我想更新Eclipse版本。 系统报告弹出窗口：
无法读取http://www.eclipse.org/downloads/packages/release/photon/r/eclipse-ide-java-ee-developers处的存储库。 http://www.eclipse.org/downloads/packages/release/photon/r/eclipse-ide-java-ee-developers不是有效的存储库位置。
出现问题说：
An error occurred while collecting items to be installed
session context was:(profile=C__Users_Lukas_eclipse_committers-photon_eclipse, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
No repository found containing: osgi.bundle,org.eclipse.egit,5.2.0.201809290756
No repository found containing: osgi.bundle,org.eclipse.egit.core,5.2.0.201809290756
No repository found containing: osgi.bundle,org.eclipse.egit.doc,5.2.0.201809290756
No repository found containing: osgi.bundle,org.eclipse.egit.gitflow,5.2.0.201809290756
No repository found containing: osgi.bundle,org.eclipse.egit.gitflow.ui,5.2.0.201809290756
No repository found containing: osgi.bundle,org.eclipse.egit.mylyn.ui,5.2.0.201809290756
No repository found containing: osgi.bundle,org.eclipse.egit.ui,5.2.0.201809290756
No repository found containing: osgi.bundle,org.eclipse.jgit.archive,5.2.0.201809280023
No repository found containing: org.eclipse.update.feature,org.eclipse.egit,5.2.0.201809290756
No repository found containing: org.eclipse.update.feature,org.eclipse.egit.gitflow.feature,5.2.0.201809290756
No repository found containing: org.eclipse.update.feature,org.eclipse.egit.mylyn,5.2.0.201809290756
No repository found containing: osgi.bundle,org.eclipse.jgit,5.2.0.201809280023
No repository found containing: org.eclipse.update.feature,org.eclipse.jgit,5.2.0.201809280042
我该如何解决？