如何用Java模拟XN*2图灵机

import java.util.*; 

public class TuringMachine {
 
    private int internalState; // 图灵机的内态
    private String binCode; // 二进制编码
    Function f = new Function(); // 需要用到的方法
    List<String> binCodeList = new ArrayList<>(); // 用来存放二进制编码
 
    static int r = 0; // 当r为1时机器向右移动一格
    static int s = 0; // 当s为1时机器停止运行
 
    TuringMachine() {
        internalState = 0;
        binCode = "0";
    }
 
    public int getInternalState() {
        return internalState;
    }
 
    public void setInternalState(int internalState) {
        this.internalState = internalState;
    }
 
    public String getBinCode() {
        return binCode;
    }
 
    public void setBinCode(String binCode) {
        this.binCode = binCode;
    }
 
    
    public void runProcess(String binCode) {
        binCodeList = f.toArrayList(binCode); // 将二进制码binCode转换为ArrayList类型存放在binCodeList中
        // for循环对binCodeList进行遍历，根据当前内态的值判断该执行哪条指令
        for (int i = 0; i < binCodeList.size(); i++) {
            r = 1;
            // 当s==1时机器停止，跳出循环
            if (s == 1) {
                break;
            }
            switch (getInternalState()) {
                // 内态为0时执行指令1
                case 0:
                    instruction_1(binCodeList.get(i), i, binCodeList);
                    break;
                // 内态为1时执行指令2
                case 1:
                    instruction_2(binCodeList.get(i), i, binCodeList);
                    break;
                // 内态为10时执行指令3
                case 10:
                    instruction_3(binCodeList.get(i), i, binCodeList);
                    break;
                // 内态为11时执行指令4
                case 11:
                    instruction_4(binCodeList.get(i), i, binCodeList);
                    break;
                default:
                    break;
            }
        }
        System.out.println("XN*2图灵机计算的最终结果为：");
        f.toDecNum(f.toString(binCodeList)); // 将binCodeList转换为String类型的二进制编码binCode，再转换为int类型的十进制数decNum
    } 
    
    private void instruction_1(String input, int i, List<String> binCodeList) {
        System.out.println("当前的内态为：" + getInternalState() + "，输入为：" + input);
        if (input.equals("0")) {
            System.out.println("执行此条指令后的内态为：" + getInternalState() + "，输入为：" + binCodeList.get(i) + "，右移");
            System.out.println("此步骤的结果为：");
            System.out.println(f.toString(binCodeList));
        }
        if (input.equals("1")) {
            setInternalState(1);
            binCodeList.set(i, "0");
            System.out.println("执行此条指令后的内态为：" + getInternalState() + "，输入为：" + binCodeList.get(i) + "，右移");
            System.out.println("此步骤的结果为：");
            System.out.println(f.toString(binCodeList));
        }
        System.out.println();
    }
 
    private void instruction_2(String input, int i, List<String> binCodeList) {
        System.out.println("当前的内态为：" + getInternalState() + "，输入为：" + input);
        if (input.equals("0")) {
            setInternalState(0);
            binCodeList.set(i, "1");
            System.out.println("执行此条指令后的内态为：" + getInternalState() + "，输入为：" + binCodeList.get(i) + "，右移");
            System.out.println("此步骤的结果为：");
            System.out.println(f.toString(binCodeList));
        }
        if (input.equals("1")) {
            setInternalState(10);
            binCodeList.set(i, "0");
            System.out.println("执行此条指令后的内态为：" + getInternalState() + "，输入为：" + binCodeList.get(i) + "，右移");
            System.out.println("此步骤的结果为：");
            System.out.println(f.toString(binCodeList));
        }
        System.out.println();
    }
 
