我使用的是 Selenium 3.4.0、Java 1.8 和 Firefox 54.0.1(64 位)。当我尝试使用 Firefox 打开链接时，出现空指针异常。当我使用 Selenium/Python 时，它工作正常，但我试图运行此 guru 99 页中的代码( https://www.guru99.com/first-webdriver-script.html).I '已经搜索以查看其他人是否遇到此问题，但我找不到任何解决方案。我得到以下输出:
1501246654252 addons.manager DEBUG Application has been upgraded
1501246654291 addons.manager DEBUG Loaded provider scope for resource://gre/modules/addons/XPIProvider.jsm: ["XPIProvider"]
1501246654293 addons.manager DEBUG Loaded provider scope for resource://gre/modules/LightweightThemeManager.jsm: ["LightweightThemeManager"]
1501246654297 addons.manager DEBUG Loaded provider scope for resource://gre/modules/addons/GMPProvider.jsm
1501246654299 addons.manager DEBUG Loaded provider scope for resource://gre/modules/addons/PluginProvider.jsm
1501246654299 addons.manager DEBUG Starting provider: XPIProvider
1501246654300 addons.xpi DEBUG startup
1501246654301 addons.xpi INFO Mapping fxdriver@googlecode.com to C:\Users\CHRISG~1\AppData\Local\Temp\anonymous8191426632770324153webdriver-profile\extensions\fxdriver@googlecode.com
1501246654301 addons.xpi DEBUG Ignoring file entry whose name is not a valid add-on ID: C:\Users\CHRISG~1\AppData\Local\Temp\anonymous8191426632770324153webdriver-profile\extensions\webdriver-staging
1501246654301 addons.xpi INFO Removing all system add-on upgrades.
1501246654301 addons.xpi INFO SystemAddonInstallLocation directory is missing
1501246654302 addons.xpi INFO Mapping aushelper@mozilla.org to C:\Program Files\Mozilla Firefox\browser\features\aushelper@mozilla.org.xpi
1501246654303 addons.xpi INFO Mapping e10srollout@mozilla.org to C:\Program Files\Mozilla Firefox\browser\features\e10srollout@mozilla.org.xpi
1501246654303 addons.xpi INFO Mapping firefox@getpocket.com to C:\Program Files\Mozilla Firefox\browser\features\firefox@getpocket.com.xpi
1501246654303 addons.xpi INFO Mapping screenshots@mozilla.org to C:\Program Files\Mozilla Firefox\browser\features\screenshots@mozilla.org.xpi
1501246654304 addons.xpi INFO Mapping webcompat@mozilla.org to C:\Program Files\Mozilla Firefox\browser\features\webcompat@mozilla.org.xpi
1501246654305 addons.xpi INFO Mapping {972ce4c6-7e08-4474-a285-3208198ce6fd} to C:\Program Files\Mozilla Firefox\browser\extensions\{972ce4c6-7e08-4474-a285-3208198ce6fd}.xpi
1501246654305 addons.xpi DEBUG Skipping unavailable install location app-system-share
1501246654305 addons.xpi DEBUG Skipping unavailable install location app-system-local
1501246654306 addons.xpi DEBUG checkForChanges
1501246654306 addons.xpi INFO SystemAddonInstallLocation directory is missing
1501246654307 addons.xpi DEBUG Loaded add-on state from prefs: {}
1501246654308 addons.xpi DEBUG New add-on fxdriver@googlecode.com in app-profile
1501246654308 addons.xpi DEBUG getModTime: Recursive scan of fxdriver@googlecode.com
1501246654313 addons.xpi DEBUG New add-on aushelper@mozilla.org in app-system-defaults
1501246654313 addons.xpi DEBUG getModTime: Recursive scan of aushelper@mozilla.org
1501246654314 addons.xpi DEBUG New add-on e10srollout@mozilla.org in app-system-defaults
1501246654315 addons.xpi DEBUG getModTime: Recursive scan of e10srollout@mozilla.org
1501246654315 addons.xpi DEBUG New add-on firefox@getpocket.com in app-system-defaults
1501246654315 addons.xpi DEBUG getModTime: Recursive scan of firefox@getpocket.com
1501246654315 addons.xpi DEBUG New add-on screenshots@mozilla.org in app-system-defaults
1501246654316 addons.xpi DEBUG getModTime: Recursive scan of screenshots@mozilla.org
1501246654316 addons.xpi DEBUG New add-on webcompat@mozilla.org in app-system-defaults
1501246654316 addons.xpi DEBUG getModTime: Recursive scan of webcompat@mozilla.org
