Optimize startup and fix shutdown logic

base/src/main/java/de/staropensource/sosengine/base/Engine.java

@@ -355,6 +355,20 @@ public final class Engine implements SubsystemMainClass {
      * @since v1-alpha0
      */
     public synchronized void shutdown(@Range(from = 0, to = 255) int exitCode) {
+        if (shuttingDown) {
+            logger.error("Already shutting down");
+            return;
+        }
+
+        // Make engine single-threaded
+        Properties properties = new Properties();
+        properties.setProperty("sosengine.base.optimizeLogging", "false");
+        properties.setProperty("sosengine.base.optimizeEvents", "false");
+        EngineConfiguration.getInstance().loadConfiguration(properties);
+
+        // Flush log messages
+        Logger.flushLogMessages();
+
         logger.info("Shutting engine down");
         shuttingDown = true;
 
@@ -365,10 +379,18 @@ public final class Engine implements SubsystemMainClass {
         new InternalEngineShutdownEvent().callEvent();
 
         logger.verb("Shutting down JVM with code " + exitCode);
-        Logger.flushLogMessages();  // Flush all log messages before exiting
         Runtime.getRuntime().exit(exitCode);
     }
 
+    /**
+     * Shuts the engine and JVM down.
+     *
+     * @since v1-alpha0
+     */
+    public void shutdown() {
+        shutdown(0);
+    }
+
     /**
      * {@inheritDoc}
      */
@@ -393,13 +415,4 @@ public final class Engine implements SubsystemMainClass {
     public DependencyVector getDependencyVector() {
         return new DependencyVector("engine", StarOpenSourceVersioningSystem.class, EngineInformation.getVersioningString());
     }
-
-    /**
-     * Shuts the engine and JVM down.
-     *
-     * @since v1-alpha0
-     */
-    public synchronized void shutdown() {
-        shutdown(0);
-    }
 }

base/src/main/java/de/staropensource/sosengine/base/EngineConfiguration.java

@@ -298,7 +298,8 @@ public final class EngineConfiguration implements SubsystemConfiguration {
         // Loop through all properties
         for (String property : properties.stringPropertyNames()) {
             // Check if property name starts with group
-            if (!property.startsWith(group)) continue;
+            if (!property.startsWith(group))
+                continue;
 
             // Skip to important stuff
             property = property.substring(group.length());

graphics/glfw/src/main/java/de/staropensource/sosengine/graphics/glfw/GlfwSubsystem.java

@@ -20,18 +20,17 @@
 package de.staropensource.sosengine.graphics.glfw;
 
 import de.staropensource.sosengine.base.annotations.EngineSubsystem;
-import de.staropensource.sosengine.base.annotations.EventListener;
 import de.staropensource.sosengine.base.classes.SubsystemMainClass;
 import de.staropensource.sosengine.base.data.info.EngineInformation;
 import de.staropensource.sosengine.base.data.versioning.StarOpenSourceVersioningSystem;
-import de.staropensource.sosengine.base.internal.events.InternalEngineShutdownEvent;
 import de.staropensource.sosengine.base.logging.LoggerInstance;
 import de.staropensource.sosengine.base.types.CodePart;
 import de.staropensource.sosengine.base.types.DependencyVector;
-import de.staropensource.sosengine.base.types.EventPriority;
 import de.staropensource.sosengine.base.types.logging.LogIssuer;
+import de.staropensource.sosengine.base.utility.Miscellaneous;
 import de.staropensource.sosengine.graphics.glfw.events.GraphicsErrorEvent;
 import de.staropensource.sosengine.graphics.glfw.exceptions.GlfwInitializationException;
+import de.staropensource.sosengine.graphics.glfw.exceptions.NotOnMainThreadException;
 import lombok.Getter;
 import org.jetbrains.annotations.NotNull;
 import org.lwjgl.glfw.GLFWErrorCallback;
@@ -70,6 +69,15 @@ public class GlfwSubsystem implements SubsystemMainClass {
      */
     private final LoggerInstance logger = new LoggerInstance(new LogIssuer(getClass(), CodePart.ENGINE));
 
+    /**
+     * The {@link GLFWErrorCallback} to use.
+     * <p>
+     * Only declared publicly for freeing during engine shutdown.
+     *
+     * @since v1-alpha2
+     */
+    private final GLFWErrorCallback errorCallback = GLFWErrorCallback.create(new GraphicsErrorEvent());
+
     /**
      * Constructs this subsystem.
      *
@@ -107,11 +115,16 @@ public class GlfwSubsystem implements SubsystemMainClass {
      * @since v1-alpha2
      */
     public void initializeGlfw() {
-        // Set error callback
+        logger.verb("Initializing GLFW");
-        try (GLFWErrorCallback errorCallback = GLFWErrorCallback.create(new GraphicsErrorEvent())) {
+
-            errorCallback.set();
+        if (!Miscellaneous.onMainThread()) {
+            logger.crash("Unable to initialize GLFW on a non-main thread", new NotOnMainThreadException(), true);
+            return;
         }
 
+        // Set error callback
+        errorCallback.set();
+
         // Initialize GLFW
         if (!glfwInit())
             throw new GlfwInitializationException();
@@ -125,19 +138,12 @@ public class GlfwSubsystem implements SubsystemMainClass {
     public void terminateGlfw() {
         logger.verb("Terminating GLFW");
 
-        glfwTerminate();
+        if (!Miscellaneous.onMainThread()) {
-        //noinspection DataFlowIssue,resource
+            logger.crash("Unable to terminate GLFW on a non-main thread. Did you call Engine#shutdown or Logger#crash from another thread?", new NotOnMainThreadException(), true);
-        glfwSetErrorCallback(null).free();
+            return;
-    }
+        }
 
