+import jalview.datamodel.Alignment;
+import jalview.datamodel.AlignmentView;
+import jalview.datamodel.ColumnSelection;
+import jalview.datamodel.SeqCigar;
+import jalview.datamodel.SequenceI;
+import jalview.jbgui.GPCAPanel;
+import jalview.schemes.ResidueProperties;
+import jalview.util.MessageManager;
+import jalview.viewmodel.AlignmentViewport;
+import jalview.viewmodel.PCAModel;
+
+import java.awt.BorderLayout;
+import java.awt.Color;
+import java.awt.Graphics;
+import java.awt.GridLayout;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.awt.print.PageFormat;
+import java.awt.print.Printable;
+import java.awt.print.PrinterException;
+import java.awt.print.PrinterJob;
+import java.util.Hashtable;
+
+import javax.swing.ButtonGroup;
+import javax.swing.JButton;
+import javax.swing.JCheckBoxMenuItem;
+import javax.swing.JColorChooser;
+import javax.swing.JLabel;
+import javax.swing.JMenuItem;
+import javax.swing.JOptionPane;
+import javax.swing.JPanel;
+import javax.swing.JProgressBar;
+import javax.swing.JRadioButtonMenuItem;