Java 为复数类的除法加上自定义异常处理。

在Java中，我们可以创建一个名为`ComplexNumber`的复数类，用于表示复数，并添加一个`divide`方法来执行除法运算。为了处理可能出现的特殊情况，比如除数为零的情况，我们需要自定义一个异常——例如`DivideByZeroException`。下面是一个简单的示例：

import java.util.Objects;

class ComplexNumber {
    private double real;
    private double imaginary;

    public ComplexNumber(double real, double imaginary) {
        this.real = real;
        this.imaginary = imaginary;
    }

    // 获取和设置复数元素
    public double getReal() { return real; }
    public double getImaginary() { return imaginary; }
    
    // 自定义除法方法，带异常处理
    public ComplexNumber divide(ComplexNumber divisor) throws DivideByZeroException {
        if (Objects.equals(divisor.getReal(), 0) && Objects.equals(divisor.getImaginary(), 0)) {
            throw new DivideByZeroException("试图除以零");
        }
        
        double denominator = divisor.getReal() * divisor.getReal() + divisor.getImaginary() * divisor.getImaginary();
        double quotientReal = (this.real * divisor.getReal() + this.imaginary * divisor.getImaginary()) / denominator;
        double quotientImaginary = (this.imaginary * divisor.getReal() - this.real * divisor.getImaginary()) / denominator;
        
        return new ComplexNumber(quotientReal, quotientImaginary);
    }
}

class DivideByZeroException extends RuntimeException {
    public DivideByZeroException(String message) {
        super(message);
    }
}

// 使用示例
public static void main(String[] args) {
    try {
        ComplexNumber c1 = new ComplexNumber(3, 4);
        ComplexNumber c2 = new ComplexNumber(1, 1);
        ComplexNumber result = c1.divide(c2);
        System.out.println(result); // 打印结果
    } catch (DivideByZeroException e) {
        System.out.println(e.getMessage());
    }