private void initComponents() {
		// JFormDesigner - Component initialization - DO NOT MODIFY  //GEN-BEGIN:initComponents
		panel = new JPanel();
		filterPanel = new JPanel();
		filterLabel = new JLabel();
		filterField = new FlatTextField();
		valueTypeLabel = new JLabel();
		valueTypeField = new JComboBox<>();
		scrollPane = new JScrollPane();
		table = new JTable();
		tablePopupMenu = new JPopupMenu();
		copyKeyMenuItem = new JMenuItem();
		copyValueMenuItem = new JMenuItem();
		copyKeyAndValueMenuItem = new JMenuItem();

		//======== panel ========
		{
			panel.setLayout(new BorderLayout());

			//======== filterPanel ========
			{
				filterPanel.setLayout(new GridBagLayout());
				((GridBagLayout)filterPanel.getLayout()).columnWidths = new int[] {0, 0, 0, 0, 0};
				((GridBagLayout)filterPanel.getLayout()).rowHeights = new int[] {0, 0};
				((GridBagLayout)filterPanel.getLayout()).columnWeights = new double[] {0.0, 1.0, 0.0, 0.0, 1.0E-4};
				((GridBagLayout)filterPanel.getLayout()).rowWeights = new double[] {0.0, 1.0E-4};

				//---- filterLabel ----
				filterLabel.setText("Filter:");
				filterLabel.setLabelFor(filterField);
				filterLabel.setDisplayedMnemonic('F');
				filterPanel.add(filterLabel, new GridBagConstraints(0, 0, 1, 1, 0.0, 0.0,
					GridBagConstraints.CENTER, GridBagConstraints.BOTH,
					new Insets(0, 0, 0, 10), 0, 0));

				//---- filterField ----
				filterField.setPlaceholderText("enter one or more filter strings, separated by space characters");
				filterField.setShowClearButton(true);
				filterPanel.add(filterField, new GridBagConstraints(1, 0, 1, 1, 0.0, 0.0,
					GridBagConstraints.CENTER, GridBagConstraints.BOTH,
					new Insets(0, 0, 0, 10), 0, 0));

				//---- valueTypeLabel ----
				valueTypeLabel.setText("Value Type:");
				valueTypeLabel.setLabelFor(valueTypeField);
				valueTypeLabel.setDisplayedMnemonic('T');
				filterPanel.add(valueTypeLabel, new GridBagConstraints(2, 0, 1, 1, 0.0, 0.0,
					GridBagConstraints.CENTER, GridBagConstraints.BOTH,
					new Insets(0, 0, 0, 10), 0, 0));

				//---- valueTypeField ----
				valueTypeField.setModel(new DefaultComboBoxModel<>(new String[] {
					"(any)",
					"Boolean",
					"Border",
					"Color",
					"Color (\u03b1)",
					"Color (\u0192)",
					"Dimension",
					"Float",
					"Font",
					"Icon",
					"Insets",
					"Integer",
					"String",
					"(other)"
				}));
				valueTypeField.addActionListener(e -> filterChanged());
				filterPanel.add(valueTypeField, new GridBagConstraints(3, 0, 1, 1, 0.0, 0.0,
					GridBagConstraints.CENTER, GridBagConstraints.BOTH,
					new Insets(0, 0, 0, 0), 0, 0));
			}
			panel.add(filterPanel, BorderLayout.NORTH);

			//======== scrollPane ========
			{

				//---- table ----
				table.setAutoCreateRowSorter(true);
				table.setComponentPopupMenu(tablePopupMenu);
				table.addMouseListener(new MouseAdapter() {
					@Override
					public void mousePressed(MouseEvent e) {
						tableMousePressed(e);
					}
				});
				scrollPane.setViewportView(table);
			}
			panel.add(scrollPane, BorderLayout.CENTER);
		}

		//======== tablePopupMenu ========
		{

			//---- copyKeyMenuItem ----
			copyKeyMenuItem.setText("Copy Key");
			copyKeyMenuItem.addActionListener(e -> copyKey());
			tablePopupMenu.add(copyKeyMenuItem);

			//---- copyValueMenuItem ----
			copyValueMenuItem.setText("Copy Value");
			copyValueMenuItem.addActionListener(e -> copyValue());
			tablePopupMenu.add(copyValueMenuItem);

			//---- copyKeyAndValueMenuItem ----
			copyKeyAndValueMenuItem.setText("Copy Key and Value");
			copyKeyAndValueMenuItem.addActionListener(e -> copyKeyAndValue());
			tablePopupMenu.add(copyKeyAndValueMenuItem);
		}
		// JFormDesigner - End of component initialization  //GEN-END:initComponents
	}
Creates a UI defaults inspector panel that can be embedded into any window.
flatlaf-extras/src/main/java/com/formdev/flatlaf/extras/FlatUIDefaultsInspector.java