我是 Selenium 的新手，我正在尝试自动化应用程序，当我运行我的代码时，我遇到如下异常：
错误日志：
org.openqa.selenium.remote.UnreachableBrowserException: Error communicating with the remote browser. It may have died. Build info: version: '2.37.0', revision: 'a7c61cb', time: '2013-10-18 17:14:00' System info: host: 'HW0645', ip: '172.16.6.254', os.name: 'Windows 7', os.arch: 'x86', os.version: '6.1', java.version: '1.6.0_20' Driver info: driver.version: RemoteWebDriver
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:548)
at org.openqa.selenium.remote.RemoteWebDriver.get(RemoteWebDriver.java:276)
at pack.MobileApp.testAndriod_Test(MobileApp.java:34)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
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.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197) Caused by: org.apache.http.NoHttpResponseException: The target server failed to respond
at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:143)
at org.apache.http.impl.conn.DefaultHttpResponseParser.parseHead(DefaultHttpResponseParser.java:57)
at org.apache.http.impl.io.AbstractMessageParser.parse(AbstractMessageParser.java:260)
at org.apache.http.impl.AbstractHttpClientConnection.receiveResponseHeader(AbstractHttpClientConnection.java:283)
at org.apache.http.impl.conn.DefaultClientConnection.receiveResponseHeader(DefaultClientConnection.java:251)
at org.apache.http.impl.conn.AbstractClientConnAdapter.receiveResponseHeader(AbstractClientConnAdapter.java:223)
at org.apache.http.protocol.HttpRequestExecutor.doReceiveResponse(HttpRequestExecutor.java:271)
at org.apache.http.protocol.HttpRequestExecutor.execute(HttpRequestExecutor.java:123)
at org.apache.http.impl.client.DefaultRequestDirector.tryExecute(DefaultRequestDirector.java:682)
at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:486)
at org.apache.http.impl.client.AbstractHttpClient.doExecute(AbstractHttpClient.java:863)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:72)
at org.apache.http.impl.client.CloseableHttpClient.execute(CloseableHttpClient.java:57)
at org.openqa.selenium.remote.HttpCommandExecutor.fallBackExecute(HttpCommandExecutor.java:337)
at org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:298)
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:527) ... 27 more org.openqa.selenium.WebDriverException: No open windows. Build info: version: 'unknown', revision: 'unknown', time: 'unknown' System info: os.name: 'Linux', os.arch: 'armv7l', os.version: '2.6.29-gea477bb', java.version: '0' Driver info: driver.version: EventFiringWebDriver Command duration or timeout: 9.83 seconds Build info: version: '2.37.0', revision: 'a7c61cb', time: '2013-10-18 17:14:00' System info: host: 'HW0645', ip: '172.16.6.254', os.name: 'Windows 7', os.arch: 'x86', os.version: '6.1', java.version: '1.6.0_20' Session ID: 497a4d10-e31f-4b5a-9e83-3982ef07edfa Driver info: org.openqa.selenium.android.AndroidDriver Capabilities [{platform=ANDROID, javascriptEnabled=true, acceptSslCerts=true, browserName=android, rotatable=true, locationContextEnabled=true, webdriver.remote.sessionid=497a4d10-e31f-4b5a-9e83-3982ef07edfa, version=18, handlesAlerts=true, browserConnectionEnabled=true, webStorageEnabled=true, applicationCacheEnabled=true, takesScreenshot=true}]
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
at java.lang.reflect.Constructor.newInstance(Unknown Source)
at org.openqa.selenium.remote.ErrorHandler.createThrowable(ErrorHandler.java:193)
at org.openqa.selenium.remote.ErrorHandler.throwIfResponseFailed(ErrorHandler.java:145)
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:554)
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:569)
at org.openqa.selenium.remote.RemoteWebDriver.close(RemoteWebDriver.java:418)
at pack.MobileApp.tearDown(MobileApp.java:28)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:33)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
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.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197) Caused by: org.openqa.selenium.WebDriverException: No open windows. Build info: version: 'unknown', revision: 'unknown', time: 'unknown' System info: os.name: 'Linux', os.arch: 'armv7l', os.version: '2.6.29-gea477bb', java.version: '0' Driver info: driver.version: EventFiringWebDriver Build info: version: '2.37.0', revision: 'a7c61cb', time: '2013-10-18 17:14:00' System info: host: 'HW0645', ip: '172.16.6.254', os.name: 'Windows 7', os.arch: 'x86', os.version: '6.1', java.version: '1.6.0_20' Driver info: driver.version: EventFiringWebDriver
at org.openqa.selenium.android.library.AndroidWebDriver.close(AndroidWebDriver.java:472)
at org.openqa.selenium.android.AndroidApkDriver.close(AndroidApkDriver.java:78)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at org.openqa.selenium.support.events.EventFiringWebDriver$2.invoke(EventFiringWebDriver.java:101)
at $Proxy1.close(Native Method)
at org.openqa.selenium.support.events.EventFiringWebDriver.close(EventFiringWebDriver.java:190)
at org.openqa.selenium.remote.server.handler.CloseWindow.call(CloseWindow.java:32)
at org.openqa.selenium.remote.server.handler.CloseWindow.call(CloseWindow.java:1)
at java.util.concurrent.FutureTask.run(FutureTask.java:234)
at org.openqa.selenium.remote.server.DefaultSession$1.run(DefaultSession.java:169)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1080)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:573)
at java.lang.Thread.run(Thread.java:841)