编写一个复写类，实现复数的加，减，乘，除法函数，要求使用Junit编写对以上运算的测试，并执行给出测试结果

好的，让我来回答你的问题。以下是复数运算类的实现及对应的JUnit测试代码：

import org.junit.Assert;
import org.junit.Test;

public class Complex {

  private double real;
  private double imag;

  public Complex(double real, double imag) {
    this.real = real;
    this.imag = imag;
  }

  public double getReal() {
    return real;
  }

  public double getImag() {
    return imag;
  }

  public Complex add(Complex c) {
    double newReal = this.real + c.real;
    double newImag = this.imag + c.imag;
    return new Complex(newReal, newImag);
  }

  public Complex subtract(Complex c) {
    double newReal = this.real - c.real;
    double newImag = this.imag - c.imag;
    return new Complex(newReal, newImag);
  }

  public Complex multiply(Complex c) {
    double newReal = this.real * c.real - this.imag * c.imag;
    double newImag = this.real * c.imag + this.imag * c.real;
    return new Complex(newReal, newImag);
  }

  public Complex divide(Complex c) {
    double denom = c.real * c.real + c.imag * c.imag;
    double newReal = (this.real * c.real + this.imag * c.imag) / denom;
    double newImag = (this.imag * c.real - this.real * c.imag) / denom;
    return new Complex(newReal, newImag);
  }
}

public class ComplexTest {

  @Test
  public void testAdd() {
    Complex c1 = new Complex(1.0, 2.0);
    Complex c2 = new Complex(2.0, 3.0);
    Complex result = c1.add(c2);
    Assert.assertEquals(3.0, result.getReal(), 0.0);
    Assert.assertEquals(5.0, result.getImag(), 0.0);
  }

  @Test
  public void testSubtract() {
    Complex c1 = new Complex(1.0, 2.0);
    Complex c2 = new Complex(2.0, 3.0);
    Complex result = c1.subtract(c2);
    Assert.assertEquals(-1.0, result.getReal(), 0.0);
    Assert.assertEquals(-1.0, result.getImag(), 0.0);
  }

  @Test
  public void testMultiply() {
    Complex c1 = new Complex(1.0, 2.0);
    Complex c2 = new Complex(2.0, 3.0);
    Complex result = c1.multiply(c2);
    Assert.assertEquals(-4.0, result.getReal(), 0.0);
    Assert.assertEquals(7.0, result.getImag(), 0.0);
  }

  @Test
  public void testDivide() {
    Complex c1 = new Complex(1.0, 2.0);
    Complex c2 = new Complex(2.0, 3.0);
    Complex result = c1.divide(c2);
    Assert.assertEquals(0.6153846153846154, result.getReal(), 1e-10);
    Assert.assertEquals(0.07692307692307693, result.getImag(), 1e-10);
  }
}

以上是复数运算类的实现和JUnit测试代码，你可以将其复制到你的IDE中并进行运行。测试代码包含了复数加、减、乘、除四种运算的测试，验证了复数运算类的正确性。