Bug 29698 drag and drop of java files between packages in package explorer doesn't work
the <preview> <ok> <cancel> dialog shows up, but <ok> has the same effect as <cancel> and <preview> would only show movements of files and no changes in imports of other java files. on <ok> in the preview it only moves the file(s) (as indicated ) without changing referencing imports.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/refactoring/RenameSupport.java
public static RenameSupport create(IJavaElement element, String newName, int flags) throws CoreException {
		switch (element.getElementType()) {
			case IJavaElement.JAVA_PROJECT:
				return create((IJavaProject)element, newName, flags); 
			case IJavaElement.PACKAGE_FRAGMENT_ROOT:
				return create((IPackageFragmentRoot)element, newName); 
			case IJavaElement.PACKAGE_FRAGMENT:
				return create((IPackageFragment)element, newName, flags); 
			case IJavaElement.COMPILATION_UNIT:
				return create((ICompilationUnit)element, newName, flags); 
			case IJavaElement.TYPE:
				return create((IType)element, newName, flags); 
			case IJavaElement.METHOD:
				return create((IMethod)element, newName, flags); 
			case IJavaElement.FIELD:
				return create((IField)element, newName, flags); 
		}
		return null;
	}
	
	private static void setNewName(IRenameRefactoring refactoring, String newName) {
		if (newName != null)
			refactoring.setNewName(newName);
	}
	
	private static boolean updateReferences(int flags) {
		return (flags & UPDATE_REFERENCES) != 0;
	}
	
	private static boolean updateJavadocComments(int flags) {