Add support for Folia servers with scheduler adapter implementation

api/pom.xml

@@ -55,6 +55,12 @@
             <version>${project.parent.version}</version>
             <scope>compile</scope>
         </dependency>
+        <dependency>
+            <groupId>de.rapha149.signgui</groupId>
+            <artifactId>signgui-scheduler</artifactId>
+            <version>${project.parent.version}</version>
+            <scope>compile</scope>
+        </dependency>
         <dependency>
             <groupId>de.rapha149.signgui</groupId>
             <artifactId>signgui-1_8_R1</artifactId>

api/src/main/java/de/rapha149/signgui/SignGUI.java

@@ -3,9 +3,9 @@
 import de.rapha149.signgui.SignGUIAction.SignGUIActionInfo;
 import de.rapha149.signgui.exception.SignGUIException;
 import de.rapha149.signgui.exception.SignGUIVersionException;
+import de.rapha149.signgui.scheduler.SchedulerAdapterFactory;
 import de.rapha149.signgui.version.VersionMatcher;
 import org.apache.commons.lang.Validate;
-import org.bukkit.Bukkit;
 import org.bukkit.DyeColor;
 import org.bukkit.Location;
 import org.bukkit.Material;
@@ -108,7 +108,7 @@ public void open(Player player) throws SignGUIException {
                 };
 
                 if (callHandlerSynchronously)
-                    Bukkit.getScheduler().runTask(plugin, runnable);
+                    SchedulerAdapterFactory.getScheduler().runAtEntity(plugin, player, runnable, null);
                 else
                     runnable.run();
             });

api/src/main/java/de/rapha149/signgui/SignGUIAction.java

@@ -1,5 +1,6 @@
 package de.rapha149.signgui;
 
+import de.rapha149.signgui.scheduler.SchedulerAdapterFactory;
 import org.apache.commons.lang.Validate;
 import org.bukkit.Bukkit;
 import org.bukkit.entity.Player;
@@ -122,7 +123,7 @@ public SignGUIActionInfo getInfo() {
 
             @Override
             public void execute(SignGUI gui, SignEditor signEditor, Player player) {
-                Bukkit.getScheduler().runTask(plugin, () -> player.openInventory(inventory));
+                SchedulerAdapterFactory.getScheduler().runAtEntity(plugin, player, () -> player.openInventory(inventory), null);
             }
         };
     }
@@ -175,7 +176,7 @@ public SignGUIActionInfo getInfo() {
 
             @Override
             public void execute(SignGUI gui, SignEditor signEditor, Player player) {
-                Bukkit.getScheduler().runTask(plugin, runnable);
+                SchedulerAdapterFactory.getScheduler().runAtEntity(plugin, player, runnable, null);
             }
         };
     }

api/src/main/java/de/rapha149/signgui/SignGUIBuilder.java

@@ -6,7 +6,6 @@
 import org.bukkit.Location;
 import org.bukkit.Material;
 import org.bukkit.entity.Player;
-import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.java.JavaPlugin;
 
 import java.util.Arrays;
@@ -168,7 +167,9 @@ public SignGUIBuilder setHandler(SignGUIFinishHandler handler) {
     }
 
     /**
-     * If called the handler will be called synchronously by calling the method {@link org.bukkit.scheduler.BukkitScheduler#runTask(Plugin, Runnable)}
+     * If called the handler will be called synchronously on the player's thread.
+     * On Bukkit/Paper servers this runs on the main thread.
+     * On Folia servers this runs on the entity's region thread.
      *
      * @param plugin Your {@link org.bukkit.plugin.java.JavaPlugin} instance.
      * @return The {@link SignGUIBuilder} instance

pom.xml

@@ -12,6 +12,7 @@
     <modules>
         <module>api</module>
         <module>wrapper</module>
+        <module>scheduler</module>
         <module>1_8_R1</module>
         <module>1_8_R2</module>
         <module>1_8_R3</module>

scheduler/pom.xml

@@ -0,0 +1,47 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <artifactId>signgui-parent</artifactId>
+        <groupId>de.rapha149.signgui</groupId>
+        <version>2.5.4</version>
+    </parent>
+
+    <artifactId>signgui-scheduler</artifactId>
+
+    <properties>
+        <maven.deploy.skip>true</maven.deploy.skip>
+    </properties>
+
+    <repositories>
+        <repository>
+            <id>papermc</id>
+            <url>https://repo.papermc.io/repository/maven-public/</url>
+        </repository>
+    </repositories>
+
+    <dependencies>
+        <dependency>
+            <groupId>dev.folia</groupId>
+            <artifactId>folia-api</artifactId>
+            <version>1.20.1-R0.1-SNAPSHOT</version>
+            <scope>provided</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>8</source>
+                    <target>8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

scheduler/src/main/java/de/rapha149/signgui/scheduler/BukkitSchedulerAdapter.java

