Add Engine#shutdown method and shutdown events

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

@@ -20,6 +20,8 @@
 package de.staropensource.sosengine.base;
 
 import de.staropensource.sosengine.base.data.info.EngineInformation;
+import de.staropensource.sosengine.base.events.EngineShutdownEvent;
+import de.staropensource.sosengine.base.events.internal.InternalEngineShutdownEvent;
 import de.staropensource.sosengine.base.logging.CrashHandler;
 import de.staropensource.sosengine.base.logging.LoggerInstance;
 import de.staropensource.sosengine.base.types.CodePart;
@@ -27,6 +29,7 @@ import de.staropensource.sosengine.base.types.LogIssuer;
 import de.staropensource.sosengine.base.utility.*;
 import lombok.Getter;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Range;
 
 import java.util.LinkedHashMap;
 import java.util.Map;
@@ -164,4 +167,25 @@ public final class Engine {
         CrashHandler.getCrashContent().put("Operating system", crashContentOS);
         CrashHandler.getCrashContent().put("Stacktrace", "%stacktrace%");
     }
+
+    /**
+     * Shuts the engine and JVM down.
+     *
+     * @param exitCode the code to exit with, from 0-255
+     * @since 1-alpha0
+     */
+    public void shutdown(@Range(from = 0, to = 255) int exitCode) {
+        new EngineShutdownEvent().callEvent();
+        new InternalEngineShutdownEvent().callEvent();
+        Runtime.getRuntime().exit(exitCode);
+    }
+
+    /**
+     * Shuts the engine and JVM down.
+     *
+     * @since 1-alpha0
+     */
+    public void shutdown() {
+        shutdown(0);
+    }
 }

base/src/main/java/de/staropensource/sosengine/base/events/EngineShutdownEvent.java

@@ -0,0 +1,36 @@
+/*
+    STAROPENSOURCE ENGINE SOURCE FILE
+    Copyright (c) 2024 The StarOpenSource Engine Contributors
+    Licensed under the GNU Affero General Public License v3
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as
+    published by the Free Software Foundation, either version 3 of the
+    License, or (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.staropensource.sosengine.base.events;
+
+import de.staropensource.sosengine.base.classes.Event;
+import de.staropensource.sosengine.base.classes.helpers.EventHelper;
+
+/**
+ * Called when the engine and JVM are about to shutdown.
+ *
+ * @since 1-alpha0
+ */
+public class EngineShutdownEvent implements Event {
+    /** {@inheritDoc} */
+    @Override
+    public void callEvent() {
+        EventHelper.invokeAnnotatedMethods(getClass());
+    }
+}

base/src/main/java/de/staropensource/sosengine/base/events/internal/InternalEngineShutdownEvent.java

@@ -0,0 +1,36 @@
+/*
+    STAROPENSOURCE ENGINE SOURCE FILE
+    Copyright (c) 2024 The StarOpenSource Engine Contributors
+    Licensed under the GNU Affero General Public License v3
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as
+    published by the Free Software Foundation, either version 3 of the
+    License, or (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package de.staropensource.sosengine.base.events.internal;
+
+import de.staropensource.sosengine.base.classes.Event;
+import de.staropensource.sosengine.base.classes.helpers.EventHelper;
+
+/**
+ * Called when the engine and JVM are about to shutdown, after {@link de.staropensource.sosengine.base.events.EngineShutdownEvent}.
+ *
+ * @since 1-alpha0
+ */
+public class InternalEngineShutdownEvent implements Event {
+    /** {@inheritDoc} */
+    @Override
+    public void callEvent() {
+        EventHelper.invokeAnnotatedMethods(getClass());
+    }
+}