"Address already in use: bind" exception when running Gradle JUnit tests

I'm using Spring Boot 1.2.1.RELEASE, JUnit4, and Gradle 2.1 for a RESTful service and am trying to define a properties file which includes and/or overrides values which will be used in JUnit tests only. All tests execute without an issue when invoked as a JUnit test. However, when these same tests are run during a gradle "build" or "test" task, they fail with the exception "Caused by: java.lang.IllegalStateException: Tomcat connector in failed state" with the underlying cause as "java.net.BindException: Address already in use: bind".

There are multiple test classes which require an application context in order to run.

To facilitate the alternate values via a properties file, I've included TestPropertySource()

Is there additional Gradle configuration that's needed to make this work?

ControllerTest class

@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration
@SpringApplicationConfiguration(classes = RESTAdapter.class)
@TestPropertySource(locations="classpath:application-junit.properties")
public class ControllerTest {

    @Value("${test.token}")
    private String token;

    @Autowired
    private WebApplicationContext wac;

    private MockMvc mockMvc;

    @Before
    public void setup() {
          this.mockMvc = MockMvcBuilders.webAppContextSetup(this.wac).build();
    }

    public void TestMockMvc(String[] strings) throws Exception{

        mockMvc.perform(URL_all_paramters, strings)
            .param(Constants.PARAM_TOKEN, token)
            .accept(Constants.APPLICATION_JSON_UTF8))
            .andDo(print())
            .andExpect(status().isOk())
            .andExpect(content().contentType(Constants.APPLICATION_JSON_UTF8))
            .andExpect(content().json(strings[strings.length-1]));
    }
  } 

application.properties (/src/main/resources)

logging.level.org.springframework.web=TRACE
server.port=4040
shape.file=./shape/tl_2014_34_tabblock10_county_muni.shp

application-junit.properties (/src/test/resources)

test.token=..dDKidjwel

build.gradle

buildscript {
    ext {
        springBootVersion = '1.2.1.RELEASE'
    }
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
    }
}

apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'idea'
apply plugin: 'spring-boot' 

jar {
    baseName = 'RESTfulWebServiceAdapter'
    version = '1.1.1-SNAPSHOT'
}

springBoot{
    mainClass = 'com.myapp.RESTAdapter'

}
sourceCompatibility = 1.8
targetCompatibility = 1.8

repositories {
    maven { url 'http://download.osgeo.org/webdav/geotools'} //order important for jai lib
    mavenCentral()
    maven { url 'https://repo.spring.io/libs-release'}
}


dependencies {
    compile fileTree(dir: 'lib', include: '*.jar')
    compile('org.springframework.boot:spring-boot-starter-actuator')
    compile('org.springframework.boot:spring-boot-starter-ws')  
    compile('org.geotools:gt-shapefile:9.4')
    compile('org.geotools:gt-data:9.4')
    compile('org.geotools:gt-cql:9.4')
    compile('commons-httpclient:commons-httpclient:3.1')
    compile('org.springframework.boot:spring-boot-loader')
    compile('org.springframework:spring-aspects:4.1.6.RELEASE')
    compile('org.aspectj:aspectjweaver:1.8.5')

    testCompile('org.springframework.boot:spring-boot-starter-test')
    testCompile('org.springframework.boot:spring-boot-starter-batch')
    testCompile('org.skyscreamer:jsonassert:1.2.3')
    testCompile('com.jayway.jsonpath:json-path')

}

eclipse {
    classpath {
         containers.remove('org.eclipse.jdt.launching.JRE_CONTAINER')
         containers 'org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-1.8'
    }
}

task wrapper(type: Wrapper) {
    gradleVersion = '2.1'
}

sourceSets {
    main {

        resources {
            srcDir 'config'
        }
    }
}

Stack trace:

2015-05-14 13:51:29.691 ERROR 5652 --- [    Test worker] o.a.coyote.http11.Http11NioProtocol      : Failed to start end point associated with ProtocolHandler ["http-nio-10001"]

java.net.BindException: Address already in use: bind
    at sun.nio.ch.Net.bind0(Native Method)
    at sun.nio.ch.Net.bind(Net.java:436)
    at sun.nio.ch.Net.bind(Net.java:428)
    at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:214)
    at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74)
    at org.apache.tomcat.util.net.NioEndpoint.bind(NioEndpoint.java:343)
    at org.apache.tomcat.util.net.AbstractEndpoint.start(AbstractEndpoint.java:739)
    at org.apache.coyote.AbstractProtocol.start(AbstractProtocol.java:472)
    at org.apache.coyote.http11.Http11NioProtocol.start(Http11NioProtocol.java:81)
    at org.apache.catalina.connector.Connector.startInternal(Connector.java:986)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.StandardService.addConnector(StandardService.java:237)
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer.addPreviouslyRemovedConnectors(TomcatEmbeddedServletContainer.java:186)
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer.start(TomcatEmbeddedServletContainer.java:149)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.startEmbeddedServletContainer(EmbeddedWebApplicationContext.java:288)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.finishRefresh(EmbeddedWebApplicationContext.java:141)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:483)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118)
    at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcAutoConfiguration.createChildManagementContext(EndpointWebMvcAutoConfiguration.java:219)
    at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcAutoConfiguration.afterSingletonsInstantiated(EndpointWebMvcAutoConfiguration.java:141)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:775)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:686)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.test.SpringApplicationContextLoader.loadContext(SpringApplicationContextLoader.java:100)
    at org.springframework.test.context.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:68)
    at org.springframework.test.context.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:86)
    at org.springframework.test.context.DefaultTestContext.getApplicationContext(DefaultTestContext.java:72)
    at org.springframework.test.context.web.ServletTestExecutionListener.setUpRequestContextIfNecessary(ServletTestExecutionListener.java:170)
    at org.springframework.test.context.web.ServletTestExecutionListener.prepareTestInstance(ServletTestExecutionListener.java:110)
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:212)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:200)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:259)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:261)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:219)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:83)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:68)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:163)
    at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassExecuter.runTestClass(JUnitTestClassExecuter.java:86)
    at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassExecuter.execute(JUnitTestClassExecuter.java:49)
    at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassProcessor.processTestClass(JUnitTestClassProcessor.java:69)
    at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.processTestClass(SuiteTestClassProcessor.java:48)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
    at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
    at org.gradle.messaging.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:32)
    at org.gradle.messaging.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:93)
    at com.sun.proxy.$Proxy2.processTestClass(Unknown Source)
    at org.gradle.api.internal.tasks.testing.worker.TestWorker.processTestClass(TestWorker.java:105)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
    at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
    at org.gradle.messaging.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:355)
    at org.gradle.internal.concurrent.DefaultExecutorFactory$StoppableExecutorImpl$1.run(DefaultExecutorFactory.java:64)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

