private static String getEclipseHomeLocation(String launcher) {
if (launcher == null) return null;
File launcherFile = new File(launcher);
if (launcherFile.getParent() == null) return null;
File launcherDir = new File(launcherFile.getParent());
// check for mac os; the os check is copied from EclipseEnvironmentInfo.
String macosx = org.eclipse.osgi.service.environment.Constants.OS_MACOSX;
if (macosx.equals(EclipseEnvironmentInfo.getDefault().getOS()))
launcherDir = getMacOSEclipsoeHomeLocation(launcherDir);
return (launcherDir.exists() && launcherDir.isDirectory())
? launcherDir.getAbsolutePath()
: null;
}
