Java自定义类Octet的二进制加法实现指南

public class Octet {
    int[] x = new int[8];

    // 构造函数：接受一个8位二进制字符串
    public Octet(String s) {
        if (s.length() != 8) {
            throw new IllegalArgumentException("Input string must be 8 characters long.");
        }
        for (int i = 0; i < 8; i++) {
            char bitChar = s.charAt(i);
            if (bitChar == '1') {
                x[7 - i] = 1; // 存储时按低位到高位
            } else if (bitChar == '0') {
                x[7 - i] = 0;
            } else {
                throw new IllegalArgumentException("Input string must contain only '0' or '1'.");
            }
        }
    }

    // 将Octet对象转换为二进制字符串
    public String octetToString() {
        StringBuilder result = new StringBuilder();
        for (int i = 7; i >= 0; i--) { // 从高位到低位构建字符串
            result.append(x[i]);
        }
        return result.toString();
    }

    // 省略其他可能的方法
}

// 获取当前Octet对象的十进制值
int o1Decimal = Integer.parseInt(this.octetToString(), 2);
// 获取参数Octet对象的十进制值
int o2Decimal = Integer.parseInt(y.octetToString(), 2);

int sumDecimal = o1Decimal + o2Decimal;

String binarySum = Integer.toBinaryString(sumDecimal);

return new Octet(paddedBinarySum);

public class Octet {
    int[] x = new int[8];

    // 构造函数
    public Octet(String s) {
        if (s.length() != 8) {
            throw new IllegalArgumentException("Input string must be 8 characters long.");
        }
        for (int i = 0; i < 8; i++) {
            char bitChar = s.charAt(i);
            if (bitChar == '1') {
                x[7 - i] = 1;
            } else if (bitChar == '0') {
                x[7 - i] = 0;
            } else {
                throw new IllegalArgumentException("Input string must contain only '0' or '1'.");
            }
        }
    }

    // 将Octet对象转换为二进制字符串
    public String octetToString() {
        StringBuilder result = new StringBuilder();
        for (int i = 7; i >= 0; i--) {
            result.append(x[i]);
        }
        return result.toString();
    }

    // 实现两个Octet对象的加法
    public Octet sum(Octet y) {
        // 1. 将当前Octet和参数Octet转换为十进制整数
        int thisDecimal = Integer.parseInt(this.octetToString(), 2);
        int otherDecimal = Integer.parseInt(y.octetToString(), 2);

        // 2. 执行十进制加法
        int sumDecimal = thisDecimal + otherDecimal;

        // 3. 将十进制和转换为二进制字符串
        String binarySum = Integer.toBinaryString(sumDecimal);

        // 4. 结果处理与规范化
        // 检查是否溢出8位
        if (binarySum.length() > 8) {
            throw new ArithmeticException("Sum of octets exceeds 8-bit capacity. Result: " + binarySum);
        }

        // 补齐前导零，确保结果是8位
        StringBuilder resultBuilder = new StringBuilder(binarySum);
        while (resultBuilder.length() < 8) {
            resultBuilder.insert(0, "0"); // 在开头插入'0'
        }
        String paddedBinarySum = resultBuilder.toString();

        // 5. 构建新的Octet对象并返回
        return new Octet(paddedBinarySum);
    }

    // 示例：重写toString方法以便于打印
    @Override
    public String toString() {
        return octetToString();
    }

    public static void main(String[] args) {
        try {
            Octet oct1 = new Octet("00000001"); // 1
            Octet oct2 = new Octet("00000010"); // 2
            Octet sum1 = oct1.sum(oct2);
            System.out.println("00000001 + 00000010 = " + sum1); // 期望: 00000011 (3)

            Octet oct3 = new Octet("11111110"); // 254
            Octet oct4 = new Octet("00000001"); // 1
            Octet sum2 = oct3.sum(oct4);
            System.out.println("11111110 + 00000001 = " + sum2); // 期望: 11111111 (255)

            Octet oct5 = new Octet("11111111"); // 255
            Octet oct6 = new Octet("00000001"); // 1
            // 这将抛出异常，因为 255 + 1 = 256，超出了8位二进制表示范围
            Octet sum3 = oct5.sum(oct6);
            System.out.println("11111111 + 00000001 = " + sum3);

        } catch (IllegalArgumentException e) {
            System.err.println("Error creating Octet: " + e.getMessage());
        } catch (ArithmeticException e) {
            System.err.println("Error during Octet sum: " + e.getMessage());
        }
    }
}