diff --git a/common/src/main/java/ctbrec/ForkProcessException.java b/common/src/main/java/ctbrec/ForkProcessException.java
new file mode 100644
index 00000000..53850559
--- /dev/null
+++ b/common/src/main/java/ctbrec/ForkProcessException.java
@@ -0,0 +1,9 @@
+package ctbrec;
+
+public class ForkProcessException extends RuntimeException {
+
+    public ForkProcessException(Exception e) {
+        super(e);
+    }
+
+}
diff --git a/common/src/main/java/ctbrec/OS.java b/common/src/main/java/ctbrec/OS.java
index 4214d4d0..4c26d3bd 100644
--- a/common/src/main/java/ctbrec/OS.java
+++ b/common/src/main/java/ctbrec/OS.java
@@ -13,21 +13,27 @@ import org.slf4j.LoggerFactory;
 
 public class OS {
 
-    private static final transient Logger LOG = LoggerFactory.getLogger(OS.class);
+    private static final Logger LOG = LoggerFactory.getLogger(OS.class);
 
-    public static enum TYPE {
+    private static final String USER_HOME = "user.home";
+    private static final String OS_NAME = "os.name";
+    private static final String CTBREC = "ctbrec";
+
+    public enum TYPE {
         LINUX,
         MAC,
         WINDOWS,
         OTHER
     }
 
+    private OS() {}
+
     public static TYPE getOsType() {
-        if(System.getProperty("os.name").contains("Linux")) {
+        if(System.getProperty(OS_NAME).contains("Linux")) {
             return TYPE.LINUX;
-        } else if(System.getProperty("os.name").contains("Windows")) {
+        } else if(System.getProperty(OS_NAME).contains("Windows")) {
             return TYPE.WINDOWS;
-        } else if(System.getProperty("os.name").contains("Mac")) {
+        } else if(System.getProperty(OS_NAME).contains("Mac")) {
             return TYPE.MAC;
         } else {
             return TYPE.OTHER;
@@ -38,26 +44,26 @@ public class OS {
         File configDir;
         switch (getOsType()) {
         case LINUX:
-            String userHome = System.getProperty("user.home");
-            configDir = new File(new File(userHome, ".config"), "ctbrec");
+            String userHome = System.getProperty(USER_HOME);
+            configDir = new File(new File(userHome, ".config"), CTBREC);
             break;
         case MAC:
-            userHome = System.getProperty("user.home");
+            userHome = System.getProperty(USER_HOME);
             configDir = new File(userHome, "Library/Preferences/ctbrec");
             break;
         case WINDOWS:
             String appData = System.getenv("APPDATA");
-            configDir = new File(appData, "ctbrec");
+            configDir = new File(appData, CTBREC);
             break;
         default:
-            throw new RuntimeException("Unsupported operating system " + System.getProperty("os.name"));
+            throw new UnsupportedOperatingSystemException("Unsupported operating system " + System.getProperty(OS_NAME));
         }
         return configDir;
     }
 
     public static String[] getBrowserCommand(String...args) {
         if(System.getenv("CTBREC_BROWSER") != null) {
-            String cmd[] = new String[args.length + 1];
+            String[] cmd = new String[args.length + 1];
             cmd[0] = System.getenv("CTBREC_BROWSER");
             System.arraycopy(args, 0, cmd, 1, args.length);
             return cmd;
@@ -86,27 +92,27 @@ public class OS {
                 System.arraycopy(args, 0, cmd, 2, args.length);
                 break;
             default:
-                throw new RuntimeException("Unsupported operating system " + System.getProperty("os.name"));
+                throw new UnsupportedOperatingSystemException("Unsupported operating system " + System.getProperty(OS_NAME));
             }
             LOG.debug("Browser command: {}", Arrays.toString(cmd));
             return cmd;
         } catch (URISyntaxException e) {
-            throw new RuntimeException(e);
+            throw new ForkProcessException(e);
         }
     }
 
     public static Settings getDefaultSettings() {
         Settings settings = new Settings();
         if(getOsType() == TYPE.WINDOWS) {
-            String userHome = System.getProperty("user.home");
-            Path path = Paths.get(userHome, "Videos", "ctbrec");
+            String userHome = System.getProperty(USER_HOME);
+            Path path = Paths.get(userHome, "Videos", CTBREC);
             settings.recordingsDir = path.toString();
             String programFiles = System.getenv("ProgramFiles");
             programFiles = programFiles != null ? programFiles : "C:\\Program Files";
             settings.mediaPlayer = Paths.get(programFiles, "VideoLAN", "VLC", "vlc.exe").toString();
         } else if(getOsType() == TYPE.MAC) {
-            String userHome = System.getProperty("user.home");
-            settings.recordingsDir = Paths.get(userHome, "Movies", "ctbrec").toString();
+            String userHome = System.getProperty(USER_HOME);
+            settings.recordingsDir = Paths.get(userHome, "Movies", CTBREC).toString();
             settings.mediaPlayer = "/Applications/VLC.app/Contents/MacOS/VLC";
         }
         return settings;
diff --git a/common/src/main/java/ctbrec/UnsupportedOperatingSystemException.java b/common/src/main/java/ctbrec/UnsupportedOperatingSystemException.java
new file mode 100644
index 00000000..69f9d456
--- /dev/null
+++ b/common/src/main/java/ctbrec/UnsupportedOperatingSystemException.java
@@ -0,0 +1,9 @@
+package ctbrec;
+
+public class UnsupportedOperatingSystemException extends RuntimeException {
+
+    public UnsupportedOperatingSystemException(String msg) {
+        super(msg);
+    }
+
+}