文件到2d数组打印null(Java)

时间:2015-01-21 19:17:07

标签: java printing null multidimensional-array

我目前正在开发一款游戏,现在(在游戏中)是一名关卡编辑/读者。我这样做的方法是将级别存储在txt文件中,然后将txt文件输入缓冲区读取器,然后将文本文件放入2d数组,如[lines] [words]。我的意思是我希望第一个方括号中的数字表示你想要的行(来自文件),然后用另一个方括号从该行中选择一个单词。

我打印文件并将其存储在一个类中的二维数组中,但当我尝试将信息传输到另一个类时,如下所示:String strLevel = TextHandler.getLevel("res/levels.txt")
然后,当我尝试打印strLevel [1] [1]时,它只是在控制台中打印出null(s)...

以下是TextHandler.java的代码:

公共类TextHandler {

final static int LEVELS = Level.LEVEL_AMOUNT;
final static int MAX_LINES = 100;
final static int MAX_WORDS = 100;



public static String[][] getLevel(String path) throws IOException {
    int x = 0;
    int y = 0;

    String lines[][] = new String[MAX_LINES][MAX_WORDS];


    BufferedReader in = new BufferedReader(new FileReader(path));

    String line;

    while ((line = in.readLine()) != null)  //file reading
    {
       String[] values = line.split(" ");

       for (String str : values){   
           lines[x][y] = str;
           System.out.print(lines[x][y] + " ");    //This print funciton works!

           y += 1; 
       }

       x += 1;
       System.out.println("");
    }


    return lines;
}

}

这是文本文件:

  

等级0
  添加TYPE_WALL 100 300 400 100
  添加TYPE_WALL 200 300 200 50
  添加TYPE_WALL 400 53 800 10
  添加TYPE_PLAYER 200 40

     

等级1   添加TYPE_WALL 100 300 400 100
  添加TYPE_WALL 200 300 200 50
  添加TYPE_WALL 400 53 800 10
  添加TYPE_PLAYER 100 200

     

2级      //空水平

     

等级3      //空水平

     

等级4      //空水平

     

等级5      //空水平

     

等级6      //空水平

这是结果:

  

等级0
  添加TYPE_WALL 100 300 400 100
  添加TYPE_WALL 200 300 200 50
  添加TYPE_WALL 400 53 800 10
  添加TYPE_PLAYER 200 40

     

等级1   添加TYPE_WALL 100 300 400 100   添加TYPE_WALL 200 300 200 50   添加TYPE_WALL 400 53 800 10   添加TYPE_PLAYER 100 200

     

等级2

     

等级3

     

等级4

     

等级5

     

等级6   空
  空
  空
  空
  空
  空
  空
  空
  空
  null

正如我之前所说,问题是当我尝试制作一个等于getLevel的二维数组('路径')然后打印它时,它会打印" null"! !

这是一些Level类代码:

package com.sontvedt.engine;

import java.io.IOException; import java.util.ArrayList;

import com.sontvedt.entity。*;

公共班级{

Utilities util = new Utilities();
TextHandler txt = new TextHandler();

static final int LEVEL_AMOUNT = 10;

String strLevel[][];

Player player;
Wall wall = new Wall(42,42,42,42);

ArrayList<Entity> objects = new ArrayList<Entity>();
Enemy[] enemies = new Enemy[20];        //This it later going to be added in the entities arrayList. The reason its a normal array is so that it would work with collision detection



//Pre-init of the levelAmount should be done here
public Level(){
    player = new Player(42, 42);

    try {
        strLevel = TextHandler.getLevel("res/levels.txt");
    } catch (IOException e) {
        e.printStackTrace();
    }



    //Init entities ArrayList       
        createLevels(0);

}

//Collision check
public void update(){
}


/*  LEVEL CREATION
 * 
 * The first thing that is going to be in the "level editor" text file
 * is which level the items are going to be added to. Like so:
 *      - level 0
 * 
 * The entity adding is later going to be added in a text file as so:
 *      - Group entity xPos yPos Width Height
 *      - enemies enemy 60 60, 200, 100
 * 
 * The player postition is the first two numbers in txt file,
 * Player is also the last item that should be added to entities
 * 
 * This may have to be in the end of the superloop
 *          
 * for(int i = 0; i < enemies.length; i++)
 *      entities[level].add(enemies[i]);
 * 
 */

public void createLevels(int level){
    objects.add(player);
    objects.add(wall);          

    //Should print add from text file/TextHandler.getLevel()
    System.out.println(strLevel[1][1]);


    for(int i = 0; i >= TextHandler.MAX_LINES; i++){
        for(int j = 0; j >= TextHandler.MAX_WORDS; j++){

            if(strLevel[j][j] == "level"){
                System.out.println("I found the word 'level', I'm so cool, look at meee... :P");
            }
        }
    }   
}

很长一段时间以来一直在寻找答案,但我一无所获......请尽快帮助!

1 个答案:

答案 0 :(得分:1)

到达新行时,您不会重置y值:

while ((line = in.readLine()) != null)  //file reading
{
   String[] values = line.split(" ");
   y=0; // gotta start back at 0 when we get to a new line

其他内容

//Should print add from text file/TextHandler.getLevel()
System.out.println(strLevel[1][1]);

评论不正确,应打印TYPE_WALL。


if(strLevel[j][j] == "level"){

使用.equals而非==比较字符串,以进行空安全比较:

if("level".equals(strLevel[j][j]))

if(strLevel[j][j] == "level"){

我非常确定你的意思是strLevel[i][j],也因为你在其他地方使用xy,你应该尽量保持一致。也许将i重命名为x,将j重命名为y