1501246654317 addons.xpi DEBUG New add-on {972ce4c6-7e08-4474-a285-3208198ce6fd} in app-global
1501246654317 addons.xpi DEBUG getModTime: Recursive scan of {972ce4c6-7e08-4474-a285-3208198ce6fd}
1501246654317 addons.xpi DEBUG getInstallState changed: true, state: {"app-profile":{"fxdriver@googlecode.com":{"d":"C:\\Users\\CHRISG~1\\AppData\\Local\\Temp\\anonymous8191426632770324153webdriver-profile\\extensions\\fxdriver@googlecode.com","st":1501246654037,"mt":1501246653985}},"app-system-defaults":{"aushelper@mozilla.org":{"d":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\aushelper@mozilla.org.xpi","st":1498667065000},"e10srollout@mozilla.org":{"d":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\e10srollout@mozilla.org.xpi","st":1498667065000},"firefox@getpocket.com":{"d":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\firefox@getpocket.com.xpi","st":1498667066000},"screenshots@mozilla.org":{"d":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\screenshots@mozilla.org.xpi","st":1498667067000},"webcompat@mozilla.org":{"d":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\webcompat@mozilla.org.xpi","st":1498667066000}},"app-global":{"{972ce4c6-7e08-4474-a285-3208198ce6fd}":{"d":"C:\\Program Files\\Mozilla Firefox\\browser\\extensions\\{972ce4c6-7e08-4474-a285-3208198ce6fd}.xpi","st":1498667065000}}}
1501246654324 addons.xpi-utils DEBUG Opening XPI database C:\Users\CHRISG~1\AppData\Local\Temp\anonymous8191426632770324153webdriver-profile\extensions.json
1501246654326 addons.xpi-utils DEBUG New add-on fxdriver@googlecode.com installed in app-profile
*** Blocklist::_loadBlocklistFromFile: blocklist is disabled
1501246654340 addons.xpi WARN Add-on fxdriver@googlecode.com is not correctly signed.
1501246654340 addons.xpi WARN Add-on fxdriver@googlecode.com is not correctly signed.
1501246654343 DeferredSave.extensions.json DEBUG Save changes
1501246654343 addons.xpi-utils DEBUG New add-on aushelper@mozilla.org installed in app-system-defaults
1501246654346 DeferredSave.extensions.json DEBUG Starting timer
1501246654349 DeferredSave.extensions.json DEBUG Save changes
1501246654349 addons.xpi-utils DEBUG New add-on e10srollout@mozilla.org installed in app-system-defaults
1501246654354 DeferredSave.extensions.json DEBUG Save changes
1501246654355 addons.xpi-utils DEBUG New add-on firefox@getpocket.com installed in app-system-defaults
1501246654359 DeferredSave.extensions.json DEBUG Save changes
1501246654359 addons.xpi-utils DEBUG New add-on screenshots@mozilla.org installed in app-system-defaults
1501246654365 DeferredSave.extensions.json DEBUG Save changes
1501246654365 addons.xpi-utils DEBUG New add-on webcompat@mozilla.org installed in app-system-defaults
1501246654369 DeferredSave.extensions.json DEBUG Save changes
1501246654370 addons.xpi-utils DEBUG New add-on {972ce4c6-7e08-4474-a285-3208198ce6fd} installed in app-global
1501246654373 DeferredSave.extensions.json DEBUG Starting write
1501246654379 DeferredSave.extensions.json DEBUG Save changes
1501246654380 DeferredSave.extensions.json DEBUG Data changed while write in progress
1501246654380 addons.manager DEBUG Registering startup change 'installed' for fxdriver@googlecode.com
1501246654380 addons.xpi-utils DEBUG Make addon app-profile:fxdriver@googlecode.com visible
1501246654381 DeferredSave.extensions.json DEBUG Save changes
1501246654381 addons.manager DEBUG Registering startup change 'installed' for aushelper@mozilla.org
1501246654390 addons.xpi DEBUG Loading bootstrap scope from C:\Program Files\Mozilla Firefox\browser\features\aushelper@mozilla.org.xpi
