在Eclipse Neon中安装Saros“收集要安装的项目时出错”

Question

I'm trying to install Saros ( http://www.saros-project.org/ ) in Eclipse Neon but have repeatedly received the following error details:

An error occurred while collecting items to be installed
session context was:(profile=epp.package.jee, phase=org.eclipse.equinox.internal.p2.engine.phases.Collect, operand=, action=).
Unable to read repository at http://downloads.sourceforge.net/dpp/de.fu_berlin.inf.dpp_14.10.31.jar?use_mirror=dfn.
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
Unable to read repository at http://downloads.sourceforge.net/dpp/de.fu_berlin.inf.dpp.core_0.1.0.jar?use_mirror=dfn.
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
Unable to read repository at http://downloads.sourceforge.net/dpp/de.fu_berlin.inf.dpp.whiteboard_14.10.31.jar?use_mirror=dfn.
sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

I've tried all of the solutions I can find, all of which appear to be collectively posted on this page: What to do about Eclipse's "No repository found containing: ..." error messages? but nothing appears to change.

My computer is running MacOS Sierra and my version of Eclipse is Eclipse Java EE IDE for Web Developers Version: Neon.2 Release (4.6.2)

Any other recommendations for what I could try next?

Thank you!

Answer 1

In December 2016, Sourceforge introduced automatic forwarding to HTTPS servers (even if the URLs are entered with HTTP) which used "Let's Encrypt" certificates. Older Java versions (below Java 8u101 and Java 7u111) did not recognize "Let's Encrypt"'s root certificate and this results in said error message (no "valid certification path").

But: As of now, Sourceforge seems to have switched to "GeoTrust" certificates, which should pose no problem, even for older Java versions.

So the first thing to check : Try to install Saros again. Do you still get certificate errors?

If the problem persists from some reason, you have two options:

1. Easy way: Install Saros not from the update site, but as a dropin instead of using the update site. There is a How-To on the project website: Instructions for installing Saros as a dropin

2. Uncertain way: You could try to find out which certificate authority (CA) issued the certificates used by the HTTPS server you get forwarded to. (Eg type one of the HTTP URLs from the error message into your web browser, wait until you get redirected to an HTTPS URL, and check the certificate information -- usually a green lock icon next to your address bar.) If you have the CA's name, there might be website explaining how to add its root certificate to your Java setup (similar to this one , which gives some hints for the "Let's Encrypt" case).

Update (2017-03-31):

I heard from others that the problem with Sourceforge still persists for them. As an alternative to installing Saros as a dropin (option 1 above), you can also use our secondary Eclipse update site which is hosted on Heroku: https://get-saros.herokuapp.com/eclipse