2015-05-14 13:51:29.695 ERROR 5652 --- [    Test worker] o.apache.catalina.core.StandardService   : Failed to start connector [Connector[HTTP/1.1-10001]]

org.apache.catalina.LifecycleException: Failed to start component [Connector[HTTP/1.1-10001]]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:154)
    at org.apache.catalina.core.StandardService.addConnector(StandardService.java:237)
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer.addPreviouslyRemovedConnectors(TomcatEmbeddedServletContainer.java:186)
    at org.springframework.boot.context.embedded.tomcat.TomcatEmbeddedServletContainer.start(TomcatEmbeddedServletContainer.java:149)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.startEmbeddedServletContainer(EmbeddedWebApplicationContext.java:288)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.finishRefresh(EmbeddedWebApplicationContext.java:141)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:483)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118)
    at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcAutoConfiguration.createChildManagementContext(EndpointWebMvcAutoConfiguration.java:219)
    at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcAutoConfiguration.afterSingletonsInstantiated(EndpointWebMvcAutoConfiguration.java:141)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:775)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:686)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.test.SpringApplicationContextLoader.loadContext(SpringApplicationContextLoader.java:100)
    at org.springframework.test.context.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:68)
    at org.springframework.test.context.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:86)
    at org.springframework.test.context.DefaultTestContext.getApplicationContext(DefaultTestContext.java:72)
    at org.springframework.test.context.web.ServletTestExecutionListener.setUpRequestContextIfNecessary(ServletTestExecutionListener.java:170)
    at org.springframework.test.context.web.ServletTestExecutionListener.prepareTestInstance(ServletTestExecutionListener.java:110)
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:212)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:200)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:259)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:261)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:219)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:83)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:68)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:163)
    at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassExecuter.runTestClass(JUnitTestClassExecuter.java:86)
    at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassExecuter.execute(JUnitTestClassExecuter.java:49)
    at org.gradle.api.internal.tasks.testing.junit.JUnitTestClassProcessor.processTestClass(JUnitTestClassProcessor.java:69)
    at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.processTestClass(SuiteTestClassProcessor.java:48)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
    at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
    at org.gradle.messaging.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:32)
    at org.gradle.messaging.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:93)
    at com.sun.proxy.$Proxy2.processTestClass(Unknown Source)
    at org.gradle.api.internal.tasks.testing.worker.TestWorker.processTestClass(TestWorker.java:105)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
    at org.gradle.messaging.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
    at org.gradle.messaging.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:355)
    at org.gradle.internal.concurrent.DefaultExecutorFactory$StoppableExecutorImpl$1.run(DefaultExecutorFactory.java:64)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.catalina.LifecycleException: service.getName(): "Tomcat";  Protocol handler start failed
    at org.apache.catalina.connector.Connector.startInternal(Connector.java:993)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    ... 61 common frames omitted
Caused by: java.net.BindException: Address already in use: bind
    at sun.nio.ch.Net.bind0(Native Method)
    at sun.nio.ch.Net.bind(Net.java:436)
    at sun.nio.ch.Net.bind(Net.java:428)
    at sun.nio.ch.ServerSocketChannelImpl.bind(ServerSocketChannelImpl.java:214)
    at sun.nio.ch.ServerSocketAdaptor.bind(ServerSocketAdaptor.java:74)
    at org.apache.tomcat.util.net.NioEndpoint.bind(NioEndpoint.java:343)
    at org.apache.tomcat.util.net.AbstractEndpoint.start(AbstractEndpoint.java:739)
    at org.apache.coyote.AbstractProtocol.start(AbstractProtocol.java:472)
    at org.apache.coyote.http11.Http11NioProtocol.start(Http11NioProtocol.java:81)
    at org.apache.catalina.connector.Connector.startInternal(Connector.java:986)
    ... 62 common frames omitted

Gradle is spinning up another instance of the embedded Tomcat server, causing the bind exception. Adding the -debug flag to Gradle's execution revealed this.

Gradle's test, forEvery property which defaults to 0 (no maximum). It's described here as

"The maximum number of test classes to execute in a forked test process. The forked test process will be restarted when this limit is reached. The default value is 0 (no maximum)."

The JUnit tests are being executed in parallel, and due to multiple controller tests which required an application context to run, the same port is being used on Tomcat initialization.

One could get away with adding the following to build.gradle, though it would significantly slow tests:

build.gradle:

test{

    forkEvery = 1
}

Instead, simply override the Tomcat server port, as documented here, in the alternate properties file to have Tomcat initialize itself with an unused port each time it spun up.

application-junit.properties:

server.port=0