Sometimes using SpringSource Tool Suite (STS) e.g. version 2.3.2- which is based on Eclipse – startup hangs on various operations:

Initializing Java Tooling

Repository registry initialization

STS/Eclipse does not seem to respond to anything – the UI freezes and that’s it! I’ve had this on several occassions with no apparent cause on my part. Usually it has something to do with fiddling with (adding libraries to) the classpath and/or cleaning the project. Some users report Eclipse hangs at “Initializing Java Tooling” at 30% for 20-30 secs after which everything continues normally, but I don’t have that much luck 🙂

I’ve tried the most suggested actions in forum posts, such a starting STS/Eclipse with the -clean parameter which most of the times doesn’t work in my configuration. If you inspect the .log files under the workspace’s .metadata folder you might find something of interest, but quite often STS/Eclipse just hangs without anything written to the log in my case. The largeness of your project or the amount of projects quite often seem to be one of the causes. Here are a few workarounds and/or solutions that might prove succesful:

  • Start a new workspace and import the project back in – which is just plain tedious and annoying although it quite often works
  • Close all projects before you exit Eclipse after which Eclipse normally restarts.
  • Some users have reported it does seem related to a configured Tomcat server instance. If you have this configured a possible workaround instead of reimporting your projects in a new workspace, is to rename the .project file in workspace/Servers, restarting, removing and adding the Server configuration again.
  • The solution I found – which seems to work most of the times – is to remove or rename the .projects folder in .metadata/.plugins/org.eclipse.core.resources in the workspace folder. This doesn’t seem to affect any project and the .project folder will be recreated when Eclipse restarts.

Hopefully someone with this problem saves some time because of this. Ofcourse the real problem needs to be addressed by the guys and girls over at Eclipse.