org.springframework.web.client.HttpServerErrorException: 500 Internal Server Error

at org.springframework.web.client.DefaultResponseErrorHandler.handleError(DefaultResponseErrorHandler.java:94)
at org.springframework.web.client.RestTemplate.handleResponse(RestTemplate.java:641)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:597)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:572)
at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:493)
at com.cablevision.cas.adc.channel900.Trusted.LogOutWithIndalidSession.setUpClass(LogOutWithIndalidSession.java:51)
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:498)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:86)
at org.testng.internal.Invoker.invokeConfigurationMethod(Invoker.java:514)
at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:215)
at org.testng.internal.Invoker.invokeConfigurations(Invoker.java:142)
at org.testng.internal.TestMethodWorker.invokeBeforeClassMethods(TestMethodWorker.java:178)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:108)
at org.testng.TestRunner.privateRun(TestRunner.java:782)
at org.testng.TestRunner.run(TestRunner.java:632)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:366)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:361)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:319)
at org.testng.SuiteRunner.run(SuiteRunner.java:268)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:86)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1244)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1169)
at org.testng.TestNG.run(TestNG.java:1064)
at org.testng.IDEARemoteTestNG.run(IDEARemoteTestNG.java:72)
at org.testng.RemoteTestNGStarter.main(RemoteTestNGStarter.java:122)
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:498)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)

public class LogOutWithIndalidSession {

static ResponseEntity<String> response;
HttpHeaders headers = new HttpHeaders();
JSONObject request;

@BeforeClass
public void setUpClass() throws URISyntaxException {
    headers.setContentType(MediaType.APPLICATION_JSON);
    request = new JSONObject();
    request.put("sessionId", "41a21846-32f4-42bbfdc9-7442-735679retgfr8ae2aa");

    ClientHttpRequestFactory requestFactory = new
            HttpComponentsClientHttpRequestFactory(HttpClients.createDefault());

    RestTemplate restTemplate = new RestTemplate(requestFactory);

        response = restTemplate.exchange(
                new URI(URL_LOGOUT),
                HttpMethod.POST, new HttpEntity<String>(request.toString(), headers), String.class);

    System.out.println(response.getStatusCode());
}

@Test
public void test(){
      assertThat(response.getStatusCode().value(), is (500));
}