开放原子开发者工作坊

public class Colculter {
        public double sum(double a,double b){
            return a+b;
        }
        public double substract(double a,double b){
            return a-b;
        }
        public double divide(double a,double b){
            return a/b;
        }
        public double aulitply(double a,double b){
            return a*b;
        }
}

import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import static org.junit.Assert.*;

public class colculterTest {
    private Colculter mColculter;

    @Before
    public void setUp() throws Exception {
        mColculter = new Colculter();

    }

    @After
    public void tearDown() throws Exception {

    }

    @Test
    public void sum() throws Exception {
        assertEquals(8d, mColculter.sum(3d, 5d), 0);

    }

    @Test
    public void substract() throws Exception {
        assertEquals(1d, mColculter.substract(5d, 4d), 0);

    }

    @Test
    public void divide() throws Exception {
        assertEquals(4d, mColculter.divide(20d, 5d), 0);

    }

    @Test
    public void aulitply() throws Exception {
        assertEquals(20d, mColculter.divide(4d, 5d), 0);
    }
}