如何打破这个while（true）循环？ [英] How to break this while(true) loop?

问题描述

我想打破这个循环，在两个if语句都为true时返回坐标。但是循环永远不会结束。
如何解决？

Hi I am trying to break from this loop and return the coordinates when both if statements are true. However the loop is never ending. How can I fix it?

public static String[] positionQuery(int dim, Scanner test_in) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("Provide origin and destination coordinates.");
        System.out.println("Enter two positions between A1-H8:");
        while(true) {
            String line = scanner.nextLine();
            String[] coordinates = line.split(" ");
            if(coordinates.length == 2) {
                String origin = coordinates[0];
                String dest = coordinates[1];
                if(validCoordinate(origin, dim) && validCoordinate(dest,dim)) {
                    return coordinates;
                }
            }
            System.out.println("ERROR: Please enter valid coordinate pair separated by space.");
        }
    }

我猜我对有效的坐标有问题，因为我仅对validCoordinates正确，但是找不到我在做什么。

I guess I have a problem with validCoordinates, because I am only getting true with validCoordinates, but couldn't find what I am doing wrong.

public static boolean validCoordinate(String coordinate, int dimension) {
        boolean isValidCoordinate;
        String [] alphabet = {"A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"};
        int [] numbers = new int [dimension];
        int one = 1;
        for(int i = 0; i < dimension; i++){
            numbers[i] = one + i;
        }
        for(int i = 0; i < dimension; i++){
            if((Character.toString(coordinate.charAt(0))).contains(alphabet[i])) {
                for(int j = 0; j < dimension; j++) {
                    if ((coordinate.substring(1)).contains(Integer.toString(numbers[j]))) {
                        return true;
                    }
                }
            }
        }

        return false;
    }

推荐答案

看看是否可行。我只是做了一个Boolean标志变量来退出while循环。

See if this works. I just made a Boolean flag variable to get out the while loop. It should make the flag false once it reaches the second if.

public static String[] positionQuery(int dim, Scanner test_in) {
        Scanner scanner = new Scanner(System.in);
        System.out.println("Provide origin and destination coordinates.");
        System.out.println("Enter two positions between A1-H8:");
        Boolean flag = true;
        while(flag) {
            String line = scanner.nextLine();
            String[] coordinates = line.split(" ");
            if(coordinates.length == 2) {
                String origin = coordinates[0];
                String dest = coordinates[1];
                if(validCoordinate(origin, dim) && validCoordinate(dest,dim)) {
                    flag = false;
                    return coordinates;
                }
            }
            System.out.println("ERROR: Please enter valid coordinate pair separated by space.");
        }
    }

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