Fix compiler/IDE warnings in monitor classes + Code cleanup

No functional changes:
- Fix compiler/IDE warnings in monitor classes.
- Replace listeners to use lambda classes where convenient in monitor classes.
- Code cleanup.

app/src/processing/app/AbstractMonitor.java

@@ -27,6 +27,7 @@ public abstract class AbstractMonitor extends JFrame implements ActionListener {
     this.boardPort = boardPort;
 
     addWindowListener(new WindowAdapter() {
+      @Override
       public void windowClosing(WindowEvent event) {
         try {
           closed = true;
@@ -41,6 +42,7 @@ public abstract class AbstractMonitor extends JFrame implements ActionListener {
     KeyStroke wc = Editor.WINDOW_CLOSE_KEYSTROKE;
     getRootPane().getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT).put(wc, "close");
     getRootPane().getActionMap().put("close", (new AbstractAction() {
+      @Override
       public void actionPerformed(ActionEvent event) {
         try {
           close();
@@ -165,6 +167,7 @@ public abstract class AbstractMonitor extends JFrame implements ActionListener {
     return s;
   }
 
+  @Override
   public void actionPerformed(ActionEvent e) {
     String s = consumeUpdateBuffer();
     if (s.isEmpty()) {

app/src/processing/app/AbstractTextMonitor.java

@@ -45,14 +45,15 @@ public abstract class AbstractTextMonitor extends AbstractMonitor {
   protected JButton clearButton;
   protected JCheckBox autoscrollBox;
   protected JCheckBox addTimeStampBox;
-  protected JComboBox lineEndings;
-  protected JComboBox serialRates;
+  protected JComboBox<String> lineEndings;
+  protected JComboBox<String> serialRates;
 
   public AbstractTextMonitor(Base base, BoardPort boardPort) {
     super(boardPort);
     this.base = base;
   }
 
+  @Override
   protected void onCreateWindow(Container mainPane) {
 
     mainPane.setLayout(new BorderLayout());
@@ -111,6 +112,7 @@ public abstract class AbstractTextMonitor extends AbstractMonitor {
     textField = new JTextField(40);
     // textField is selected every time the window is focused
     addWindowFocusListener(new WindowAdapter() {
+      @Override
       public void windowGainedFocus(WindowEvent e) {
         textField.requestFocusInWindow();
       }
@@ -139,22 +141,17 @@ public abstract class AbstractTextMonitor extends AbstractMonitor {
     minimumSize.setSize(minimumSize.getWidth() / 3, minimumSize.getHeight());
     noLineEndingAlert.setMinimumSize(minimumSize);
 
-    lineEndings = new JComboBox(new String[]{tr("No line ending"), tr("Newline"), tr("Carriage return"), tr("Both NL & CR")});
-    lineEndings.addActionListener(new ActionListener() {
-      public void actionPerformed(ActionEvent event) {
-        PreferencesData.setInteger("serial.line_ending", lineEndings.getSelectedIndex());
-        noLineEndingAlert.setForeground(pane.getBackground());
-      }
-    });
-    addTimeStampBox.addActionListener(new ActionListener() {
-      public void actionPerformed(ActionEvent e) {
-        PreferencesData.setBoolean("serial.show_timestamp", addTimeStampBox.isSelected());
-      }
+    lineEndings = new JComboBox<String>(new String[]{tr("No line ending"), tr("Newline"), tr("Carriage return"), tr("Both NL & CR")});
+    lineEndings.addActionListener((ActionEvent event) -> {
+      PreferencesData.setInteger("serial.line_ending", lineEndings.getSelectedIndex());
+      noLineEndingAlert.setForeground(pane.getBackground());
     });
+    addTimeStampBox.addActionListener((ActionEvent event) ->
+        PreferencesData.setBoolean("serial.show_timestamp", addTimeStampBox.isSelected()));
 
     lineEndings.setMaximumSize(lineEndings.getMinimumSize());
 
