为什么我的数组未正确填充？

Question

I am writing code for a game in Java. Specificly I'm working on the level creation using a character array filled by characters from a .txt file. My problem is that the array is not filled as it should be and the final line remains empty. I can't work this out so any kind of help will be gladly accepted, here's the problematic block of code :

public static void main(String[] args) throws IOException{

char background[][] = new char [14][20];

try {

    FileInputStream fileinput = new FileInputStream("background.txt");
        int r;
        for(int i=0;i<=13;i++){
            for(int j=0;j<19;j++){
                while((r = fileinput.read()) != -1){
                    char c = (char) r;
                    background[i][j] = c;
                    break;
                }
            }
        }
        fileinput.close();
    }

    catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    for (int i=0;i<=13;i++){
        for(int j=0;j<=19;j++){
            System.out.print(background[i][j]);
        }
    }
}

Also the code as a whole can be found in the following link: http://pastebin.com/HtwMpsjm Here's the .txt file too!

Answer 1

You accidentally one of your conditions, i've commented on the changed line.

As someone has mentioned in the comments, you might find it beneficial to treat your loops conditions as for(int i=0;i<20;i++) rather than for(int i=0i<=19;i++) it makes the code a little more readable.

public static void main(String[] args) throws IOException{

char background[][] = new char [14][20];

try {

    FileInputStream fileinput = new FileInputStream("background.txt");
        int r;
        for(int i=0;i<=13;i++){
            for(int j=0;j<=19;j++){//<<THIS LINE WAS CHANGED
                while((r = fileinput.read()) != -1){
                    char c = (char) r;
                    background[i][j] = c;
                    break;
                }
            }
        }
        fileinput.close();
    }

    catch (FileNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    for (int i=0;i<=13;i++){
        for(int j=0;j<=19;j++){
            System.out.print(background[i][j]);
        }
    }
}

Answer 2

Why do we need multiple for loops here. If you want to read characters from a file you could use buffered reader and the this matrix could be created in one line of code like while((bufferedReader.read(background[i]) != -1) && (++i < 14)){ } . Also you are using a while loop to read one char and then an unconditional break statment inside is not a good practice (in my opinion). Try

public static void main(String[] args) throws IOException {

    char background[][] = new char[14][20];
    try {
        FileReader fileReader = new FileReader("background.txt");
        BufferedReader bufferedReader = new BufferedReader(fileReader);

        int i=0;
        while((bufferedReader.read(background[i]) != -1) && (++i < 14)){ } // This like created your 2D array

        bufferedReader.close();
        fileReader.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    }
    for (int i = 0; i <= 13; i++) {
        for (int j = 0; j <= 19; j++) {
            System.out.print(background[i][j]);
        }
    }
}