Failed to load ApplicationContext when running Spring boot integration test

Question

I am trying to write integration test for spring boot. I want the server should be up during test so that I can connect the client from the test code. Using java 1.7. I am getting exception when running as maven test. (From console)

java.lang.IllegalStateException: Failed to load ApplicationContext
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124)
    at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:83)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:117)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83)
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:228)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:230)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:291)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:249)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:89)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:193)
    at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:236)
    at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:134)
    at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:113)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray(ReflectionUtils.java:189)
    at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:165)
    at org.apache.maven.surefire.booter.ProviderFactory.invokeProvider(ProviderFactory.java:85)
    at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:103)
    at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:74)
Caused by org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerAdapter' defined in class path resource [org/springframework/boot/autoconfigure/web/WebMvcAutoConfiguration$EnableWebMvcConfiguration.class]: Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: java/util/Optional
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1578)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:772)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:838)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:537)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752)
    at org.springframework.boot.SpringApplication.doRun(SpringApplication.java:347)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:295)
    at org.springframework.boot.test.SpringApplicationContextLoader.loadContext(SpringApplicationContextLoader.java:98)
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:98)
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:116)
    ... 31 more
Caused by java.lang.NoClassDefFoundError: java/util/Optional
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.getDefaultArgumentResolvers(RequestMappingHandlerAdapter.java:590)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.afterPropertiesSet(RequestMappingHandlerAdapter.java:514)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574)
    ... 47 more
Caused by java.lang.ClassNotFoundException: java.util.Optional
    at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
    ... 51 more

My Pom.xml

<spring.release>1.3.0.RELEASE</spring.release>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-web</artifactId>
        <version>${spring.release}</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.11</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <version>${spring.release}</version>
        <scope>test</scope>
    </dependency>

Integration Test Code

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(AppConfig.class)
@WebAppConfiguration
@IntegrationTest("server.port:8090")
public class WebSocketTest {
    @Test
    public void testWebSocket() throws InterruptedException {}
}

Application configuration:

@Configuration
@ComponentScan(basePackages = {"com.test"})
@SpringBootApplication
class AppConfig {
}

It is not able to load the application context

Answer 1

As you can see in your stacktrace, there is no java.util.Optional class. This class was introduced in Java 8, but you use Java 7. So you have to remove usage of java.util.Optional or update your Java version.

Answer 2

I'm also using Java 7 and I encountered this error. To my knowledge, none of my code attempted to utilize java.util.Optional. From what I understand, it was caused by having surefire's forkMode set to once for some reason. No idea why. So I split up my tests in my pom.xml:

    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-surefire-plugin</artifactId>
      <inherited>true</inherited>
      <configuration>
        <skip>true</skip>
      </configuration>
      <executions>
        <execution>
          <id>everything-but-problematic-test</id>
          <phase>test</test>
          <goals>
            <goal>test</goal>
          </goals>
          <configuration>
            <skip>false</skip>
            <forkMode>once</forkMode>
            <excludes>
              <exclude>**/*problematic-test.java</exclude>
            </excludes>
          </configuration>
        </execution>
        <execution>
          <id>problematic-test</id>
          <phase>test</test>
          <goals>
            <goal>test</goal>
          </goals>
          <configuration>
            <skip>false</skip>
            <forkMode>none</forkMode>
            <includes>
              <include>**/*problematic-test.java</include>
            </includes>
          </configuration>
        </execution>
      </executions>
    </plugin>

I run the tests separately because in my case, simply setting forkMode to none broke other tests. That being said, you could try setting forkmode to none for everything before tearing apart your pom.xml