Fix some of the SonarQube issues

Author: Eswcvlad

src/main/java/com/itextpdf/rups/controller/PdfReaderController.java

@@ -79,6 +79,8 @@ This file is part of the iText (R) project.
 
 import java.awt.Color;
 import java.awt.event.KeyListener;
+import java.util.ArrayDeque;
+import java.util.Deque;
 import java.util.Stack;
 import java.util.function.Consumer;
 import javax.swing.JPanel;
@@ -145,7 +147,7 @@ public class PdfReaderController implements IPdfObjectPanelEventListener, IRupsE
      */
     protected PlainText text;
 
-    private final Stack<IconTreeNode> highlights = new Stack<>();
+    private final Deque<IconTreeNode> highlights = new ArrayDeque<>();
 
     private final PdfSyntaxParser parser = new PdfSyntaxParser();
 
@@ -359,7 +361,7 @@ protected void highlightChanges(CompareTool.CompareResult compareResult) {
     }
 
     protected void clearHighlights() {
-        while (!highlights.empty()) {
+        while (!highlights.isEmpty()) {
             highlights.pop().restoreDefaultTextColor();
         }
     }

src/main/java/com/itextpdf/rups/view/Console.java

@@ -63,7 +63,7 @@ This file is part of the iText (R) project.
 /**
  * A Class that is used for displaying logger messages to a {@link JTextPane}.
  */
-public class Console implements IRupsEventListener {
+public final class Console implements IRupsEventListener {
 
     /**
      * Single Console instance.

src/main/java/com/itextpdf/rups/view/RupsMenuBar.java

@@ -65,10 +65,6 @@ This file is part of the iText (R) project.
 
 public final class RupsMenuBar extends JMenuBar implements IRupsEventListener {
     private final IRupsController controller;
-    /**
-     * The action needed to open a file.
-     */
-    private final PdfFileOpenAction fileOpenAction;
     /**
      * The Preferences Window
      */
@@ -87,13 +83,11 @@ public RupsMenuBar(RupsController controller) {
 
         preferencesWindow = new PreferencesWindow();
 
-        fileOpenAction = new PdfFileOpenAction(controller::openNewFile, controller.getMasterComponent());
-
         final JMenu file = new JMenu(Language.MENU_BAR_FILE.getString());
         addItem(
                 file,
                 Language.MENU_BAR_OPEN,
-                fileOpenAction,
+                new PdfFileOpenAction(controller::openNewFile, controller.getMasterComponent()),
                 KeyStroke.getKeyStroke('O', InputEvent.CTRL_DOWN_MASK)
         );
         file.add(createOpenRecentSubMenu());

src/main/java/com/itextpdf/rups/view/itext/CloseableTabComponent.java

@@ -67,6 +67,8 @@ This file is part of the iText (R) project.
  * </p>
  */
 public final class CloseableTabComponent extends JPanel {
+    private static final int SEPARATOR_WIDTH = 8;
+
     private final List<IntConsumer> closeButtonListeners = new ArrayList<>();
 
     public CloseableTabComponent(JTabbedPane parent) {
@@ -88,7 +90,7 @@ public String getText() {
 
         final JButton button = new CloseButton();
         button.addActionListener((ActionEvent e) -> {
-            final int idx = parent.indexOfTabComponent(CloseableTabComponent.this);
+            final int idx = parent.indexOfTabComponent(this);
             if (idx >= 0) {
                 for (final IntConsumer listener : closeButtonListeners) {
                     listener.accept(idx);
@@ -97,7 +99,7 @@ public String getText() {
         });
 
         add(label);
-        add(Box.createHorizontalStrut(8));
+        add(Box.createHorizontalStrut(SEPARATOR_WIDTH));
         add(button);
     }
 

src/main/java/com/itextpdf/rups/view/itext/FormTree.java

@@ -75,20 +75,16 @@ public final class FormTree extends JTree implements TreeSelectionListener, IRup
     /**
      * Nodes in the FormTree correspond with nodes in the main PdfTree.
      */
-    private PdfReaderController controller;
+    private final PdfReaderController controller;
 
-    /**
-     * If the form is an XFA form, the XML file is stored in this object.
-     */
-    private XfaFile xfaFile;
     /**
      * Treeview of the XFA file.
      */
-    private XfaTree xfaTree;
+    private final XfaTree xfaTree;
     /**
      * Textview of the XFA file.
      */
-    private XfaTextArea xfaTextArea;
+    private final XfaTextArea xfaTextArea;
 
     /**
      * Creates a new FormTree.
@@ -193,7 +189,6 @@ void loadXfa(TreeNodeFactory factory, XfaTreeNode form_node, PdfObjectTreeNode o
 
     @Override
     public void handleCloseDocument() {
-        xfaFile = null;
         xfaTree.clear();
         xfaTextArea.clear();
         setModel(new DefaultTreeModel(new FormTreeNode()));
@@ -223,7 +218,7 @@ public void handleOpenDocument(ObjectLoader loader) {
             loadXfa(factory, node, xfa);
             root.add(node);
             try {
-                xfaFile = new XfaFile(node);
+                final XfaFile xfaFile = new XfaFile(node);
                 xfaTree.load(xfaFile);
                 xfaTextArea.load(xfaFile);
             } catch (IOException e) {

src/main/java/com/itextpdf/rups/view/itext/OutlineTree.java

@@ -66,7 +66,7 @@ public final class OutlineTree extends JTree implements TreeSelectionListener, I
     /**
      * Nodes in the FormTree correspond with nodes in the main PdfTree.
      */
-    private PdfReaderController controller;
+    private final PdfReaderController controller;
 
