Maven Surefire并发修改异常

Question

当 Maven 构建我的项目并运行进行单元测试时，有时会抛出并发修改异常（大约 5 次中有 1 次会失败，其他时候会成功构建）。但是当我运行本地测试作为单元测试时，它们都无一例外地通过了。

在我的 pom.xml 文件中，我将 Surefire 插件配置为：

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-surefire-plugin</artifactId>
    <version>2.19.1</version>
    <configuration>
        <forkCount>1C</forkCount>
        <reuseForks>true</reuseForks>
    </configuration>
    <dependencies>
        <dependency>
              <groupId>org.apache.maven.surefire</groupId>
              <artifactId>surefire-junit47</artifactId>
              <version>2.19.1</version>
        </dependency>
    </dependencies>
</plugin>

但是我得到的堆栈跟踪没有提到导致并发修改异常的原因。

我注意到构建时所有测试都通过了，但出于某种原因，Maven 重印了已经通过但现在有测试异常 ConcurrentModification 的测试结果。

我不确定是什么原因导致测试结果被重印，或者是否由于某种原因在测试第一个运行的同时重新运行还没有完成，因为它是并行构建？（不确定为什么会重新运行测试）

堆栈跟踪

[Test executing]

13:48:24.869 [00001-main] DEBUG o.s.t.c.s.DirtiesContextTestExecutionListener - After test method: context [DefaultTestContext@375046d6 testClass = Tests, testInstance = com.application.Tests@179181c, testMethod = failingTest@Tests, testException = [null], mergedContextConfiguration = [WebMergedContextConfiguration@3f7b4a61 testClass = Tests, locations = '{}', classes = '{class com.Application}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{}', resourceBasePath = 'src/main/app', contextLoader = 'org.springframework.test.context.web.WebDelegatingSmartContextLoader', parent = [null]]], class dirties context [false], class mode [null], method dirties context [false].
13:48:24.869 [00001-main] DEBUG o.s.t.c.w.ServletTestExecutionListener - Resetting RequestContextHolder for test context [DefaultTestContext@375046d6 testClass = Tests, testInstance = com.application.Tests@179181c, testMethod = failingTest@Tests, testException = [null], mergedContextConfiguration = [WebMergedContextConfiguration@3f7b4a61 testClass = Test, locations = '{}', classes = '{class com.Application}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{}', resourceBasePath = 'src/main/app', contextLoader = 'org.springframework.test.context.web.WebDelegatingSmartContextLoader', parent = [null]]].

[Some other tests executing]

13:48:28.632 [00001-main] DEBUG o.s.t.c.s.DirtiesContextTestExecutionListener - After test method: context [DefaultTestContext@54fde1bc testClass = Tests, testInstance = com.application.Tests@57ffa818, testMethod = failingTest@Tests, testException = java.util.ConcurrentModificationException, mergedContextConfiguration = [WebMergedContextConfiguration@5247834f testClass = Tests, locations = '{}', classes = '{class com.Application}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{}', resourceBasePath = 'src/main/app', contextLoader = 'org.springframework.test.context.web.WebDelegatingSmartContextLoader', parent = [null]]], class dirties context [false], class mode [null], method dirties context [false].
13:48:28.632 [00001-main] DEBUG o.s.t.c.w.ServletTestExecutionListener - Resetting RequestContextHolder for test context [DefaultTestContext@54fde1bc testClass = Tests, testInstance = com.application.Tests@57ffa818, testMethod = failingTest@Tests, testException = java.util.ConcurrentModificationException, mergedContextConfiguration = [WebMergedContextConfiguration@5247834f testClass = Tests, locations = '{}', classes = '{class com.Application}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{}', resourceBasePath = 'src/main/app', contextLoader = 'org.springframework.test.context.web.WebDelegatingSmartContextLoader', parent = [null]]].
failingTest(com.application.Tests)  Time elapsed: 0 sec  <<< ERROR!
java.util.ConcurrentModificationException

[Some other tests executing]

Results :

Tests in error: 
  Tests.failingTest» ConcurrentModification

我不确定是什么导致并发修改异常或如何避免此问题的发生，因为它有时会发生，但失败的是同一个测试，而不是我测试套件中的其他测试。

Answer 1

我发现问题的发生是因为一个我没有模拟的方法正在创建和运行一个线程（即使线程没有修改任何资源） - 所以我模拟了它问题似乎已解决。

Answer 2

我遇到了同样的问题，但这与 Java 8 中对 Collections.sort() 所做的更改有关。.

Maven Surefire并发修改异常

Maven Surefire Concurrent Modification Exception

maven

maven-surefire-plugin

concurrentmodification