    private void instruction_3(String input, int i, List<String> binCodeList) {
        System.out.println("当前的内态为：" + getInternalState() + "，输入为：" + input);
        if (input.equals("0")) {
            setInternalState(11);
            binCodeList.set(i, "1");
            System.out.println("执行此条指令后的内态为：" + getInternalState() + "，输入为：" + binCodeList.get(i) + "，右移");
            System.out.println("此步骤的结果为：");
            System.out.println(f.toString(binCodeList));
        }
        System.out.println();
    }
 
    private void instruction_4(String input, int i, List<String> binCodeList) {
        System.out.println("当前的内态为：" + getInternalState() + "，输入为：" + input);
        if (input.equals("0")) {
            setInternalState(0);
            binCodeList.set(i, "1");
            System.out.println("执行此条指令后的内态为：" + getInternalState() + "，输入为：" + binCodeList.get(i) + "，STOP");
            System.out.println("此步骤的结果为：");
            System.out.println(f.toString(binCodeList));
        }
        s = 1;
        System.out.println();
    }
 
    public static void main(String[] args) {
        TuringMachine tm = new TuringMachine(); // 创建TuringMachine的实例tm
        System.out.println("请输入一个十进制数：");
        Scanner scanner = new Scanner(System.in);
        try {
            int decNum = scanner.nextInt();
            tm.setBinCode(tm.f.toBinCode(decNum)); // 将十进制数转换为二进制编码并赋值给binCode
            System.out.println();
            tm.runProcess(tm.getBinCode()); // 运行图灵机
        } catch (InputMismatchException ex) {
            System.out.println("输入有误！");
        }
    } 
}
 

class Function {
 
    
    public String toBinCode(int decNum) {
        String binCode = "";
        String binNum = Integer.toBinaryString(decNum); // 十进制数转换为二进制数
        binNum += ","; // 用,标识此二进制数到此已完整，后面的0都忽略不计
        System.out.println("这个数的二进制表示为：" + binNum);
        // 利用for循环对二进制数binNum中的字符进行遍历，根据其中的每个字符得出二进制编码binCode
        for (int i = 0; i < binNum.length(); i++) {
            // 0 -> 0
            if (binNum.charAt(i) == '0') {
                binCode += "0";
                // 1 -> 10
            } else if (binNum.charAt(i) == '1') {
                binCode += "10";
                // , -> 110
            } else if (binNum.charAt(i) == ',') {
                binCode += "110";
            }
        }
        binCode = "0" + binCode + "00";
        System.out.println("这个数的二进制编码为：" + binCode);
        return binCode;
    }
 
    
    public int toDecNum(String binCode) {
        int decNum = 0;
        String binNum = "";
        // 先利用for循环对ArrayList类型的binCode进行遍历，根据其中的每个元素得出二进制编码binCode
        for (int i = 0; i < binCode.length(); i++) {
            // 0 -> 0
            if (binCode.charAt(i) == '0') {
                binNum += "0";
            } else if (binCode.charAt(i) == '1') {
                // 10 -> 1
                if (binCode.charAt(i + 1) == '0') {
                    binNum += "1";
                    i++;
                    // 110 -> ,
                } else if (binCode.charAt(i + 1) == '1') {
                    binNum += ",";
                    break;
                }
            }
        }
        System.out.println("二进制表示：" + binNum);
        decNum = Integer.parseInt(binNum.substring(0, binNum.length() - 1), 2); // 将二进制编码binCode转化为十进制数
        System.out.println("十进制表示：" + decNum);
        return decNum;
    }
 
    
    public List<String> toArrayList(String binCode) {
        binCode = binCode.replaceAll("", " ").trim(); // 将binCode中的每个字符用空格分隔开，并去掉首尾的空格
        // 根据分隔符空格分隔出binCode中的每个字符存放到binCodeList中
        List<String> binCodeList = new ArrayList<>(Arrays.asList(binCode.split(" ")));
        return binCodeList;
    }
 
    
    public String toString(List<String> binCodeList) {
        String binCode = String.join("", binCodeList);
        return binCode;
    } 
}