Unable to install new Eclipse Helios software - eclipse

Question

I have a problem downloading new software via the "Install New Software..." dialog of Eclipse Helios.
It used to work a few weeks ago, but now I get the following error when I try to visit the official Helios site.
org.eclipse.equinox.p2.core.ProvisionException
Unable to read repository at http://download.eclipse.org/releases/helios.
This is what I get in the error log:
eclipse.buildId=M20110210-1200
java.version=1.6.0_20
java.vendor=Sun Microsystems Inc.
BootLoader constants: OS=linux, ARCH=x86, WS=gtk, NL=en_DK
Framework arguments: -product org.eclipse.epp.package.java.product
Command-line arguments: -os linux -ws gtk -arch x86 -product org.eclipse.epp.package.java.product
Error
Thu Apr 21 12:56:41 CEST 2011
Unable to read repository at http://download.eclipse.org/releases/helios.
org.eclipse.equinox.p2.core.ProvisionException: Unable to read repository at http://download.eclipse.org/releases/helios.
at org.eclipse.equinox.internal.p2.metadata.repository.CompositeMetadataRepositoryFactory.load(CompositeMetadataRepositoryFactory.java:137)
at org.eclipse.equinox.internal.p2.metadata.repository.MetadataRepositoryManager.factoryLoad(MetadataRepositoryManager.java:57)
at org.eclipse.equinox.internal.p2.repository.helpers.AbstractRepositoryManager.loadRepository(AbstractRepositoryManager.java:746)
at org.eclipse.equinox.internal.p2.repository.helpers.AbstractRepositoryManager.loadRepository(AbstractRepositoryManager.java:651)
at org.eclipse.equinox.internal.p2.metadata.repository.MetadataRepositoryManager.loadRepository(MetadataRepositoryManager.java:96)
at org.eclipse.equinox.internal.p2.metadata.repository.MetadataRepositoryManager.loadRepository(MetadataRepositoryManager.java:92)
at org.eclipse.equinox.p2.ui.ProvisioningUI.loadMetadataRepository(ProvisioningUI.java:388)
at org.eclipse.equinox.internal.p2.ui.model.MetadataRepositoryElement.getMetadataRepository(MetadataRepositoryElement.java:120)
at org.eclipse.equinox.internal.p2.ui.model.MetadataRepositoryElement.getRepository(MetadataRepositoryElement.java:109)
at org.eclipse.equinox.internal.p2.ui.model.MetadataRepositoryElement.getQueryable(MetadataRepositoryElement.java:103)
at org.eclipse.equinox.internal.p2.ui.QueryProvider.getQueryDescriptor(QueryProvider.java:54)
at org.eclipse.equinox.internal.p2.ui.model.QueriedElement.fetchChildren(QueriedElement.java:102)
at org.eclipse.equinox.internal.p2.ui.model.MetadataRepositoryElement.fetchChildren(MetadataRepositoryElement.java:72)
at org.eclipse.equinox.internal.p2.ui.model.RemoteQueriedElement.fetchDeferredChildren(RemoteQueriedElement.java:34)
at org.eclipse.ui.progress.DeferredTreeContentManager$1.run(DeferredTreeContentManager.java:235)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:54)
Caused by: java.io.IOException: http://download.eclipse.org/releases/helios is not a valid repository location.
at org.eclipse.equinox.internal.p2.metadata.repository.CompositeMetadataRepositoryFactory.load(CompositeMetadataRepositoryFactory.java:113)
... 15 more
I have used wireshark to see exactly what eclipse does when I request the update site, and I have discovered that it does a HTTP GET request on the host download.eclipse.org, for the page "/releases/helios/p2.index" (without quotes) and that it gets a 404 error from the webserver.
This is what I get when I navigate to http://download.eclipse.org/releases/helios/p2.index as well.
Does anyone have the same problem? Do I have something in my settings mixed up? Does anyone have an idea to solve my problem? or do you guys need some more info?

Answer 1

The bug 341665 presents a similar case and has the workaround of using a mirror:
I found where the problem is. I'm here in China, and I can't access
http://www.gtlib.gatech.edu/pub/eclipse/releases/helios/, where http://download.eclipse.org/releases/helios/compositeContent.jar is redirected to, because our government has blocked the access to http://www.gtlib.gatech.edu/*
So please change a repository to help us developers in China. Thank you.
[reply] [-] Comment 5 shining366#gmail.com 2011-04-15 20:47:08 EDT
I find a workaround:
use http://mirror.neu.edu.cn/eclipse/releases/helios/ instead of http://download.eclipse.org/releases/helios
Note, as described in bug 325299:
There is an ordering for the files that we look for when we connect to a server:
compositeContent.jar
compositeContent.xml
content.jar
content.xml
site.xml

Answer 2

add this line to
eclipse.ini
-Djava.net.preferIPv4Stack=true