Handle suspend/resume if serial port disappears

Similar to minicom behaviour.
Automatically reopens the port only if it takes the same name (could be improved based on vid/pid)

app/src/processing/app/AbstractMonitor.java

@@ -1,6 +1,7 @@
 package processing.app;
 
 import cc.arduino.packages.BoardPort;
+import cc.arduino.packages.DiscoveryManager;
 import processing.app.legacy.PApplet;
 
 import javax.swing.*;
@@ -9,6 +10,7 @@
 import java.awt.event.ActionListener;
 import java.awt.event.WindowAdapter;
 import java.awt.event.WindowEvent;
+import java.util.List;
 
 @SuppressWarnings("serial")
 public abstract class AbstractMonitor extends JFrame implements ActionListener {
@@ -17,6 +19,7 @@ public abstract class AbstractMonitor extends JFrame implements ActionListener {
 
   private StringBuffer updateBuffer;
   private Timer updateTimer;
+  private Timer portExistsTimer;
 
   private BoardPort boardPort;
 
@@ -73,6 +76,26 @@ public void actionPerformed(ActionEvent event) {
     updateTimer = new Timer(33, this);  // redraw serial monitor at 30 Hz
     updateTimer.start();
 
+    ActionListener portExists = new ActionListener() {
+      @Override
+      public void actionPerformed(ActionEvent ae) {
+        try {
+          if (!Base.getDiscoveryManager().discovery().contains(boardPort)) {
+            if (!closed) {
+              suspend();
+            }
+          } else {
+            if (closed) {
+              resume(boardPort);
+            }
+          }
+        } catch (Exception e) {}
+      }
+    };
+
+    portExistsTimer = new Timer(1000, portExists);  // check if the port is still there every second
+    portExistsTimer.start();
+
     closed = false;
   }
 
@@ -92,6 +115,11 @@ public void suspend() throws Exception {
     close();
   }
 
+  public void dispose() {
+    super.dispose();
+    portExistsTimer.stop();
+  }
+
   public void resume(BoardPort boardPort) throws Exception {
     setBoardPort(boardPort);