您如何断言在JUnit 4测试中引发了某种异常？推荐｜ Java Debug 笔记

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提问：您如何断言在JUnit 4测试中引发了某种异常？

如何惯用JUnit4来测试某些代码引发异常？

虽然我当然可以做这样的事情：

@Test
public void testFooThrowsIndexOutOfBoundsException() {
  boolean thrown = false;

  try {
    foo.doStuff();
  } catch (IndexOutOfBoundsException e) {
    thrown = true;
  }

  assertTrue(thrown);
}
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我记得在这种情况下，有一个批注或一个Assert.xyz或一些不那么杂乱无章的东西，更像是JUnit的精髓。

高分回答：

$\color{purple}很多的知识点，真的需要写出来才会掌握!!!{~}$

编辑：现在已经发布了JUnit 5和JUnit 4.13，最好的选择是使用Assertions.assertThrows()（对于JUnit 5）和Assert.assertThrows()（对于JUnit 4.13+）。请参阅我的其他答案以获取详细信息。

如果您尚未迁移到JUnit 5，但可以使用JUnit 4.7，则可以使用ExpectedExceptionRule：

public class FooTest {
  @Rule
  public final ExpectedException exception = ExpectedException.none();

  @Test
  public void doStuffThrowsIndexOutOfBoundsException() {
    Foo foo = new Foo();

    exception.expect(IndexOutOfBoundsException.class);
    foo.doStuff();
  }
}
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这要好得多，@Test(expected=IndexOutOfBoundsException.class)因为如果IndexOutOfBoundsException之前抛出测试，测试将失败foo.doStuff()

文章翻译自 am2dgbqfb6mk75jcyanzabc67y-ac4c6men2g7xr2a-stackoverflow-com.translate.goog/questions/1…

作者建议：我们的接口都需要做单元测试，这里给出几个简单事例

redis

@RunWith(SpringRunner.class)
@EnableAutoConfiguration
@SpringBootTest(classes = JedisClusterConfiguration.class)
public class JedisClusterConfigurationTest {

    @Autowired
    private JedisCluster jedis;

    @Test
    public void test() {
        System.out.println(jedis.lpush("l1", "123"));
        System.out.println(jedis.lpush("l1", "456"));
        System.out.println(jedis.lrange("l1", 0, -1));
        System.out.println(jedis.hset("h1", "k1", "v1"));
        System.out.println(jedis.hset("h1", "k2", "v2"));
        System.out.println(jedis.hset("h1", "k3", "v3"));
        System.out.println(jedis.hset("h1", "k4", "v4"));
        System.out.println(jedis.hget("h1", "k3"));
        System.out.println(jedis.hgetAll("h1"));
        System.out.println(jedis.set("hello", "world"));
        System.out.println(jedis.get("hello"));
    }
}
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文件

@RunWith(SpringRunner.class)
@EnableAutoConfiguration
@SpringBootTest(classes = FileClientConfiguration.class)
public class FileClientServiceTest {
    @Autowired
    private FileClientService fileClientService;

    @Test
    public void upload() throws IOException {
        String filePath = "D:\\Pictures\\1ba5ee77-775b-469e-88ae-b8ad23b501fc.jpg";
        String originalFilename = "img.mmexport123123123213";
        MockMultipartFile file = new MockMultipartFile("file", originalFilename, "multipart/form-data", new FileInputStream(filePath));
        String newFileName = fileClientService.upload(file);
        System.out.println(newFileName);
    }
}
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限流

import com.sinoiov.spring.boot.autoconfigure.ratelimit.config.RateLimitProperties;
import com.sinoiov.spring.boot.autoconfigure.ratelimit.config.RateLimitType;
import com.sinoiov.spring.boot.autoconfigure.ratelimit.ratelimit.impl.MaxRateLimiter;
import org.junit.Before;
import org.junit.Test;
import org.mockito.MockitoAnnotations;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class MaxRateLimitTest {

    private static final Logger logger = LoggerFactory.getLogger(MaxRateLimitTest.class);

    @Before
    public void setUp() {
        MockitoAnnotations.initMocks(this);
    }

    @Test
    public void test() throws InterruptedException {
        RateLimitProperties.Policy policy = new RateLimitProperties.Policy();
        policy.setType(RateLimitType.MAX_LIMIT);
        policy.setLimit(3L);
        policy.setRefreshInterval(3L);
        policy.setUrl("/abc");
        MaxRateLimiter maxRateLimiter = new MaxRateLimiter(policy);
        for (int i = 0; i < 13; i++) {
            Thread.sleep(1 * 1000);
            logger.info("{}", maxRateLimiter.tryAcquire());
        }
        Thread.sleep(4 * 1000);

        logger.info("{}", maxRateLimiter.tryAcquire());

        Thread.sleep(9 * 1000);

        logger.info("{}", maxRateLimiter.tryAcquire());
        logger.info("{}", maxRateLimiter.tryAcquire());
        logger.info("{}", maxRateLimiter.tryAcquire());
        logger.info("{}", maxRateLimiter.tryAcquire());

        logger.info("开始退还令牌");
        maxRateLimiter.giveBack();
        maxRateLimiter.giveBack();
        maxRateLimiter.giveBack();
        maxRateLimiter.giveBack();
        maxRateLimiter.giveBack();
        for (int i = 0; i < 5; i++) {
            logger.info("{}", maxRateLimiter.tryAcquire());
        }
        logger.info("{}", "Done!");
    }
}

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http请求

@Test
	public void findBanks() throws Exception {
		String url = "https://xxx";
		Map<String, Object> para = new HashMap<String, Object>();
		// para.put("merchant_id", "100000001303441");
		para.put("bank_name", "xxx");
		para.put("charset", "UTF-8");
		para.put("province_name", "xx");
		para.put("city_name", "xx");
		para.put("sign_type", "RSA");
//		para.put("Sign", null);
		String result = ReapalSendUtils.send(para, url); // 调用HTTPClient
		logger.info(result);
		result = Decipher.decryptData(result);
		logger.info(result);
	}
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真心感谢帅逼靓女们能看到这里，如果这个文章写得还不错，觉得有点东西的话

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