selenium连续执行用例的时候报session id is null错误

wuxi88

有多个测试脚本，连续跑下去的过程中，时不时的就会出现如下错误，请问下该如何解决呢？
org.openqa.selenium.remote.SessionNotFoundException: Session ID is null. Using WebDriver after calling quit()?Build info: version: '2.43.1', revision: '5163bce', time: '2014-09-10 16:27:58'System info: host: 'Windows2012R2', ip: '10.10.126.158', os.name: 'Windows Server 2012 R2', os.arch: 'amd64', os.version: '6.3', java.version: '1.8.0_25'Driver info: driver.version: RemoteWebDriver        at org.openqa.selenium.remote.HttpCommandExecutor.execute(HttpCommandExecutor.java:158)        at org.openqa.selenium.remote.service.DriverCommandExecutor.execute(DriverCommandExecutor.java:66)        at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:572)        at org.openqa.selenium.remote.RemoteWebDriver.get(RemoteWebDriver.java:304)        at envchange.NormalAndTestEnvPub.isTestEnvAct(Unknown Source)        at listmanagement.ImportUser.importUser(Unknown Source)... Removed 23 stack frames