@@ -0,0 +1,66 @@
+package de.rapha149.signgui.scheduler;
+
+import org.bukkit.Bukkit;
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.bukkit.plugin.Plugin;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Scheduler adapter implementation for Bukkit/Paper/Spigot servers.
+ * All tasks run on the main server thread except for async tasks.
+ */
+public class BukkitSchedulerAdapter implements SchedulerAdapter {
+
+    @Override
+    public void runNextTick(Plugin plugin, Runnable runnable) {
+        Bukkit.getScheduler().runTask(plugin, runnable);
+    }
+
+    @Override
+    public void runNextTick(Plugin plugin, Runnable runnable, long delayTicks) {
+        Bukkit.getScheduler().runTaskLater(plugin, runnable, delayTicks);
+    }
+
+    @Override
+    public void runAsync(Plugin plugin, Runnable runnable) {
+        Bukkit.getScheduler().runTaskAsynchronously(plugin, runnable);
+    }
+
+    @Override
+    public void runAsync(Plugin plugin, Runnable runnable, long delayTicks) {
+        Bukkit.getScheduler().runTaskLaterAsynchronously(plugin, runnable, delayTicks);
+    }
+
+    @Override
+    public void runAtEntity(Plugin plugin, Entity entity, Runnable runnable, @Nullable Runnable retired) {
+        Bukkit.getScheduler().runTask(plugin, () -> {
+            if (entity.isValid()) {
+                runnable.run();
+            } else if (retired != null) {
+                retired.run();
+            }
+        });
+    }
+
+    @Override
+    public void runAtEntity(Plugin plugin, Entity entity, Runnable runnable, @Nullable Runnable retired, long delayTicks) {
+        Bukkit.getScheduler().runTaskLater(plugin, () -> {
+            if (entity.isValid()) {
+                runnable.run();
+            } else if (retired != null) {
+                retired.run();
+            }
+        }, delayTicks);
+    }
+
+    @Override
+    public void runAtLocation(Plugin plugin, Location location, Runnable runnable) {
+        Bukkit.getScheduler().runTask(plugin, runnable);
+    }
+
+    @Override
+    public void runAtLocation(Plugin plugin, Location location, Runnable runnable, long delayTicks) {
+        Bukkit.getScheduler().runTaskLater(plugin, runnable, delayTicks);
+    }
+}

scheduler/src/main/java/de/rapha149/signgui/scheduler/FoliaSchedulerAdapter.java

@@ -0,0 +1,53 @@
+package de.rapha149.signgui.scheduler;
+
+import org.bukkit.Bukkit;
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.bukkit.plugin.Plugin;
+
+/**
+ * Scheduler adapter implementation for Folia servers.
+ * Tasks are scheduled on the appropriate region threads.
+ */
+public class FoliaSchedulerAdapter implements SchedulerAdapter {
+
+    @Override
+    public void runNextTick(Plugin plugin, Runnable runnable) {
+        Bukkit.getGlobalRegionScheduler().run(plugin, task -> runnable.run());
+    }
+
+    @Override
+    public void runNextTick(Plugin plugin, Runnable runnable, long delayTicks) {
+        Bukkit.getGlobalRegionScheduler().runDelayed(plugin, task -> runnable.run(), delayTicks);
+    }
+
+    @Override
+    public void runAsync(Plugin plugin, Runnable runnable) {
+        Bukkit.getAsyncScheduler().runNow(plugin, task -> runnable.run());
+    }
+
+    @Override
+    public void runAsync(Plugin plugin, Runnable runnable, long delayTicks) {
+        Bukkit.getAsyncScheduler().runDelayed(plugin, task -> runnable.run(), delayTicks * 50, java.util.concurrent.TimeUnit.MILLISECONDS);
+    }
+
+    @Override
+    public void runAtEntity(Plugin plugin, Entity entity, Runnable runnable, Runnable retired) {
+        entity.getScheduler().run(plugin, task -> runnable.run(), retired);
+    }
+
+    @Override
+    public void runAtEntity(Plugin plugin, Entity entity, Runnable runnable, Runnable retired, long delayTicks) {
+        entity.getScheduler().runDelayed(plugin, task -> runnable.run(), retired, delayTicks);
+    }
+
+    @Override
+    public void runAtLocation(Plugin plugin, Location location, Runnable runnable) {
+        Bukkit.getRegionScheduler().run(plugin, location, task -> runnable.run());
+    }
+
+    @Override
+    public void runAtLocation(Plugin plugin, Location location, Runnable runnable, long delayTicks) {
+        Bukkit.getRegionScheduler().runDelayed(plugin, location, task -> runnable.run(), delayTicks);
+    }
+}

