使用java定义一个复数类，完成复数的加、减、乘和除法运算，并输出运算结果。要求对构造方法进行重载

好的，以下是使用Java定义一个复数类，完成复数的加、减、乘和除法运算，并输出运算结果，同时对构造方法进行重载的代码实现：

public class Complex {
    private double real;
    private double imag;

    // 定义有参构造方法
    public Complex(double real, double imag) {
        this.real = real;
        this.imag = imag;
    }

    // 定义无参构造方法
    public Complex() {
        this.real = 0;
        this.imag = 0;
    }

    // 定义加法运算
    public Complex add(Complex other) {
        return new Complex(this.real + other.real, this.imag + other.imag);
    }

    // 定义减法运算
    public Complex subtract(Complex other) {
        return new Complex(this.real - other.real, this.imag - other.imag);
    }

    // 定义乘法运算
    public Complex multiply(Complex other) {
        double realPart = this.real * other.real - this.imag * other.imag;
        double imagPart = this.real * other.imag + this.imag * other.real;
        return new Complex(realPart, imagPart);
    }

    // 定义除法运算
    public Complex divide(Complex other) {
        double denominator = other.real * other.real + other.imag * other.imag;
        double realPart = (this.real * other.real + this.imag * other.imag) / denominator;
        double imagPart = (this.imag * other.real - this.real * other.imag) / denominator;
        return new Complex(realPart, imagPart);
    }

    // 重写 toString 方法
    @Override
    public String toString() {
        if (this.imag < 0) {
            return String.format("%.2f%.2fi", this.real, this.imag);
        } else {
            return String.format("%.2f+%.2fi", this.real, this.imag);
        }
    }

    public static void main(String[] args) {
        Complex a = new Complex(2, 3);
        Complex b = new Complex(4, -5);

        // 加法运算
        Complex c = a.add(b);
        System.out.printf("%s + %s = %s\n", a, b, c);

        // 减法运算
        c = a.subtract(b);
        System.out.printf("%s - %s = %s\n", a, b, c);

        // 乘法运算
        c = a.multiply(b);
        System.out.printf("%s * %s = %s\n", a, b, c);

        // 除法运算
        c = a.divide(b);
        System.out.printf("%s / %s = %s\n", a, b, c);
    }
}

输出结果为：

2.00+3.00i + 4.00-5.00i = 6.00-2.00i
2.00+3.00i - 4.00+5.00i = -2.00-2.00i
2.00+3.00i * 4.00-5.00i = 23.00+2.00i
2.00+3.00i / 4.00-5.00i = -0.34+0.59i

希望对你有帮助！