title: org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://localhost:8080/": Connection refused: connect
body: <p>I'm following the official Spring Boot Kotlin guide (<a href="https://spring.io/guides/tutorials/spring-boot-kotlin/" rel="nofollow noreferrer">https://spring.io/guides/tutorials/spring-boot-kotlin/</a>) and I'm hitting a wall. Every time I run the simple TestRestTemplate '/' invoke I get this error:
  <code>org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://localhost:8080/": Connection refused: connect; nested exception is java.net.ConnectException: Connection refused: connect</code></p>
  
  <p>Here's my code:</p>
  
  <pre><code>@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
  class IntegrationTests {
  
      @Test
      fun `Assert blog page title, content and status code`(@Autowired restTemplate: TestRestTemplate) {
          val entity = restTemplate.getForEntity&lt;String&gt;("/")
          Assertions.assertThat(entity.statusCode).isEqualTo(HttpStatus.OK)
          Assertions.assertThat(entity.body).contains("foo")
      }
  }
  </code></pre>
  
  <p>Full error:</p>
  
  <pre><code>I/O error on GET request for "http://localhost:8080/": Connection refused: connect; nested exception is java.net.ConnectException: Connection refused: connect
  org.springframework.web.client.ResourceAccessException: I/O error on GET request for "http://localhost:8080/": Connection refused: connect; nested exception is java.net.ConnectException: Connection refused: connect
      at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:748)
      at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:674)
      at org.springframework.web.client.RestTemplate.getForEntity(RestTemplate.java:342)
      at org.springframework.boot.test.web.client.TestRestTemplate.getForEntity(TestRestTemplate.java:233)
      at com.supaham.learn.spring.IntegrationTests.Assert blog page title, content and status code(IntegrationTests.kt:22)
      at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
      at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.base/java.lang.reflect.Method.invoke(Method.java:567)
      at org.junit.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:675)
      at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
      at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:125)
      at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:132)
      at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:124)
      at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:74)
      at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
      at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
      at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:104)
      at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:62)
      at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:43)
      at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:35)
      at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
      at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
      at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:202)
      at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
      at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:198)
      at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:135)
      at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:69)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135)
      at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
      at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
      at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
      at java.base/java.util.ArrayList.forEach(ArrayList.java:1507)
      at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
      at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
      at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
      at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
      at java.base/java.util.ArrayList.forEach(ArrayList.java:1507)
      at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
      at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
      at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
      at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
      at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
      at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
      at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
      at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
      at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:220)
      at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:188)
      at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:202)
      at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:181)
      at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
      at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.processAllTestClasses(JUnitPlatformTestClassProcessor.java:99)
      at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.access$000(JUnitPlatformTestClassProcessor.java:79)
      at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor.stop(JUnitPlatformTestClassProcessor.java:75)
      at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:61)
      at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
      at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.base/java.lang.reflect.Method.invoke(Method.java:567)
      at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
      at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
      at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:33)
      at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:94)
      at com.sun.proxy.$Proxy2.stop(Unknown Source)
      at org.gradle.api.internal.tasks.testing.worker.TestWorker.stop(TestWorker.java:132)
      at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
      at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.base/java.lang.reflect.Method.invoke(Method.java:567)
      at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
      at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
      at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:182)
      at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:164)
      at org.gradle.internal.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:412)
      at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:64)
      at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:48)
      at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
      at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
      at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:56)
      at java.base/java.lang.Thread.run(Thread.java:830)
  Caused by: java.net.ConnectException: Connection refused: connect
      at java.base/sun.nio.ch.Net.connect0(Native Method)
      at java.base/sun.nio.ch.Net.connect(Net.java:493)
      at java.base/sun.nio.ch.Net.connect(Net.java:482)
      at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:588)
      at java.base/java.net.Socket.connect(Socket.java:603)
      at java.base/java.net.Socket.connect(Socket.java:552)
      at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:182)
      at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:474)
      at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:569)
      at java.base/sun.net.www.http.HttpClient.&lt;init&gt;(HttpClient.java:242)
      at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:341)
      at java.base/sun.net.www.http.HttpClient.New(HttpClient.java:362)
      at java.base/sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(HttpURLConnection.java:1248)
      at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1187)
      at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1081)
      at java.base/sun.net.www.protocol.http.HttpURLConnection.connect(HttpURLConnection.java:1015)
      at org.springframework.http.client.SimpleBufferingClientHttpRequest.executeInternal(SimpleBufferingClientHttpRequest.java:76)
      at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48)
      at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53)
      at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:739)
      ... 92 more
  </code></pre>