scheduler/src/main/java/de/rapha149/signgui/scheduler/SchedulerAdapter.java

@@ -0,0 +1,95 @@
+package de.rapha149.signgui.scheduler;
+
+import org.bukkit.Location;
+import org.bukkit.entity.Entity;
+import org.bukkit.plugin.Plugin;
+import org.jetbrains.annotations.Nullable;
+
+/**
+ * Adapter interface for scheduling tasks across different server implementations.
+ * Supports both Bukkit/Paper and Folia schedulers.
+ */
+public interface SchedulerAdapter {
+
+    /**
+     * Runs a task on the next server tick (main thread for Bukkit, global region for Folia).
+     *
+     * @param plugin   the plugin owning this task
+     * @param runnable the task to execute
+     */
+    void runNextTick(Plugin plugin, Runnable runnable);
+
+    /**
+     * Runs a task after a delay (main thread for Bukkit, global region for Folia).
+     *
+     * @param plugin   the plugin owning this task
+     * @param runnable the task to execute
+     * @param delayTicks the delay in ticks before execution
+     */
+    void runNextTick(Plugin plugin, Runnable runnable, long delayTicks);
+
+    /**
+     * Runs a task asynchronously.
+     *
+     * @param plugin   the plugin owning this task
+     * @param runnable the task to execute
+     */
+    void runAsync(Plugin plugin, Runnable runnable);
+
+    /**
+     * Runs a task asynchronously after a delay.
+     *
+     * @param plugin   the plugin owning this task
+     * @param runnable the task to execute
+     * @param delayTicks the delay in ticks before execution
+     */
+    void runAsync(Plugin plugin, Runnable runnable, long delayTicks);
+
+    /**
+     * Runs a task on the thread that owns the given entity.
+     * On Bukkit, this runs on the main thread.
+     * On Folia, this runs on the entity's region thread.
+     *
+     * @param plugin   the plugin owning this task
+     * @param entity   the entity to run the task for
+     * @param runnable the task to execute
+     * @param retired  called if the entity is removed before the task executes (may be null)
+     */
+    void runAtEntity(Plugin plugin, Entity entity, Runnable runnable, @Nullable Runnable retired);
+
+    /**
+     * Runs a task on the thread that owns the given entity after a delay.
+     * On Bukkit, this runs on the main thread.
+     * On Folia, this runs on the entity's region thread.
+     *
+     * @param plugin   the plugin owning this task
+     * @param entity   the entity to run the task for
+     * @param runnable the task to execute
+     * @param retired  called if the entity is removed before the task executes (may be null)
+     * @param delayTicks the delay in ticks before execution
+     */
+    void runAtEntity(Plugin plugin, Entity entity, Runnable runnable, @Nullable Runnable retired, long delayTicks);
+
+    /**
+     * Runs a task on the thread that owns the given location.
+     * On Bukkit, this runs on the main thread.
+     * On Folia, this runs on the region thread that owns the location.
+     *
+     * @param plugin   the plugin owning this task
+     * @param location the location to run the task at
+     * @param runnable the task to execute
+     */
+    void runAtLocation(Plugin plugin, Location location, Runnable runnable);
+
+    /**
+     * Runs a task on the thread that owns the given location after a delay.
+     * On Bukkit, this runs on the main thread.
+     * On Folia, this runs on the region thread that owns the location.
+     *
+     * @param plugin   the plugin owning this task
+     * @param location the location to run the task at
+     * @param runnable the task to execute
+     * @param delayTicks the delay in ticks before execution
+     */
+    void runAtLocation(Plugin plugin, Location location, Runnable runnable, long delayTicks);
+}