     /**
      * Creates a new outline tree.

src/main/java/com/itextpdf/rups/view/itext/PdfObjectPanel.java

@@ -79,16 +79,6 @@ public final class PdfObjectPanel implements IRupsEventListener {
     private static final String ADD_ICON = "add.png";
     private static final String CROSS_ICON = "cross.png";
 
-    /**
-     * Name of a panel in the CardLayout.
-     */
-    private static final String TABLE = Language.TABLE.getString();
-
-    /**
-     * Name of a panel in the CardLayout.
-     */
-    private static final String TEXT = Language.TEXT.getString();
-
     /**
      * The layout that will show the info about the PDF object that is being analyzed.
      */
@@ -122,13 +112,13 @@ public PdfObjectPanel() {
         // dictionary / array / stream
         final JScrollPane dictScrollPane = new JScrollPane();
         dictScrollPane.setViewportView(table);
-        panel.add(dictScrollPane, TABLE);
+        panel.add(dictScrollPane);
 
         // number / string / ...
         final JScrollPane textScrollPane = new JScrollPane();
         textScrollPane.setViewportView(text);
         text.setEditable(false);
-        panel.add(textScrollPane, TEXT);
+        panel.add(textScrollPane);
 
         table.addMouseListener(new JTableButtonMouseListener());
     }
@@ -144,7 +134,7 @@ public void clear() {
         target = null;
         table.setModel(new DefaultTableModel());
         text.setText(null);
-        layout.show(panel, TEXT);
+        layout.show(panel, Language.TEXT.getString());
     }
 
     @Override
@@ -190,7 +180,7 @@ public void render(PdfObjectTreeNode node, PdfSyntaxParser parser) {
         if (object == null) {
             text.setText(null);
             table.setModel(new DefaultTableModel());
-            layout.show(panel, TEXT);
+            layout.show(panel, Language.TEXT.getString());
             panel.repaint();
             text.repaint();
             return;
@@ -208,7 +198,7 @@ public void render(PdfObjectTreeNode node, PdfSyntaxParser parser) {
                         DictionaryTableModelButton.class,
                         new DictionaryTableModelButton(IconFetcher.getIcon(CROSS_ICON), IconFetcher.getIcon(ADD_ICON))
                 );
-                layout.show(panel, TABLE);
+                layout.show(panel, Language.TABLE.getString());
                 panel.repaint();
                 break;
             case PdfObject.ARRAY:
@@ -221,16 +211,16 @@ public void render(PdfObjectTreeNode node, PdfSyntaxParser parser) {
                         DictionaryTableModelButton.class,
                         new DictionaryTableModelButton(IconFetcher.getIcon(CROSS_ICON), IconFetcher.getIcon(ADD_ICON))
                 );
-                layout.show(panel, TABLE);
+                layout.show(panel, Language.TABLE.getString());
                 panel.repaint();
                 break;
             case PdfObject.STRING:
                 text.setText(((PdfString) object).toUnicodeString());
-                layout.show(panel, TEXT);
+                layout.show(panel, Language.TEXT.getString());
                 break;
             default:
                 text.setText(object.toString());
-                layout.show(panel, TEXT);
+                layout.show(panel, Language.TEXT.getString());
                 break;
         }
     }
@@ -243,6 +233,12 @@ private AbstractPdfObjectPanelTableModel getTableModel() {
         return null;
     }
 
+    private void fireEvent(Consumer<IPdfObjectPanelEventListener> func) {
+        for (final IPdfObjectPanelEventListener listener: eventListeners) {
+            func.accept(listener);
+        }
+    }
+
     private class JTableButtonMouseListener extends MouseAdapter {
         public void mouseClicked(MouseEvent e) {
             final int selectedColumn = table.getSelectedColumn();
@@ -314,10 +310,4 @@ public void tableChanged(TableModelEvent e) {
             }
         }
     }
-
-    private void fireEvent(Consumer<IPdfObjectPanelEventListener> func) {
-        for (final IPdfObjectPanelEventListener listener: eventListeners) {
-            func.accept(listener);
-        }
-    }
 }

src/main/java/com/itextpdf/rups/view/itext/PlainText.java

@@ -55,9 +55,13 @@ public final class PlainText extends ReadOnlyTextArea implements IRupsEventListe
 
     private boolean loaded = false;
 
-    private IPdfFile file;
+    private IPdfFile file = null;
 
-    private SwingWorker<String, Object> worker;
+    private SwingWorker<String, Object> worker = null;
+
+    public PlainText() {
+        // Empty
+    }
 
     public void openPlainText() {
         if (file == null || loaded) {

src/main/java/com/itextpdf/rups/view/itext/StructureTree.java

@@ -85,7 +85,7 @@ public final class StructureTree extends JTree implements TreeSelectionListener,
     /**
      * Nodes in the FormTree correspond with nodes in the main PdfTree.
      */
-    private PdfReaderController controller;
+    private final PdfReaderController controller;
 
     private ObjectLoader loader;
 

src/main/java/com/itextpdf/rups/view/itext/SyntaxHighlightedStreamPane.java

@@ -97,11 +97,11 @@ public final class SyntaxHighlightedStreamPane extends JScrollPane implements IR
      */
     private final JSyntaxPane text;
 
-    private StreamPanelContextMenu popupMenu;
+    private final StreamPanelContextMenu popupMenu;
 
     private PdfObjectTreeNode target;
 
-    private UndoManager manager;
+    private final UndoManager manager;
 
     //Todo: Remove that field after proper application structure will be implemented.
     private final PdfReaderController controller;