Apply a Builder design pattern:
The Client GUI is constructed using many Jcomponents groups, it uses various Jpanels and each Jpanel contains more Jcomponents. All this is only created in one class, the ClientGUI, with the builder pattern we can separate this complex object into smaller ones and use a step by step approach to construct the client GUI. To implement this design pattern, we can use the extract class code refactoring and can help to eliminate the long class code smell.
The WestPanel, CenterPanel and NorthPanel classes will be created to buil the client gui. The ClientGUI class that already exists will work as the clinet gui builder class.
Code changes applied