title: Tycho cannot download from official p2 repository
body: <p>I have a Eclipse E4 application that is already build by Tycho. Now we are migrating the application to use Java 12. Herefore we also need to update our target file.</p>
  
  <p>The latest target file looks like:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8" standalone="no"?&gt;
  &lt;?pde version="3.8"?&gt;
  &lt;target includeMode="feature" name="Running Platform"&gt;
      &lt;locations&gt;
          &lt;location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit"&gt;
              &lt;repository location="http://download.eclipse.org/nattable/releases/1.5.0/repository/"/&gt;
              &lt;unit id="org.eclipse.nebula.widgets.nattable.core.feature.feature.group" version="1.5.0.201703192131"/&gt;
              &lt;unit id="org.eclipse.nebula.widgets.nattable.extension.e4.feature.feature.group" version="1.1.0.201703192131"/&gt;
              &lt;unit id="org.eclipse.nebula.widgets.nattable.extension.glazedlists.feature.feature.group" version="1.5.0.201703192131"/&gt;
              &lt;unit id="org.eclipse.nebula.widgets.nattable.extension.nebula.feature.feature.group" version="1.1.0.201703192131"/&gt;
              &lt;unit id="org.eclipse.nebula.widgets.nattable.extension.poi.feature.feature.group" version="1.5.0.201703192131"/&gt;
          &lt;/location&gt;
          &lt;location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit"&gt;
              &lt;repository location="http://download.eclipse.org/releases/2019-06/"/&gt;
              &lt;unit id="org.eclipse.equinox.sdk.feature.group" version="3.18.0.v20190528-1257"/&gt;
              &lt;unit id="org.eclipse.platform.sdk" version="4.12.0.I20190605-1800"/&gt;
          &lt;/location&gt;
          &lt;location includeAllPlatforms="false" includeConfigurePhase="true" includeMode="planner" includeSource="true" type="InstallableUnit"&gt;
              &lt;repository location="http://download.eclipse.org/nebula/releases/latest"/&gt;
              &lt;unit id="org.eclipse.nebula.widgets.pshelf.css.feature.feature.group" version="1.0.0.201812241324"/&gt;
              &lt;unit id="org.eclipse.nebula.widgets.pshelf.feature.feature.group" version="1.0.0.201812241324"/&gt;
          &lt;/location&gt;
      &lt;/locations&gt;
      &lt;environment&gt;
          &lt;arch&gt;x86_64&lt;/arch&gt;
          &lt;os&gt;win32&lt;/os&gt;
          &lt;ws&gt;win32&lt;/ws&gt;
          &lt;nl&gt;en_US&lt;/nl&gt;
      &lt;/environment&gt;
  &lt;/target&gt;
  </code></pre>
  
  <p>When we run the build with tycho using Jenkins we are getting following error:</p>
  
  <pre><code>[INFO] Fetching p2.index from http://download.eclipse.org/nattable/releases/1.5.0/repository/
  
  [INFO] Fetching p2.index from http://download.eclipse.org/nattable/releases/1.5.0/repository/
  
  [INFO] Adding repository http://download.eclipse.org/nattable/releases/1.5.0/repository
  
  [INFO] Fetching p2.index from http://download.eclipse.org/releases/2019-06/
  
  [INFO] Fetching p2.index from http://download.eclipse.org/releases/2019-06/
  
  [INFO] Adding repository http://download.eclipse.org/releases/2019-06
  
  WARNING: An illegal reflective access operation has occurred
  
  WARNING: Illegal reflective access by org.eclipse.ecf.provider.filetransfer.httpclient4.SNIAwareHttpClient$1 (file:/C:/Users/PTITDevTools_svc/.m2/repository/org/eclipse/tycho/tycho-bundles-external/1.1.0/eclipse/plugins/org.eclipse.ecf.provider.filetransfer.httpclient4_1.1.200.v20170314-0133.jar) to method sun.security.ssl.SSLSocketImpl.setHost(java.lang.String)
  
  WARNING: Please consider reporting this to the maintainers of org.eclipse.ecf.provider.filetransfer.httpclient4.SNIAwareHttpClient$1
  
  WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
  
  WARNING: All illegal access operations will be denied in a future release
  
  [ERROR] Failed to resolve target definition D:\Software\x64\Jenkins\workspace\ture_ILMV-490-migrate-to-java-12\neon\neon.target: Failed to load p2 metadata repository from location http://download.eclipse.org/releases/2019-06/: Unable to read repository at http://download.eclipse.org/releases/2019-06. Unable to read repository at https://download.eclipse.org/technology/epp/packages/2019-06/content.xml. Connection reset -&gt; [Help 1]
  </code></pre>
  
  <p>With our <a href="https://www.codepile.net/pile/xO8oR272" rel="nofollow noreferrer">old Target file</a> the build was working but the old file was a PDE target file. Can someone tell me why this is failing?</p>