacktrace();         }     } else if(areachoices[3] == 2){         system.out.println("a disused, abandoned hospital. has eerie feel     it.");         hospitalarea();     } else if(areachoices[3] == 3){         system.out.println("returning main menu...");         gamemethods.menucall();     } } }  

and exception being thrown this:

exception in thread "main" java.lang.numberformatexception: input string: ""     @ java.lang.numberformatexception.forinputstring(numberformatexception.java:65)     @ java.lang.integer.parseint(integer.java:504)     @ java.lang.integer.parseint(integer.java:527)     @ gamemethods.schoice(gamemethods.java:59)     @ choices.main(choices.java:32)     

i realize lot asking for, first time poster, running out of ideas here. feel free copy , run code. answers @ appreciated. again, thank you.

agree jahroy; stack trace telling what's wrong. looking @ code you're trying read 4 integers on 4 lines save file, save logic in *area() methods ever write 1 integer. maybe intended write out integer , 3 zeros instead?

probably better use single integer indicate location in save file (0=forest, 1=city, 2=magma, etc.) rather 4 0/1 ints on separate lines.