Fixed NPE introduced in 125846f

Fix #6552

Author: cmaglie

arduino-core/src/processing/app/Serial.java

@@ -65,34 +65,34 @@ public Serial() throws SerialException {
       PreferencesData.getNonEmpty("serial.parity", "N").charAt(0),
       PreferencesData.getInteger("serial.databits", 8),
       PreferencesData.getFloat("serial.stopbits", 1),
-      !BaseNoGui.getBoardPreferences().get("serial.disableRTS").equalsIgnoreCase("true"),
-      !BaseNoGui.getBoardPreferences().get("serial.disableDTR").equalsIgnoreCase("true"));
+      !BaseNoGui.getBoardPreferences().getBoolean("serial.disableRTS"),
+      !BaseNoGui.getBoardPreferences().getBoolean("serial.disableDTR"));
   }
 
   public Serial(int irate) throws SerialException {
     this(PreferencesData.get("serial.port"), irate,
       PreferencesData.getNonEmpty("serial.parity", "N").charAt(0),
       PreferencesData.getInteger("serial.databits", 8),
       PreferencesData.getFloat("serial.stopbits", 1),
-      !BaseNoGui.getBoardPreferences().get("serial.disableRTS").equalsIgnoreCase("true"),
-      !BaseNoGui.getBoardPreferences().get("serial.disableDTR").equalsIgnoreCase("true"));
+      !BaseNoGui.getBoardPreferences().getBoolean("serial.disableRTS"),
+      !BaseNoGui.getBoardPreferences().getBoolean("serial.disableDTR"));
   }
 
   public Serial(String iname, int irate) throws SerialException {
     this(iname, irate, PreferencesData.getNonEmpty("serial.parity", "N").charAt(0),
       PreferencesData.getInteger("serial.databits", 8),
       PreferencesData.getFloat("serial.stopbits", 1),
-      !BaseNoGui.getBoardPreferences().get("serial.disableRTS").equalsIgnoreCase("true"),
-      !BaseNoGui.getBoardPreferences().get("serial.disableDTR").equalsIgnoreCase("true"));
+      !BaseNoGui.getBoardPreferences().getBoolean("serial.disableRTS"),
+      !BaseNoGui.getBoardPreferences().getBoolean("serial.disableDTR"));
   }
 
   public Serial(String iname) throws SerialException {
     this(iname, PreferencesData.getInteger("serial.debug_rate", 9600),
       PreferencesData.getNonEmpty("serial.parity", "N").charAt(0),
       PreferencesData.getInteger("serial.databits", 8),
       PreferencesData.getFloat("serial.stopbits", 1),
-      !BaseNoGui.getBoardPreferences().get("serial.disableRTS").equalsIgnoreCase("true"),
-      !BaseNoGui.getBoardPreferences().get("serial.disableDTR").equalsIgnoreCase("true"));
+      !BaseNoGui.getBoardPreferences().getBoolean("serial.disableRTS"),
+      !BaseNoGui.getBoardPreferences().getBoolean("serial.disableDTR"));
   }
 
   public static boolean touchForCDCReset(String iname) throws SerialException {