Mockito应用
import static org.mockito.Mockito.mock;import static org.mockito.Mockito.when;import org.junit.Assert;import org.junit.Test;import org.mockito.Mockito;public class MockitoDemo {@Testpublic void mockitoTest() throws Exception {Service service = new Service();Dao dao = mock(Dao.class);// 相当于 new一个dao的模拟类service.setDao(dao);when(dao.update("1", "2")).thenReturn(2);Assert.assertEquals(2, service.update("1", "2"));// 方法的参数可以匹配任意值，Mockito.anyXXX() 和任意类 Mockito.any(clazz)when(dao.update(Mockito.anyString(), Mockito.any(String.class))).thenReturn(3);// 不能将确定值和模糊值混搭，这样会报错// when(dao.update("3", Mockito.any(String.class))).thenReturn(3);Assert.assertEquals(3, service.update("3", "4"));// 下面模拟抛异常when(dao.update("3", "4")).thenThrow(new RuntimeException());Assert.assertEquals(-1, service.update("3", "4"));// void方法抛异常Mockito.doThrow(new RuntimeException("测试")).when(dao).voidTest();try {service.voidTest();} catch (Exception e) {Assert.assertEquals("测试", e.getMessage());}// 不能模拟抛Exception类// when(dao.update("3", "4")).thenThrow(new Exception());// 同一方法不能多次模拟抛异常// when(dao.update("3", "4")).thenThrow(new NullPointerException());// Assert.assertEquals(-1, service.update("3", "4"));}}class Service {private Dao dao;public void setDao(Dao dao) {this.dao = dao;}public void voidTest() {dao.voidTest();}public int update(String a, String b) {int i = 0;try {i = dao.update(a, b);} catch (Exception e) {i = -1;}return i;}}class Dao {public void voidTest() {}public int update(String a, String b) {return 1;}}