1501246654394 addons.xpi DEBUG Calling bootstrap method install on aushelper@mozilla.org version 2.0
1501246654395 addons.xpi-utils DEBUG Make addon app-system-defaults:aushelper@mozilla.org visible
1501246654395 DeferredSave.extensions.json DEBUG Save changes
1501246654395 addons.manager DEBUG Registering startup change 'installed' for e10srollout@mozilla.org
1501246654396 addons.xpi DEBUG Loading bootstrap scope from C:\Program Files\Mozilla Firefox\browser\features\e10srollout@mozilla.org.xpi
1501246654399 addons.xpi DEBUG Calling bootstrap method install on e10srollout@mozilla.org version 1.50
1501246654400 addons.xpi-utils DEBUG Make addon app-system-defaults:e10srollout@mozilla.org visible
1501246654400 DeferredSave.extensions.json DEBUG Save changes
1501246654400 addons.manager DEBUG Registering startup change 'installed' for firefox@getpocket.com
1501246654401 addons.xpi DEBUG Loading bootstrap scope from C:\Program Files\Mozilla Firefox\browser\features\firefox@getpocket.com.xpi
1501246654405 addons.xpi DEBUG Calling bootstrap method install on firefox@getpocket.com version 1.0.5
1501246654405 addons.xpi-utils DEBUG Make addon app-system-defaults:firefox@getpocket.com visible
1501246654406 DeferredSave.extensions.json DEBUG Save changes
1501246654406 addons.manager DEBUG Registering startup change 'installed' for screenshots@mozilla.org
1501246654407 addons.xpi DEBUG Loading bootstrap scope from C:\Program Files\Mozilla Firefox\browser\features\screenshots@mozilla.org.xpi
1501246654410 addons.xpi DEBUG Calling bootstrap method install on screenshots@mozilla.org version 6.6.0
1501246654410 addons.xpi-utils DEBUG Make addon app-system-defaults:screenshots@mozilla.org visible
1501246654410 DeferredSave.extensions.json DEBUG Save changes
1501246654410 addons.manager DEBUG Registering startup change 'installed' for webcompat@mozilla.org
1501246654411 addons.xpi DEBUG Loading bootstrap scope from C:\Program Files\Mozilla Firefox\browser\features\webcompat@mozilla.org.xpi
1501246654413 addons.xpi DEBUG Calling bootstrap method install on webcompat@mozilla.org version 1.1
1501246654413 addons.xpi-utils DEBUG Make addon app-system-defaults:webcompat@mozilla.org visible
1501246654413 DeferredSave.extensions.json DEBUG Save changes
1501246654414 addons.xpi-utils DEBUG Make addon app-global:{972ce4c6-7e08-4474-a285-3208198ce6fd} visible
1501246654414 DeferredSave.extensions.json DEBUG Save changes
1501246654414 addons.xpi DEBUG Updating XPIState for {"id":"fxdriver@googlecode.com","syncGUID":"{284a66e3-05a6-4d03-b43d-a92a5f93e2f7}","location":"app-profile","version":"3.4.0","type":"extension","internalName":null,"updateURL":null,"updateKey":null,"optionsURL":null,"optionsType":null,"aboutURL":null,"icons":{},"iconURL":null,"icon64URL":null,"defaultLocale":{"name":"Firefox WebDriver","description":"WebDriver implementation for Firefox","creator":"Simon Stewart","homepageURL":null},"visible":true,"active":false,"userDisabled":false,"appDisabled":true,"descriptor":"C:\\Users\\CHRISG~1\\AppData\\Local\\Temp\\anonymous8191426632770324153webdriver-profile\\extensions\\fxdriver@googlecode.com","installDate":1501246654037,"updateDate":1501246654037,"applyBackgroundUpdates":1,"bootstrap":false,"skinnable":false,"size":3303362,"sourceURI":null,"releaseNotesURI":null,"softDisabled":false,"foreignInstall":true,"hasBinaryComponents":false,"strictCompatibility":false,"locales":[],"targetApplications":[{"id":"{ec8030f7-c20a-464f-9b0e-13a3a9e97384}","minVersion":"3.0","maxVersion":"48.0"}],"targetPlatforms":[{"os":"Darwin","abi":null},{"os":"SunOS","abi":null},{"os":"FreeBSD","abi":null},{"os":"OpenBSD","abi":null},{"os":"WINNT","abi":null},{"os":"Linux","abi":null}],"multiprocessCompatible":false,"signedState":0,"seen":true,"dependencies":[],"hasEmbeddedWebExtension":false,"mpcOptedOut":false,"userPermissions":null}
