Made sure to properly install/uninstall listeners to avoid NPEs when switching look and feels.

src/com/bulenkov/darcula/ui/DarculaPasswordFieldUI.java

@@ -25,29 +25,42 @@ import javax.swing.text.JTextComponent;
 import java.awt.*;
 import java.awt.event.FocusAdapter;
 import java.awt.event.FocusEvent;
+import java.awt.event.FocusListener;
 
 /**
  * @author Konstantin Bulenkov
  */
 public class DarculaPasswordFieldUI extends BasicPasswordFieldUI {
 
-  @SuppressWarnings({"MethodOverridesStaticMethodOfSuperclass", "UnusedDeclaration"})
+  private FocusListener myFocusListener = new FocusAdapter() {
-  public static ComponentUI createUI(final JComponent c) {
-    c.addFocusListener(new FocusAdapter() {
     @Override
     public void focusGained(FocusEvent e) {
-        c.repaint();
+      getComponent().repaint();
     }
 
     @Override
     public void focusLost(FocusEvent e) {
-        c.repaint();
+      getComponent().repaint();
     }
-    });
+  };
 
+  @SuppressWarnings({"MethodOverridesStaticMethodOfSuperclass", "UnusedDeclaration"})
+  public static ComponentUI createUI(final JComponent c) {
     return new DarculaPasswordFieldUI();
   }
 
+  @Override
+  protected void installListeners() {
+    super.installListeners();
+    getComponent().addFocusListener(myFocusListener);
+  }
+
+  @Override
+  protected void uninstallListeners() {
+    getComponent().removeFocusListener(myFocusListener);
+    super.uninstallListeners();
+  }
+
   @Override
   protected void paintBackground(Graphics graphics) {
     Graphics2D g = (Graphics2D)graphics;

src/com/bulenkov/darcula/ui/DarculaTextFieldUI.java

@@ -32,62 +32,78 @@ import java.awt.event.*;
  * @author Konstantin Bulenkov
  */
 public class DarculaTextFieldUI extends BasicTextFieldUI {
-  private enum SearchAction {POPUP, CLEAR}
-
-  private final JTextField myTextField;
-  protected JLabel myClearIcon;
-  protected JLabel myRecentIcon;
 
-  public DarculaTextFieldUI(JTextField textField) {
+  private final FocusListener myFocusListener = new FocusAdapter() {
-    myTextField = textField;
-  }
-
-  @SuppressWarnings("MethodOverridesStaticMethodOfSuperclass")
-  public static ComponentUI createUI(final JComponent c) {
-    final DarculaTextFieldUI ui = new DarculaTextFieldUI((JTextField)c);
-    c.addFocusListener(new FocusAdapter() {
     @Override
     public void focusGained(FocusEvent e) {
-        c.repaint();
+      getComponent().repaint();
     }
 
     @Override
     public void focusLost(FocusEvent e) {
-        c.repaint();
+      getComponent().repaint();
     }
-    });
+  };
-    c.addMouseMotionListener(new MouseMotionAdapter() {
+
+  private final MouseMotionListener myMouseMotionListener = new MouseMotionAdapter() {
     @Override
     public void mouseMoved(MouseEvent e) {
-        if (ui.getComponent() != null && isSearchField(c)) {
+      if (getComponent() != null && isSearchField(getComponent())) {
-          if (ui.getActionUnder(e) != null) {
+        if (getActionUnder(e) != null) {
-            c.setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
+          getComponent().setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
         } else {
-            c.setCursor(Cursor.getPredefinedCursor(Cursor.TEXT_CURSOR));
+          getComponent().setCursor(Cursor.getPredefinedCursor(Cursor.TEXT_CURSOR));
         }
       }
     }
-    });
+  };
-    c.addMouseListener(new MouseAdapter() {
+
+  private final MouseListener myMouseListener = new MouseAdapter() {
     @Override
     public void mouseClicked(MouseEvent e) {
-        if (isSearchField(c)) {
+      if (isSearchField(getComponent())) {
-          final SearchAction action = ui.getActionUnder(e);
+        final SearchAction action = getActionUnder(e);
         if (action != null) {
           switch (action) {
             case POPUP:
-                ui.showSearchPopup();
+              showSearchPopup();
               break;
             case CLEAR:
-                ((JTextField)c).setText("");
+              getComponent().setText("");
               break;
           }
           e.consume();
         }
       }
     }
-    });
+  };
-    return ui;
+
+  private enum SearchAction {POPUP, CLEAR}
+
+  protected JLabel myClearIcon;
+  protected JLabel myRecentIcon;
+
+  @SuppressWarnings("MethodOverridesStaticMethodOfSuperclass")
+  public static ComponentUI createUI(final JComponent c) {
+    return new DarculaTextFieldUI();
+  }
+
+  @Override
+  protected void installListeners() {
+    super.installListeners();
+    final JTextComponent c = getComponent();
+    c.addFocusListener(myFocusListener);
+    c.addMouseMotionListener(myMouseMotionListener);
+    c.addMouseListener(myMouseListener);
+  }
+
+  @Override
+  protected void uninstallListeners() {
+    final JTextComponent c = getComponent();
+    c.removeMouseListener(myMouseListener);
+    c.removeMouseMotionListener(myMouseMotionListener);
+    c.removeFocusListener(myFocusListener);
+    super.uninstallListeners();
   }
 
   protected void showSearchPopup() {
@@ -110,7 +126,7 @@ public class DarculaTextFieldUI extends BasicTextFieldUI {
   }
 
   protected Rectangle getDrawingRect() {
-    final JTextComponent c = myTextField;
+    final JTextComponent c = getComponent();
     final Insets i = c.getInsets();
     final int x = i.right - 4 - 16;
     final int y = i.top - 3;