将马在 x 轴和 y 轴上旋转 10 度角 Java

Question

我正在尝试在 Java 中编写一个程序，其中我在文本文件中编写了一些命令，根据这些命令，马将朝相同的方向移动或将其角度改变 10 度.马的起始位置是 (0,0) 并且面向东方目的地表示为以 (500,0) 坐标为中心的正方形。正方形在(500,0)坐标的北、南、东、西各延伸30米：

here is the position of horse

这是 command.txt 文件：

Go
Hah
Go
Gaff
Go
Gaff
Go
Go
Whoa

命令含义：

Go 朝您面对的方向前进 50 米。

Hah 向左转 10 度，但不要向前移动。

Gaff 向右转 10 度，但不要向前移动。

Whoa 停止。

代码如下：

    import java.io.File;
    import java.io.FileNotFoundException;
    import java.util.Scanner;

    public class HorseRiding {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        System.out.println("Enter the path of the file");

        Scanner sc = new Scanner(System.in);
        String filename = sc.nextLine();
        horse(filename);        
    }


    public static void horse(String filename) {


        File inputFile = new File(filename);

        Scanner readFile = null;

        try {
             readFile = new Scanner(inputFile);

        } catch (FileNotFoundException e) {

            System.out.println("Error! File not found!");
        }



    double x=0, y=0, angle=0, distance=50, x2=0, y2=0;


    System.out.println("The horse starts at: (" + x + "," + y + ")");

    while(readFile.hasNextLine()){

        String line = readFile.nextLine();

            while(line.equals("Go"))
            {
                x += distance + x2;
                y += y2;
                System.out.println("Command: "+line+", New position: ("+x+", "+y+")");
                line = readFile.nextLine();
            }

            while(line.equals("Hah"))
            {
                angle -= 10;
                x2 = distance * Math.cos(angle);
                y2 = distance * Math.sin(angle);
                System.out.println("Command: "+line+", New position: ("+x+", "+y+")");
                line = readFile.nextLine();

            }

            while(line.equals("Gaff"))
            {
                angle+=10;
                x2 = distance * Math.cos(angle);
                y2 = distance * Math.sin(angle);
                System.out.println("Command: "+line+", New position: ("+x+", "+y+")");
                line = readFile.nextLine();
            }

            while(line.equals("Whoa"))
            {
                System.out.println("Final Position of Horse: ("+x+", "+y+")");

                if((x<530.00 && x>470) && (y>-30.00 && y<30.00)) {
                    System.out.println("SUCCESS");
                    break;
                }
                else {
                    System.out.println("FAILURE");
                    break;
                }
            }

            readFile.close();

            }
        }

    }

我遇到异常错误：

    Exception in thread "main" java.lang.IllegalStateException: Scanner closed
    at java.base/java.util.Scanner.ensureOpen(Scanner.java:1150)
    at java.base/java.util.Scanner.findWithinHorizon(Scanner.java:1781)
    at java.base/java.util.Scanner.hasNextLine(Scanner.java:1610)
    at HorseRiding.horse(HorseRiding.java:40)
    at HorseRiding.main(HorseRiding.java:14)

而且，它运行了两次，直到第二个命令Hah，然后抛出上述异常。

Answer 1

请查看以下代码段，这里解决了一些其他问题：

处理每个命令的简化逻辑。
修复了 x2、y2 的计算，因为 Math.cos、Math.sin 接受以弧度为单位的角度，而不是度数。
添加了 angle 的印刷品。
添加了成功点和范围的参数。

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

public class HorseRiding {

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

        System.out.println("Enter the path of the file");

        Scanner sc = new Scanner(System.in);
        String filename = sc.nextLine();
        horse(filename); 
        //horse("horse.txt");
    }

private static void horse(String filename) throws FileNotFoundException {
        File inputFile = new File(filename);
        Scanner readFile = new Scanner(inputFile);

        final double distance = 50, successX = 500, successY = 0, range = 30;
        double x = 0, y = 0, angle = 0, x2 = distance, y2 = 0;

        System.out.println("The horse starts at: (" + x + ", " + y + ")");
        while (readFile.hasNext()) {
            String command = readFile.next();
            if ("Whoa".equals(command)) {
                break;
            }
            if ("Go".equals(command)) {
                x += x2;
                y += y2;
            } else if ("Hah".equals(command) || "Gaff".equals(command)) {
                angle += "Hah".equals(command) ? 10 : -10;
                x2 = distance * Math.cos(Math.toRadians(angle));
                y2 = distance * Math.sin(Math.toRadians(angle));
            }
            //System.out.println("Command: " + command + ", New position: (" + x + ", " + y + "), angle: " + angle);
            System.out.printf("Command: %-4s\tNew position: (%6.2f, %6.2f)\tangle: % 3.0f%n", 
                    command, x, y, angle);
        }
        if (x >= successX - range && x <= successX + range && 
            y >= successY - range && y <= successY + range) {
            System.out.println("SUCCESS");
        } else {
            System.out.println("FAILURE");
        }
        readFile.close();
    }
}

给定样本文件的结果输出是：

Enter the path of the file
horse.txt
The horse starts at: (0.0, 0.0)
Command: Go     New position: ( 50.00,   0.00)  angle:   0
Command: Hah    New position: ( 50.00,   0.00)  angle:  10
Command: Go     New position: ( 99.24,   8.68)  angle:  10
Command: Gaff   New position: ( 99.24,   8.68)  angle:   0
Command: Go     New position: (149.24,   8.68)  angle:   0
Command: Gaff   New position: (149.24,   8.68)  angle: -10
Command: Go     New position: (198.48,   0.00)  angle: -10
Command: Go     New position: (247.72,  -8.68)  angle: -10
FAILURE

将马在 x 轴和 y 轴上旋转 10 度角 Java

Rotate a horse by 10 degree angle in x axis as well as y axis in Java

java

exception

angle

coordinates