-    /**
+        glfwTerminate();
-     * Called when the engine shuts down.
+        errorCallback.free();
-     *
-     * @since v1-alpha2
-     */
-    @EventListener(event = InternalEngineShutdownEvent.class, priority = EventPriority.EXTREMELY_UNIMPORTANT)
-    private static void shutdownApiFromEvent() {
-        if (instance != null)
-            instance.terminateGlfw();
     }
 }

graphics/src/main/java/de/staropensource/sosengine/graphics/GraphicsSubsystem.java

@@ -29,7 +29,6 @@ import de.staropensource.sosengine.base.internal.events.InternalEngineShutdownEv
 import de.staropensource.sosengine.base.logging.LoggerInstance;
 import de.staropensource.sosengine.base.types.CodePart;
 import de.staropensource.sosengine.base.types.DependencyVector;
-import de.staropensource.sosengine.base.types.EventPriority;
 import de.staropensource.sosengine.base.types.logging.LogIssuer;
 import de.staropensource.sosengine.base.utility.ListFormatter;
 import de.staropensource.sosengine.base.utility.Miscellaneous;
@@ -161,12 +160,17 @@ public final class GraphicsSubsystem implements SubsystemMainClass {
      * 
      * @since v1-alpha0
      */
-    @EventListener(event = InternalEngineShutdownEvent.class, priority = EventPriority.EXTREMELY_UNIMPORTANT)
+    @EventListener(event = InternalEngineShutdownEvent.class)
-    public static void shutdown() {
+    private static void shutdown() {
         LoggerInstance logger = instance.logger;
         logger.verb("Shutting down");
 
-        long shutdownTime = Miscellaneous.measureExecutionTime(() -> new GraphicsApiShutdownEvent().callEvent());
+        long shutdownTime = Miscellaneous.measureExecutionTime(() -> {
+            new GraphicsApiShutdownEvent().callEvent();
+
+            if (instance.api != null)
+                instance.api.shutdownApi();
+        });
 
         logger.info("Shut down in " + shutdownTime + "ms");
     }
@@ -201,7 +205,7 @@ public final class GraphicsSubsystem implements SubsystemMainClass {
         // Check if registered apis are compatible
         for (String apiName : registeredApis.keySet())
             if (registeredApis.get(apiName).isCompatible()) {
-                logger.diag("" + apiName + " is compatible");
+                logger.diag(apiName + " is compatible");
                 compatibleApis.add(apiName);
             } else
                 logger.diag(apiName + " is not compatible");

testapp/src/main/java/de/staropensource/sosengine/testapp/Main.java

@@ -20,16 +20,20 @@
 package de.staropensource.sosengine.testapp;
 
 import de.staropensource.sosengine.base.Engine;
+import de.staropensource.sosengine.base.annotations.EventListener;
+import de.staropensource.sosengine.base.events.ThrowableCatchEvent;
 import de.staropensource.sosengine.base.logging.LoggerInstance;
 import de.staropensource.sosengine.base.types.CodePart;
 import de.staropensource.sosengine.base.types.logging.LogIssuer;
 import de.staropensource.sosengine.base.types.vectors.Vec2i;
+import de.staropensource.sosengine.base.utility.Miscellaneous;
 import de.staropensource.sosengine.graphics.GraphicsSubsystem;
 import de.staropensource.sosengine.graphics.classes.ApiMainClass;
 import de.staropensource.sosengine.graphics.classes.ApiManagementClass;
 import de.staropensource.sosengine.graphics.classes.Window;
 import lombok.Getter;
 import lombok.SneakyThrows;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * The initialization class for sos!engine's development application.
@@ -78,7 +82,7 @@ public class Main {
 
     /**
      * The program's entrypoint.
-     * Calls {@code run()} after invocation.
+     * Calls {@link #run(String[])} after invocation.
      *
      * @see Main#run(String[])
      * @param args program's command line arguments
@@ -88,15 +92,15 @@ public class Main {
     }
 
     /**
-     * The program's entrypoint but not static.
+     * The program's entrypoint except it's not static.
-     * Here's where the "real magic" happens-
+     * Here's where the "real magic" happens.
      *
      * @see Main#main(String[])
      * @param args program's command line arguments
      */
     @SneakyThrows
     public void run(String[] args) {
-        try {
+        Miscellaneous.executeSafely(() -> {
             // Initialize sos!engine
             engine = new Engine();
 
@@ -124,13 +128,27 @@ public class Main {
             }
 
             // Sleep for five seconds
-            Thread.sleep(5000);
+            try {
+                Thread.sleep(5000);
+            } catch (InterruptedException exception) {
+                logger.crash("Was unable to sleep for 5000ms", exception);
+            }
 
             // Shutdown
-            Engine.getInstance().shutdown(0);
+            Engine.getInstance().shutdown();
-        } catch (Throwable throwable) {
+        }, "mainThread");
-            Thread.ofVirtual().start(() -> Engine.getInstance().shutdown(69));
+    }
-            throw throwable;
+
+    /**
+     * Crashes the application when a throwable
+     * is thrown in {@link #run(String[])}.
+     *
+     * @since v1-alpha2
+     */
+    @EventListener(event = ThrowableCatchEvent.class)
+    public static void onThrowable(@NotNull Throwable throwable, @NotNull String identifier) {
+        if (identifier.equals("mainThread")) {
+            instance.logger.crash("The main thread threw an exception", throwable);
         }
     }
 }