org.junit.rules.ExternalResource#org.junit.ClassRule源码实例Demo

/**
 * Throw an {@link IllegalStateException} if the supplied {@code testClass}
 * does not declare a {@code public static final SpringClassRule} field
 * that is annotated with {@code @ClassRule}.
 */
private static SpringClassRule validateSpringClassRuleConfiguration(Class<?> testClass) {
	Field ruleField = null;

	for (Field field : testClass.getFields()) {
		if (ReflectionUtils.isPublicStaticFinal(field) && SpringClassRule.class.isAssignableFrom(field.getType())) {
			ruleField = field;
			break;
		}
	}

	if (ruleField == null) {
		throw new IllegalStateException(String.format(
				"Failed to find 'public static final SpringClassRule' field in test class [%s]. " +
				"Consult the javadoc for SpringClassRule for details.", testClass.getName()));
	}

	if (!ruleField.isAnnotationPresent(ClassRule.class)) {
		throw new IllegalStateException(String.format(
				"SpringClassRule field [%s] must be annotated with JUnit's @ClassRule annotation. " +
				"Consult the javadoc for SpringClassRule for details.", ruleField));
	}

	return (SpringClassRule) ReflectionUtils.getField(ruleField, null);
}
 

@Override
public void testStarted(Description description) throws Exception {
  Category[] categories = description.getTestClass().getAnnotationsByType(Category.class);

  // @Category is not repeatable -- it is only possible to get an array of length zero or one.
  if (categories.length == 1) {
    for (Class<?> c : categories[0].value()) {
      if (c == IntegrationTests.class) {
        return;
      }
    }
  }
  for (Field field : description.getTestClass().getFields()) {
    if (Modifier.isStatic(field.getModifiers()) && field.getType() == HBaseClassTestRule.class &&
      field.isAnnotationPresent(ClassRule.class)) {
      HBaseClassTestRule timeout = (HBaseClassTestRule) field.get(null);
      assertEquals(
        "The HBaseClassTestRule ClassRule in " + description.getTestClass().getName() +
          " is for " + timeout.getClazz().getName(),
        description.getTestClass(), timeout.getClazz());
      return;
    }
  }
  fail("No HBaseClassTestRule ClassRule for " + description.getTestClass().getName());
}
 

@ClassRule
public static final ConsulResource consul(){
    int port = SocketUtils.findAvailableTcpPort();
    ConsulResource consulResource = new ConsulResource(port);
    System.setProperty("spring.cloud.consul.port",String.valueOf(port));
    return consulResource;
}
 

/**
 * Validates the annotation of the rule field in the test class.
 * 
 * @param description
 */
private void validateRuleAnnotations(Description description) {

    // If the first run is a @ClassRule run, check if @Rule is annotated
    if (firstRun && !description.isTest()) {

        /*
         * Get the fields of the test class and check if there is only one
         * coverage rule and if the coverage rule field is annotation with
         * both @ClassRule and @Rule.
         */

        int numberOfCoverageRules = 0;
        for (Field field : description.getTestClass().getFields()) {

            final Class<?> fieldType = field.getType();
            if (getClass().isAssignableFrom(fieldType)) {

                ++numberOfCoverageRules;

                final boolean isClassRule = field.isAnnotationPresent(ClassRule.class);
                final boolean isRule = field.isAnnotationPresent(Rule.class);
                if (isClassRule && !isRule) {

                    throw new RuntimeException(getClass().getCanonicalName()
                            + " can only be used as a @ClassRule if it is also a @Rule!");
                }
            }
        }

        // TODO if they really want to have multiple runs, let them?
        if (numberOfCoverageRules > 1) {
            throw new RuntimeException("Only one coverage rule can be used per test class!");
        }
    }
}
 

/**
 * @return the {@code ClassRule}s that can transform the block that runs
 *         each method in the tested class.
 */
protected List<TestRule> classRules() {
    List<TestRule> result = getTestClass().getAnnotatedMethodValues(null, ClassRule.class, TestRule.class);

    result.addAll(getTestClass().getAnnotatedFieldValues(null, ClassRule.class, TestRule.class));

    return result;
}
 

private List<TestRule> getClassRules() {
  return Stream.concat(
      testClass.getAnnotatedMethodValues(null, ClassRule.class, TestRule.class).stream(),
      testClass.getAnnotatedFieldValues(null, ClassRule.class, TestRule.class).stream())
      .collect(Collectors.toList());
}
 

@ClassRule
public static TestRule rule() {
  return new ExternalResource() {
  };
}
 

/**
 * Creates a class test rule.
 *
 * @return a class test rule.
 */
@ClassRule
public static TestRule classRule() {
    return new ClassPathRule(AbstractTestSpringConfigurationFileAutoDetectingTest.class);
}
 

/**
 * Creates a class test rule.
 *
 * @return a class test rule.
 */
@ClassRule
public static TestRule classRule() {
    return new ClassPathRule(AbstractTestConfigurationFileInvalidTest.class);
}
 

/**
 * Creates a class test rule.
 *
 * @return a class test rule.
 */
@ClassRule
public static TestRule classRule() {
    return new ClassPathRule(AbstractMainSpringConfigurationFileAutoDetectingTest.class);
}
 

/**
 * Creates a class test rule.
 *
 * @return a class test rule.
 */
@ClassRule
public static TestRule classRule() {
    return new ClassPathRule(AbstractTestSpringConfigurationFileInvalidTest.class);
}
 

/**
 * Creates a class test rule.
 *
 * @return a class test rule.
 */
@ClassRule
public static TestRule classRule() {
    return new ClassPathRule(AbstractTestConfigurationFileAutoDetectingTest.class);
}
 

/**
 * Creates a class test rule.
 *
 * @return a class test rule.
 */
@ClassRule
public static TestRule classRule() {
    return new ClassPathRule(AbstractMainConfigurationFileAutoDetectingTest.class);
}
 

/**
 * Creates a class test rule.
 *
 * @return a class test rule.
 */
@ClassRule
public static TestRule classRule() {
    return new ClassPathRule(AbstractMainConfigurationFileInvalidTest.class);
}
 

/**
 * Creates a class test rule.
 *
 * @return a class test rule.
 */
@ClassRule
public static TestRule classRule() {
    return new ClassPathRule(AbstractMainSpringConfigurationFileInvalidTest.class);
}