Eclipse Mars (4.5) Built-in workspace

I recently updated to Eclipse Mars (4.5) from Eclipse Luna (4.4). After importing the Gradle project, Eclipse Mars will get stuck when trying to create a workspace.

I have one Gradle project which contains three sub-projects. Importing this project into Eclipse will create four projects (ie, the Root Project and three Subprojects). This is a non-trivial project. If anyone is interested, here is a link to the project on GitHub.

I've highlighted the issue in this JUnit XmlParserTest.java test file .

For some reason, the following code will make Eclipse Mars get stuck while creating a workspace.

assertThat(organization.getAchieves(r1).stream().map(SpecificationGoal::getId)
    .collect(Collectors.toCollection(HashSet::new)), hasItem(g1));

      

        
        
        
      

    

If I comment out all of the similar code in XmlParserTest.java

Eclipse Mars completes the creation of the workspace. Eclipse Luna doesn't have this problem.

I am focused on the cause of this problem. Any help I can solve on this issue is greatly appreciated.