1501246654415 addons.xpi DEBUG Updating XPIState for {"id":"aushelper@mozilla.org","syncGUID":"{a337c938-f101-467f-8334-642c2957ef77}","location":"app-system-defaults","version":"2.0","type":"extension","internalName":null,"updateURL":null,"updateKey":null,"optionsURL":null,"optionsType":null,"aboutURL":null,"icons":{},"iconURL":null,"icon64URL":null,"defaultLocale":{"name":"Application Update Service Helper","description":"Sets value(s) in the update url based on custom checks.","creator":null,"homepageURL":null},"visible":true,"active":true,"userDisabled":false,"appDisabled":false,"descriptor":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\aushelper@mozilla.org.xpi","installDate":1498667065000,"updateDate":1498667065000,"applyBackgroundUpdates":1,"bootstrap":true,"skinnable":false,"size":8488,"sourceURI":null,"releaseNotesURI":null,"softDisabled":false,"foreignInstall":false,"hasBinaryComponents":false,"strictCompatibility":false,"locales":[],"targetApplications":[{"id":"{ec8030f7-c20a-464f-9b0e-13a3a9e97384}","minVersion":"54.0.1","maxVersion":"54.*"}],"targetPlatforms":[],"multiprocessCompatible":true,"seen":true,"dependencies":[],"hasEmbeddedWebExtension":false,"mpcOptedOut":false,"userPermissions":null}
1501246654415 addons.xpi DEBUG getModTime: Recursive scan of aushelper@mozilla.org
1501246654415 addons.xpi DEBUG Updating XPIState for {"id":"e10srollout@mozilla.org","syncGUID":"{253d1e2b-244f-48a3-8215-48fd1ea043b0}","location":"app-system-defaults","version":"1.50","type":"extension","internalName":null,"updateURL":null,"updateKey":null,"optionsURL":null,"optionsType":null,"aboutURL":null,"icons":{},"iconURL":null,"icon64URL":null,"defaultLocale":{"name":"Multi-process staged rollout","description":"Staged rollout of Firefox multi-process feature.","creator":null,"homepageURL":null},"visible":true,"active":true,"userDisabled":false,"appDisabled":false,"descriptor":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\e10srollout@mozilla.org.xpi","installDate":1498667065000,"updateDate":1498667065000,"applyBackgroundUpdates":1,"bootstrap":true,"skinnable":false,"size":12519,"sourceURI":null,"releaseNotesURI":null,"softDisabled":false,"foreignInstall":false,"hasBinaryComponents":false,"strictCompatibility":false,"locales":[],"targetApplications":[{"id":"{ec8030f7-c20a-464f-9b0e-13a3a9e97384}","minVersion":"54.0.1","maxVersion":"54.*"}],"targetPlatforms":[],"multiprocessCompatible":true,"seen":true,"dependencies":[],"hasEmbeddedWebExtension":false,"mpcOptedOut":false,"userPermissions":null}
1501246654415 addons.xpi DEBUG getModTime: Recursive scan of e10srollout@mozilla.org
1501246654416 addons.xpi DEBUG Updating XPIState for {"id":"firefox@getpocket.com","syncGUID":"{82e97246-464d-494a-92d5-df6243a967d5}","location":"app-system-defaults","version":"1.0.5","type":"extension","internalName":null,"updateURL":null,"updateKey":null,"optionsURL":null,"optionsType":null,"aboutURL":null,"icons":{},"iconURL":null,"icon64URL":null,"defaultLocale":{"name":"Pocket","description":"When you find something you want to view later, put it in Pocket.","creator":null,"homepageURL":null},"visible":true,"active":true,"userDisabled":false,"appDisabled":false,"descriptor":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\firefox@getpocket.com.xpi","installDate":1498667066000,"updateDate":1498667066000,"applyBackgroundUpdates":1,"bootstrap":true,"skinnable":false,"size":913906,"sourceURI":null,"releaseNotesURI":null,"softDisabled":false,"foreignInstall":false,"hasBinaryComponents":false,"strictCompatibility":false,"locales":[],"targetApplications":[{"id":"{ec8030f7-c20a-464f-9b0e-13a3a9e97384}","minVersion":"54.0.1","maxVersion":"54.*"}],"targetPlatforms":[],"multiprocessCompatible":true,"seen":true,"dependencies":[],"hasEmbeddedWebExtension":false,"mpcOptedOut":false,"userPermissions":null}
