无法从Java中的文本文件读取和排序信息

Question

I'm attempting to read a text file using BufferedReader and sort the information within the file. The purpose is to load and be able to access information on maps for a game I'm making. The problem I have is that when my program tried to sort the information I get a NullPointerException .

LoadWorld.java:

public class LoadWorld {

    private static String CurrentString;
    private static String[] LinePts;
    private static String Path="";
    private static String Name="";
    private static String Auth="";
    private static String Date="";

    private static boolean Reading = true;
    private static boolean OnMap = false;

    private static int Maps = 0;

    private static Map[] Map;

    public static void Load() {

         try {

                BufferedReader reader = 
                    new BufferedReader(new InputStreamReader(LoadWorld.class.getResourceAsStream("/Maps/Maps.txt")));

                while(Reading) {

                    CurrentString = reader.readLine();

                    if (CurrentString.equals("{")) {OnMap=true;Maps+=1;}
                    else {Reading=false;}

                    while(OnMap) {



                        CurrentString = reader.readLine();
                        if (!(CurrentString.equals("}"))) {

                            LinePts = CurrentString.split("-");

                            if (LinePts[0].equals("PATH")) {Path=LinePts[1];}
                            else if (LinePts[0].equals("NAME")) {Name=LinePts[1];}
                            else if (LinePts[0].equals("AUTH")) {Auth=LinePts[1];}
                            else if (LinePts[0].equals("DATE")) {Date=LinePts[1];}

                        }
                        else {

                            Map[Maps].Path = Path;
                            Map[Maps].Name = Name;
                            Map[Maps].Auth = Auth;
                            Map[Maps].Date = Date;
                            OnMap=false;

                        }

                    }

                }

                reader.close();         
            }

            catch(IOException e) {

                e.printStackTrace();

            }

    }

The problem occurs in the "else{" section, at "map[maps].path = path;".

Map.java:

public class Map {

    public String Path;
    public String Name;
    public String Auth;
    public String Date;
    public String Map;

}

The text file I'm attempting to read: Maps.txt

{
PATH-Default/Basic.txt
NAME-Basic Map
AUTH-Aelex Esrom
DATE-11/1/15
}

Any help is appreciated! Thanks in advance for any answers.

Answer 1

you need to initialize your variable Map

Map = new Map[5]; //array of fixed size 5

perhaps you are trying to dynamically add array elements the PHP way but it does not work the same way in Java. You will either create an array of a fixed size or use ArrayList