Add command line parsing in GUI mode and headless Windows support

In GUI mode, a file name can be specified to open, and --headless can be
added to the command to make it not really open the GUI.

In headless mode, we don't really need to listen for hangup signals
(since the wrapper script will kill any old instances of GRIP), so we
can remove that to make it work on non-unix systems.

Author: ThomasJClark

core/src/main/java/edu/wpi/grip/core/Main.java

@@ -8,9 +8,7 @@
 import edu.wpi.grip.core.events.ExceptionEvent;
 import edu.wpi.grip.core.operations.Operations;
 import edu.wpi.grip.core.serialization.Project;
-import edu.wpi.grip.core.util.SafeShutdown;
 import edu.wpi.grip.generated.CVOperations;
-import sun.misc.Signal;
 
 import javax.inject.Inject;
 import java.io.File;
@@ -23,22 +21,13 @@
  */
 public class Main {
 
-    @Inject
-    private Project project;
-    @Inject
-    private PipelineRunner pipelineRunner;
-    @Inject
-    private EventBus eventBus;
-    @Inject
-    private Logger logger;
+    @Inject private Project project;
+    @Inject private PipelineRunner pipelineRunner;
+    @Inject private EventBus eventBus;
+    @Inject private Logger logger;
 
     @SuppressWarnings("PMD.SystemPrintln")
     public static void main(String[] args) throws IOException, InterruptedException {
-        // Close GRIP when we get SIGHUP.  This signal is sent, for example, when GRIP is run in an SSH session
-        // and the session is closed.
-        Signal.handle(new Signal("HUP"), signal -> SafeShutdown.exit(0));
-
-        System.out.println("Loading Dependency Injection Framework");
         final Injector injector = Guice.createInjector(new GRIPCoreModule());
         injector.getInstance(Main.class).start(args);
     }

ui/src/main/java/edu/wpi/grip/ui/Main.java

@@ -7,10 +7,10 @@
 import com.google.inject.Injector;
 import com.sun.javafx.application.PlatformImpl;
 import edu.wpi.grip.core.GRIPCoreModule;
-import edu.wpi.grip.core.Palette;
 import edu.wpi.grip.core.PipelineRunner;
 import edu.wpi.grip.core.events.UnexpectedThrowableEvent;
 import edu.wpi.grip.core.operations.Operations;
+import edu.wpi.grip.core.serialization.Project;
 import edu.wpi.grip.core.util.SafeShutdown;
 import edu.wpi.grip.generated.CVOperations;
 import edu.wpi.grip.ui.util.DPIUtility;
@@ -23,19 +23,19 @@
 import javafx.stage.Stage;
 
 import javax.inject.Inject;
+import java.io.File;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
 public class Main extends Application {
 
-    @Inject
-    private EventBus eventBus;
-    @Inject
-    private Palette palette;
-    @Inject
-    private PipelineRunner pipelineRunner;
-    @Inject
-    private Logger logger;
+    @Inject private EventBus eventBus;
+    @Inject private PipelineRunner pipelineRunner;
+    @Inject private Project project;
+    @Inject private Logger logger;
 
     @VisibleForTesting
     protected final Injector injector = Guice.createInjector(new GRIPCoreModule(), new GRIPUIModule());
@@ -58,25 +58,37 @@ public Main() {
     @Override
     @SuppressWarnings("PMD.SignatureDeclareThrowsException")
     public void start(Stage stage) throws Exception {
-        root = FXMLLoader.load(Main.class.getResource("MainWindow.fxml"), null, null, injector::getInstance);
-        root.setStyle("-fx-font-size: " + DPIUtility.FONT_SIZE + "px");
+        // If --headless was specified on the command line, run in headless mode
+        List<String> parameters = new ArrayList<>(getParameters().getRaw());
+
+        if (parameters.contains("--headless")) {
+            parameters.remove("--headless");
+        } else {
+            root = FXMLLoader.load(Main.class.getResource("MainWindow.fxml"), null, null, injector::getInstance);
+            root.setStyle("-fx-font-size: " + DPIUtility.FONT_SIZE + "px");
+
+            // If this isn't here this can cause a deadlock on windows. See issue #297
+            stage.setOnCloseRequest(event -> SafeShutdown.exit(0, Platform::exit));
+            stage.setTitle("GRIP Computer Vision Engine");
+            stage.getIcons().add(new Image("/edu/wpi/grip/ui/icons/grip.png"));
+            stage.setScene(new Scene(root));
+            stage.show();
+        }
 
         Operations.addOperations(eventBus);
         CVOperations.addOperations(eventBus);
 
-        stage.setOnCloseRequest((event) -> {
-            // If this isn't here this can cause a deadlock on windows
-            // See issue #297
-            SafeShutdown.exit(0, Platform::exit);
-        });
+        // If there was a file specified on the command line, open it immediately
+        if (!parameters.isEmpty()) {
+            try {
+                project.open(new File(parameters.get(0)));
+            } catch (IOException e) {
+                logger.log(Level.SEVERE, "Error loading file: " + parameters.get(0));
+                throw e;
+            }
+        }
 
         pipelineRunner.startAsync();
-
-        stage.setTitle("GRIP Computer Vision Engine");
-        stage.getIcons().add(new Image("/edu/wpi/grip/ui/icons/grip.png"));
-        stage.setScene(new Scene(root));
-        stage.show();
-
     }
 
     public void stop() {