-    serialRates = new JComboBox();
+    serialRates = new JComboBox<String>();
     for (String rate : serialRateStrings) {
       serialRates.addItem(rate + " " + tr("baud"));
     }
@@ -177,6 +174,7 @@ public abstract class AbstractTextMonitor extends AbstractMonitor {
     mainPane.add(pane, BorderLayout.SOUTH);
   }
 
+  @Override
   protected void onEnableWindow(boolean enable)
   {
     textArea.setEnabled(enable);
@@ -203,6 +201,7 @@ public abstract class AbstractTextMonitor extends AbstractMonitor {
     serialRates.addActionListener(listener);
   }
 
+  @Override
   public void message(String msg) {
     SwingUtilities.invokeLater(() -> updateTextArea(msg));
   }

app/src/processing/app/EditorTab.java

@@ -110,7 +110,7 @@ public class EditorTab extends JPanel implements SketchFile.TextStorage, MouseWh
     file.setStorage(this);
     applyPreferences();
     add(scrollPane, BorderLayout.CENTER);
-	textarea.addMouseWheelListener(this);
+    textarea.addMouseWheelListener(this);
   }
 
   private RSyntaxDocument createDocument(String contents) {

app/src/processing/app/SerialMonitor.java

@@ -21,9 +21,8 @@ package processing.app;
 import cc.arduino.packages.BoardPort;
 import processing.app.legacy.PApplet;
 
-import java.awt.*;
+import java.awt.Color;
 import java.awt.event.ActionEvent;
-import java.awt.event.ActionListener;
 
 import static processing.app.I18n.tr;
 
@@ -38,36 +37,28 @@ public class SerialMonitor extends AbstractTextMonitor {
 
     serialRate = PreferencesData.getInteger("serial.debug_rate");
     serialRates.setSelectedItem(serialRate + " " + tr("baud"));
-    onSerialRateChange(new ActionListener() {
-      public void actionPerformed(ActionEvent event) {
-        String wholeString = (String) serialRates.getSelectedItem();
-        String rateString = wholeString.substring(0, wholeString.indexOf(' '));
-        serialRate = Integer.parseInt(rateString);
-        PreferencesData.set("serial.debug_rate", rateString);
-        try {
-          close();
-          Thread.sleep(100); // Wait for serial port to properly close
-          open();
-        } catch (InterruptedException e) {
-          // noop
-        } catch (Exception e) {
-          System.err.println(e);
-        }
+    onSerialRateChange((ActionEvent event) -> {
+      String wholeString = (String) serialRates.getSelectedItem();
+      String rateString = wholeString.substring(0, wholeString.indexOf(' '));
+      serialRate = Integer.parseInt(rateString);
+      PreferencesData.set("serial.debug_rate", rateString);
+      try {
+        close();
+        Thread.sleep(100); // Wait for serial port to properly close
+        open();
+      } catch (InterruptedException e) {
+        // noop
+      } catch (Exception e) {
+        System.err.println(e);
       }
     });
 
-    onSendCommand(new ActionListener() {
-      public void actionPerformed(ActionEvent e) {
-        send(textField.getText());
-        textField.setText("");
-      }
+    onSendCommand((ActionEvent event) -> {
+      send(textField.getText());
+      textField.setText("");
     });
     
-    onClearCommand(new ActionListener() {
-      public void actionPerformed(ActionEvent e) {
-        textArea.setText("");
-      }
-    });
+    onClearCommand((ActionEvent event) -> textArea.setText(""));
   }
 
   private void send(String s) {
@@ -93,6 +84,7 @@ public class SerialMonitor extends AbstractTextMonitor {
     }
   }
 
+  @Override
   public void open() throws Exception {
     super.open();
 
@@ -106,6 +98,7 @@ public class SerialMonitor extends AbstractTextMonitor {
     };
   }
 
+  @Override
   public void close() throws Exception {
     super.close();
     if (serial != null) {