code: public static ISREInstall getDefaultSREInstall() {
  		final ISREInstall install = getSREFromId(getDefaultSREId());
  		if (install != null && install.getValidity().isOK()) {
  			return install;
  		}
  		// if the default SRE goes missing, re-detect
  		LOCK.lock();
  		try {
  			//defaultSREId = null;
  			initializeSREs();
  		} finally {
  			LOCK.unlock();
  		}
  		return getSREFromId(getDefaultSREId());
  	}
docs: Return the default SRE set with <code>setDefaultSRE()</code>.
  
  @return	Returns the default SRE. May return <code>null</code> when no default
  SRE was set or when the default SRE has been disposed.