定义一个复数类，并实现以下复数类的方法：构造方法、得到实、虚部、设置实部、虚部、复数的加法，减法，乘法，最后，创建对象进行运算。用java编写

为了定义一个复数类并实现所需的方法，我们可以使用Java的类定义和成员变量来存储实部和虚部。以下是一个简单的示例：

public class ComplexNumber {
    private double real; // 实部
    private double imaginary; // 虚部

    // 构造方法，初始化复数
    public ComplexNumber(double real, double imaginary) {
        this.real = real;
        this.imaginary = imaginary;
    }

    // 获取实部
    public double getReal() {
        return real;
    }

    // 获取虚部
    public double getImaginary() {
        return imaginary;
    }

    // 设置实部和虚部
    public void setReal(double real) {
        this.real = real;
    }
    public void setImaginary(double imaginary) {
        this.imaginary = imaginary;
    }

    // 复数加法
    public ComplexNumber add(ComplexNumber other) {
        double realPart = this.real + other.getReal();
        double imaginaryPart = this.imaginary + other.getImaginary();
        return new ComplexNumber(realPart, imaginaryPart);
    }

    // 复数减法
    public ComplexNumber subtract(ComplexNumber other) {
        double realPart = this.real - other.getReal();
        double imaginaryPart = this.imaginary - other.getImaginary();
        return new ComplexNumber(realPart, imaginaryPart);
    }

    // 复数乘法
    public ComplexNumber multiply(ComplexNumber other) {
        double realPart = this.real * other.getReal() - this.imaginary * other.getImaginary();
        double imaginaryPart = this.real * other.getImaginary() + this.imaginary * other.getReal();
        return new ComplexNumber(realPart, imaginaryPart);
    }

    // 打印复数
    @Override
    public String toString() {
        if (imaginary >= 0) {
            return "(" + real + " + " + imaginary + "i)";
        } else {
            return "(" + real + " - " + (-imaginary) + "i)";
        }
    }

    public static void main(String[] args) {
        ComplexNumber c1 = new ComplexNumber(2, 3);
        ComplexNumber c2 = new ComplexNumber(-1, 4);

        System.out.println("c1: " + c1); // 输出 (2 + 3i)
        System.out.println("c2: " + c2); // 输出 (-1 + 4i)

        ComplexNumber sum = c1.add(c2);
        System.out.println("Sum: " + sum); // 输出 (1 + 7i)

        ComplexNumber diff = c1.subtract(c2);
        System.out.println("Difference: " + diff); // 输出 (3 - 1i)

        ComplexNumber product = c1.multiply(c2);
        System.out.println("Product: " + product); // 输出 (10 - 5i)
    }
}

这个例子中，我们定义了一个`ComplexNumber`类，包含了构造方法、getter和setter方法，以及复数之间的加法、减法和乘法操作。在`main`方法中，我们创建了两个复数对象，并进行了相应的运算。