1501246654416 addons.xpi DEBUG getModTime: Recursive scan of firefox@getpocket.com
1501246654417 addons.xpi DEBUG Updating XPIState for {"id":"screenshots@mozilla.org","syncGUID":"{88407b9c-4ff8-4d68-9615-aa613dbe559f}","location":"app-system-defaults","version":"6.6.0","type":"extension","internalName":null,"updateURL":null,"updateKey":null,"optionsURL":null,"optionsType":null,"aboutURL":null,"icons":{},"iconURL":null,"icon64URL":null,"defaultLocale":{"name":"Firefox Screenshots","description":null,"creator":null,"homepageURL":"https://pageshot.net/"},"visible":true,"active":true,"userDisabled":false,"appDisabled":false,"descriptor":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\screenshots@mozilla.org.xpi","installDate":1498667067000,"updateDate":1498667067000,"applyBackgroundUpdates":1,"bootstrap":true,"skinnable":false,"size":716271,"sourceURI":null,"releaseNotesURI":null,"softDisabled":false,"foreignInstall":false,"hasBinaryComponents":false,"strictCompatibility":false,"locales":[],"targetApplications":[{"id":"{ec8030f7-c20a-464f-9b0e-13a3a9e97384}","minVersion":"51.0a1","maxVersion":"*"}],"targetPlatforms":[],"multiprocessCompatible":true,"seen":true,"dependencies":[],"hasEmbeddedWebExtension":false,"mpcOptedOut":false,"userPermissions":null}
1501246654417 addons.xpi DEBUG getModTime: Recursive scan of screenshots@mozilla.org
1501246654418 addons.xpi DEBUG Updating XPIState for {"id":"webcompat@mozilla.org","syncGUID":"{21466d10-4f5e-4882-9e6b-1d1c096fc15b}","location":"app-system-defaults","version":"1.1","type":"extension","internalName":null,"updateURL":null,"updateKey":null,"optionsURL":null,"optionsType":null,"aboutURL":null,"icons":{},"iconURL":null,"icon64URL":null,"defaultLocale":{"name":"Web Compat","description":"Urgent post-release fixes for web compatibility.","creator":null,"homepageURL":null},"visible":true,"active":true,"userDisabled":false,"appDisabled":false,"descriptor":"C:\\Program Files\\Mozilla Firefox\\browser\\features\\webcompat@mozilla.org.xpi","installDate":1498667066000,"updateDate":1498667066000,"applyBackgroundUpdates":1,"bootstrap":true,"skinnable":false,"size":9006,"sourceURI":null,"releaseNotesURI":null,"softDisabled":false,"foreignInstall":false,"hasBinaryComponents":false,"strictCompatibility":false,"locales":[],"targetApplications":[{"id":"{ec8030f7-c20a-464f-9b0e-13a3a9e97384}","minVersion":"54.0.1","maxVersion":"54.*"}],"targetPlatforms":[],"multiprocessCompatible":true,"seen":true,"dependencies":[],"hasEmbeddedWebExtension":false,"mpcOptedOut":false,"userPermissions":null}
1501246654418 addons.xpi DEBUG getModTime: Recursive scan of webcompat@mozilla.org
1501246654419 addons.xpi DEBUG Updating XPIState for {"id":"{972ce4c6-7e08-4474-a285-3208198ce6fd}","syncGUID":"{374c68bf-b5ce-4e4f-a6c4-f1532a743336}","location":"app-global","version":"54.0.1","type":"theme","internalName":"classic/1.0","updateURL":null,"updateKey":null,"optionsURL":null,"optionsType":null,"aboutURL":null,"icons":{},"iconURL":"chrome://browser/content/default-theme-icon.svg","icon64URL":null,"defaultLocale":{"name":"Default","description":"The default theme.","creator":"Mozilla","homepageURL":null,"contributors":["Mozilla