Connection refused: connect
class org.xwiki.extension.repository.LocalExtensionRepositoryException: Failed to save extensoin [org.xwiki.platform:xwiki-platform-administration-ui-4.4.1] descriptor
    at org.xwiki.extension.repository.internal.local.DefaultLocalExtensionRepository.storeExtension(DefaultLocalExtensionRepository.java:172)
    at org.xwiki.extension.job.internal.InstallJob.storeExtension(InstallJob.java:157)
    at org.xwiki.extension.job.internal.InstallJob.store(InstallJob.java:145)
    at org.xwiki.extension.job.internal.InstallJob.start(InstallJob.java:118)
    at org.xwiki.job.AbstractJob.start(AbstractJob.java:134)
    at org.xwiki.job.internal.DefaultJobManager.run(DefaultJobManager.java:155)
    at java.lang.Thread.run(Thread.java:722)
Caused by: class java.io.IOException: Failed to request [http://extensions.xwiki.org/xwiki/rest/repository/extensions/org.xwiki.platform%3Axwiki-platform-administration-ui/versions/4.4.1/file]
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionRepository.getRESTResource(XWikiExtensionRepository.java:125)
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionRepository.getRESTResourceAsStream(XWikiExtensionRepository.java:138)
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionFile.openStream(XWikiExtensionFile.java:76)
    at org.xwiki.extension.repository.internal.local.DefaultLocalExtensionRepository.storeExtension(DefaultLocalExtensionRepository.java:159)
    at org.xwiki.extension.job.internal.InstallJob.storeExtension(InstallJob.java:157)
    at org.xwiki.extension.job.internal.InstallJob.store(InstallJob.java:145)
    at org.xwiki.extension.job.internal.InstallJob.start(InstallJob.java:118)
    at org.xwiki.job.AbstractJob.start(AbstractJob.java:134)
    at org.xwiki.job.internal.DefaultJobManager.run(DefaultJobManager.java:155)
    at java.lang.Thread.run(Thread.java:722)
Caused by: class org.apache.http.conn.HttpHostConnectException: Connection to http://extensions.xwiki.org refused
    at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:190)
    at org.apache.http.impl.conn.ManagedClientConnectionImpl.open(ManagedClientConnectionImpl.java:294)
    at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:640)
    at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:479)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:906)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:805)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:784)
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionRepository.getRESTResource(XWikiExtensionRepository.java:123)
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionRepository.getRESTResourceAsStream(XWikiExtensionRepository.java:138)
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionFile.openStream(XWikiExtensionFile.java:76)
    at org.xwiki.extension.repository.internal.local.DefaultLocalExtensionRepository.storeExtension(DefaultLocalExtensionRepository.java:159)
    at org.xwiki.extension.job.internal.InstallJob.storeExtension(InstallJob.java:157)
    at org.xwiki.extension.job.internal.InstallJob.store(InstallJob.java:145)
    at org.xwiki.extension.job.internal.InstallJob.start(InstallJob.java:118)
    at org.xwiki.job.AbstractJob.start(AbstractJob.java:134)
    at org.xwiki.job.internal.DefaultJobManager.run(DefaultJobManager.java:155)
    at java.lang.Thread.run(Thread.java:722)
Caused by: class java.net.ConnectException: Connection refused: connect
    at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
    at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:75)
    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:339)
    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:200)
    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:182)
    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:157)
    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:391)
    at java.net.Socket.connect(Socket.java:579)
    at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:127)
    at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:180)
    at org.apache.http.impl.conn.ManagedClientConnectionImpl.open(ManagedClientConnectionImpl.java:294)
    at org.apache.http.impl.client.DefaultRequestDirector.tryConnect(DefaultRequestDirector.java:640)
    at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:479)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:906)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:805)
    at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:784)
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionRepository.getRESTResource(XWikiExtensionRepository.java:123)
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionRepository.getRESTResourceAsStream(XWikiExtensionRepository.java:138)
    at org.xwiki.extension.repository.xwiki.internal.XWikiExtensionFile.openStream(XWikiExtensionFile.java:76)
    at org.xwiki.extension.repository.internal.local.DefaultLocalExtensionRepository.storeExtension(DefaultLocalExtensionRepository.java:159)
    at org.xwiki.extension.job.internal.InstallJob.storeExtension(InstallJob.java:157)
    at org.xwiki.extension.job.internal.InstallJob.store(InstallJob.java:145)
    at org.xwiki.extension.job.internal.InstallJob.start(InstallJob.java:118)
    at org.xwiki.job.AbstractJob.start(AbstractJob.java:134)
    at org.xwiki.job.internal.DefaultJobManager.run(DefaultJobManager.java:155)
    at java.lang.Thread.run(Thread.java:722)