Random mockRandom = mock(Random.class);
when(mockRandom.nextInt()).thenThrow(new RuntimeException("异常"));
try {
mockRandom.nextInt();
Assert.fail(); // 上面会抛出异常，所以不会走到这里
} catch (Exception ex) {
Assert.assertTrue(ex instanceof RuntimeException);
Assert.assertEquals("异常", ex.getMessage());
thenThrow 中可以指定多个异常。在调用时异常依次出现。若调用次数超过异常的数量，再次调用时抛出最后一个异常。
import org.junit.Assert;
import org.junit.Test;
import static org.mockito.Mockito.*;
import java.util.Random;
public class MockitoDemo {
@Test
public void test() {
Random mockRandom = mock(Random.class);
when(mockRandom.nextInt()).thenThrow(new RuntimeException("异常1"), new RuntimeException("异常2"));
try {
mockRandom.nextInt();
Assert.fail();
} catch (Exception ex) {
Assert.assertTrue(ex instanceof RuntimeException);
Assert.assertEquals("异常1", ex.getMessage());
try {
mockRandom.nextInt();
Assert.fail();
} catch (Exception ex) {
Assert.assertTrue(ex instanceof RuntimeException);
Assert.assertEquals("异常2", ex.getMessage());
对应返回类型是 void 的函数，thenThrow 是无效的，要使用 doThrow。