Contributors"]},"visible":true,"active":true,"userDisabled":false,"appDisabled":false,"descriptor":"C:\\Program Files\\Mozilla Firefox\\browser\\extensions\\{972ce4c6-7e08-4474-a285-3208198ce6fd}.xpi","installDate":1498667065000,"updateDate":1498667065000,"applyBackgroundUpdates":1,"skinnable":true,"size":8207,"sourceURI":null,"releaseNotesURI":null,"softDisabled":false,"foreignInstall":false,"hasBinaryComponents":false,"strictCompatibility":true,"locales":[],"targetApplications":[{"id":"{ec8030f7-c20a-464f-9b0e-13a3a9e97384}","minVersion":"54.0.1","maxVersion":"54.0.1"}],"targetPlatforms":[],"seen":true,"dependencies":[],"hasEmbeddedWebExtension":false,"userPermissions":null}
1501246654420 addons.xpi DEBUG getModTime: Recursive scan of {972ce4c6-7e08-4474-a285-3208198ce6fd}
1501246654444 DeferredSave.extensions.json DEBUG Save changes
1501246654444 addons.xpi DEBUG Updating database with changes to installed add-ons
1501246654444 addons.xpi-utils DEBUG Updating add-on states
1501246654445 addons.xpi-utils DEBUG Writing add-ons list
1501246654452 addons.xpi DEBUG Registering manifest for C:\Program Files\Mozilla Firefox\browser\features\aushelper@mozilla.org.xpi
1501246654452 addons.xpi DEBUG Calling bootstrap method startup on aushelper@mozilla.org version 2.0
1501246654453 addons.xpi DEBUG Registering manifest for C:\Program Files\Mozilla Firefox\browser\features\e10srollout@mozilla.org.xpi
1501246654454 addons.xpi DEBUG Calling bootstrap method startup on e10srollout@mozilla.org version 1.50
1501246654455 addons.xpi DEBUG Registering manifest for C:\Program Files\Mozilla Firefox\browser\features\firefox@getpocket.com.xpi
1501246654456 addons.xpi DEBUG Calling bootstrap method startup on firefox@getpocket.com version 1.0.5
1501246654456 addons.xpi DEBUG Registering manifest for C:\Program Files\Mozilla Firefox\browser\features\screenshots@mozilla.org.xpi
1501246654457 addons.xpi DEBUG Calling bootstrap method startup on screenshots@mozilla.org version 6.6.0
1501246654457 addons.xpi DEBUG Registering manifest for C:\Program Files\Mozilla Firefox\browser\features\webcompat@mozilla.org.xpi
1501246654458 addons.xpi DEBUG Calling bootstrap method startup on webcompat@mozilla.org version 1.1
1501246654461 addons.manager DEBUG Registering shutdown blocker for XPIProvider
1501246654462 addons.manager DEBUG Provider finished startup: XPIProvider
1501246654462 addons.manager DEBUG Starting provider: LightweightThemeManager
1501246654462 addons.manager DEBUG Registering shutdown blocker for LightweightThemeManager
1501246654462 addons.manager DEBUG Provider finished startup: LightweightThemeManager
1501246654462 addons.manager DEBUG Starting provider: GMPProvider
1501246654467 addons.manager DEBUG Registering shutdown blocker for GMPProvider
1501246654467 addons.manager DEBUG Provider finished startup: GMPProvider
1501246654467 addons.manager DEBUG Starting provider: PluginProvider
1501246654467 addons.manager DEBUG Registering shutdown blocker for PluginProvider
1501246654467 addons.manager DEBUG Provider finished startup: PluginProvider
1501246654468 addons.manager DEBUG Completed startup sequence
1501246654778 addons.manager DEBUG Starting provider: <unnamed-provider>
1501246654778 addons.manager DEBUG Registering shutdown blocker for <unnamed-provider>
1501246654779 addons.manager DEBUG Provider finished startup: <unnamed-provider>
1501246654937 DeferredSave.extensions.json DEBUG Write succeeded
1501246654937 addons.xpi-utils DEBUG XPI Database saved, setting schema version preference to 19
1501246654937 DeferredSave.extensions.json DEBUG Starting timer
1501246654951 addons.repository DEBUG No addons.json found.
