Need this done in Java please. JUnit 4

Need a class that tests all constructors and methods for the following class. All different cases need to be tested. setUp method should also be included in the class. should be called before each test method is executed.

import java.util.*;

class ComplexNum {

private double real; private double imaginary;

public ComplexNum() { setReal(0); setImaginary(0); } public ComplexNum(double real) { setReal(real); setImaginary(0); } public ComplexNum(double real, double imaginary) { setReal(real); setImaginary(imaginary); } public double getReal() { return real; } public double getImaginary() { return imaginary; } public void setReal(double real) { this.real = real;

} public void setImaginary(double imaginary) { this.imaginary = imaginary; }

public ComplexNum add(ComplexNum obj) { double reals = this.real + obj.real; double imaginaries = this.imaginary + obj.imaginary; return new ComplexNum(reals, imaginaries);

}

public ComplexNum sub(ComplexNum obj) { double reals = this.real - obj.real; double imaginaries = this.imaginary - obj.imaginary;

return new ComplexNum(reals, imaginaries); }

public ComplexNum mul(ComplexNum obj){ double reals = (this.real * obj.real) - (this.imaginary * obj.imaginary); double imaginaries = (this.real * obj.imaginary) + (this.imaginary * obj.real);

return new ComplexNum(reals, imaginaries); } public ComplexNum neg() { return new ComplexNum(-this.real, -this.imaginary); } public String toString() { StringBuilder sb = new StringBuilder(); if (this.real != 0) { sb.append(this.real); if (this.imaginary > 0) { sb.append("+"); } } if (this.imaginary != 0) { sb.append(this.imaginary).append("i"); } if (sb.length() == 0) { sb.append("0"); } return sb.toString(); }

@Override public boolean equals(Object obj) { if (!(obj instanceof ComplexNum)) { return false; } ComplexNum other = (ComplexNum) obj; return this.real == other.real && this.imaginary == other.imaginary; }

}