Somehow, the jbosstools-hibernate build is trying to download stuff from the /oxygen/staging/updates/core/4.5.3.AM2 site.
It should NOT be sourcing a site that contains hibernate plugins (and stuff downstream from hibernate) as this could cause an inadvertent circular dependency.
16:46:48 [ERROR] Failed to execute goal org.eclipse.tycho:tycho-p2-plugin:1.1.0:p2-metadata (attached-p2-metadata) on project org.jboss.tools.hibernate.runtime.v_4_3: Execution attached-p2-metadata of goal org.eclipse.tycho:tycho-p2-plugin:1.1.0:p2-metadata failed: Error trying to download org.jboss.tools.hibernate.runtime.v_4_3 version 5.2.3.v20180203-1505 from http://download.jboss.org/jbosstools/oxygen/staging/updates/core/4.5.3.AM2: 16:46:48 [ERROR] Download of osgi.bundle,org.jboss.tools.hibernate.runtime.v_4_3,5.2.3.v20180203-1505 failed on repository http://download.jboss.org/jbosstools/oxygen/staging/updates/core/4.5.3.AM2. Retrying. : 16:46:48 [ERROR] Unable to read repository at http://download.jboss.org/jbosstools/oxygen/staging/updates/core/4.5.3.AM2/plugins/org.jboss.tools.hibernate.runtime.v_4_3_5.2.3.v20180203-1505.jar.pack.gz. Premature end of Content-Length delimited message body (expected: 6775721; received: 5831379 16:46:48 [ERROR] -> [Help 1] 16:46:48 org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.eclipse.tycho:tycho-p2-plugin:1.1.0:p2-metadata (attached-p2-metadata) on project org.jboss.tools.hibernate.runtime.v_4_3: Execution attached-p2-metadata of goal org.eclipse.tycho:tycho-p2-plugin:1.1.0:p2-metadata failed: Error trying to download org.jboss.tools.hibernate.runtime.v_4_3 version 5.2.3.v20180203-1505 from http://download.jboss.org/jbosstools/oxygen/staging/updates/core/4.5.3.AM2: 16:46:48 Download of osgi.bundle,org.jboss.tools.hibernate.runtime.v_4_3,5.2.3.v20180203-1505 failed on repository http://download.jboss.org/jbosstools/oxygen/staging/updates/core/4.5.3.AM2. Retrying. : 16:46:48 Unable to read repository at http://download.jboss.org/jbosstools/oxygen/staging/updates/core/4.5.3.AM2/plugins/org.jboss.tools.hibernate.runtime.v_4_3_5.2.3.v20180203-1505.jar.pack.gz.