1501246654951 DeferredSave.addons.json DEBUG Save changes
1501246654954 DeferredSave.addons.json DEBUG Starting timer
1501246654976 addons.manager DEBUG Starting provider: PreviousExperimentProvider
1501246654976 addons.manager DEBUG Registering shutdown blocker for PreviousExperimentProvider
1501246654976 addons.manager DEBUG Provider finished startup: PreviousExperimentProvider
1501246654979 DeferredSave.extensions.json DEBUG Starting write
1501246655004 DeferredSave.addons.json DEBUG Starting write
1501246655006 DeferredSave.extensions.json DEBUG Write succeeded
1501246655021 DeferredSave.addons.json DEBUG Write succeeded
[GPU 7220] WARNING: pipe error: 109: file c:/builds/moz2_slave/m-rel-w64-00000000000000000000/build/src/ipc/chromium/src/chrome/common/ipc_channel_win.cc, line 346
Exception in thread "main" org.openqa.selenium.remote.UnreachableBrowserException: Could not start a new session. Possible causes are invalid address of the remote server or browser start-up failure.
Build info: version: 'unknown', revision: 'unknown', time: 'unknown'
System info: host: 'CHRIS-PC', ip: '192.xxx.x.xxx', os.name: 'Windows 10', os.arch: 'amd64', os.version: '10.0', java.version: '1.8.0_141'
Driver info: driver.version: FirefoxDriver
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:658)
at org.openqa.selenium.remote.RemoteWebDriver.startSession(RemoteWebDriver.java:250)
at org.openqa.selenium.remote.RemoteWebDriver.startSession(RemoteWebDriver.java:236)
at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:137)
at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:191)
at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:108)
at org.openqa.selenium.firefox.FirefoxDriver.<init>(FirefoxDriver.java:104)
at newpackage.MyClass.main(MyClass.java:12)
Caused by: java.lang.NullPointerException
at org.openqa.selenium.remote.service.DriverService.waitUntilAvailable(DriverService.java:192)
at org.openqa.selenium.firefox.XpiDriverService.start(XpiDriverService.java:94)
at org.openqa.selenium.remote.service.DriverCommandExecutor.execute(DriverCommandExecutor.java:78)
at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:637)
... 7 more
最佳答案
这是您问题的答案:
错误UnreachableBrowserException:无法启动新 session 。可能的原因是远程服务器地址无效或浏览器启动失败说明了一切。
根据 guru99.com提到在System.setProperty中使用webdriver.firefox.marionette。在 Selenium 3.x 中，我们将改用 webdriver.gecko.driver。
因此请考虑更改代码行:
System.setProperty("webdriver.firefox.marionette","C:\\geckodriver.exe");
至:
System.setProperty("webdriver.gecko.driver","C:\\your_directory\\geckodriver.exe");
如果这能回答您的问题，请告诉我。
关于java - 使用 "webdriver.firefox.marionette"时由 : java. lang.NullPointerException 引起的 UnreachableBrowserException，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/45374301/