Support Minecraft 26.1 through 26.2, and fix the Base64Coder crash they introduce

.gitignore

@@ -133,4 +133,13 @@ $RECYCLE.BIN/
 # End of https://www.gitignore.io/api/java,windows,intellij
 
 # Claude Code documentation (local development only)
-CLAUDE.md
+CLAUDE.md
+
+# Maven build output
+target/
+
+# Folia notes (local only)
+FOLIA_COMPATIBILITY.md
+
+# Generated by maven-shade-plugin on every package
+dependency-reduced-pom.xml

README.md

@@ -2,7 +2,28 @@
  <img src="signshopheader.png" alt="SignShop LOGO">
 </p>
 
+## ⚡ Folia Compatible
 
+This fork adds **full Folia support** for multi-threaded servers while maintaining complete backward compatibility with Bukkit/Spigot/Paper.
+
+Scheduling goes through `SchedulerAdapter`, which picks Folia's region schedulers when it detects Folia
+and the normal `BukkitScheduler` everywhere else.
+
+---
+
+## Supported Versions
+
+Runs on Bukkit/Spigot/Paper/Folia from 1.13.2 through the year based drops: **26.1, 26.1.1, 26.1.2 and 26.2**.
+Minecraft dropped the leading `1.` in 2026, so the drop after 1.21.11 is 26.1, not 1.26.1.
+
+Builds against `spigot-api 26.2` and Java 21. `plugin.yml` keeps `api-version: 1.21` on purpose: it is a
+minimum, not a target, so the same jar still loads on 1.21 servers. To build against an older drop:
+
+```
+mvn -Dspigot.version=26.1-R0.1-SNAPSHOT clean package
+```
+
+---
 
 SignShop allows you to set up physical shops by punching a chest with your items you want to sell, then punching a sign (while holding redstone dust). It's easy to set up, and even easier to customize!
 

pom.xml

@@ -6,12 +6,15 @@
 
     <groupId>org.wargamer2010</groupId>
     <artifactId>SignShop</artifactId>
-    <version>5.2.0</version>
+    <version>5.2.3</version>
 
     <properties>
         <maven.compiler.source>21</maven.compiler.source>
         <maven.compiler.target>21</maven.compiler.target>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <!-- Newest game drop we build against. Override to check older ones still compile,
+             e.g. mvn -Dspigot.version=26.1-R0.1-SNAPSHOT compile -->
+        <spigot.version>26.2-R0.1-SNAPSHOT</spigot.version>
     </properties>
     <repositories>
         <repository>
@@ -55,114 +58,143 @@
         <dependency>
             <groupId>org.spigotmc</groupId>
             <artifactId>spigot-api</artifactId>
-            <version>1.21-R0.1-SNAPSHOT</version>
+            <version>${spigot.version}</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>org.jetbrains</groupId>
             <artifactId>annotations-java5</artifactId>
-            <version>24.0.1</version>
+            <version>24.1.0</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>com.github.MilkBowl</groupId>
             <artifactId>VaultAPI</artifactId>
-            <version>1.7</version>
+            <version>1.7.1</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>com.github.GriefPrevention</groupId>
             <artifactId>GriefPrevention</artifactId>
-            <version>16.18.4</version>
+            <version>18.0.0</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>com.sk89q.worldguard</groupId>
             <artifactId>worldguard-bukkit</artifactId>
-            <version>7.0.0</version>
+            <version>7.0.18</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>com.sk89q.worldedit</groupId>
             <artifactId>worldedit-bukkit</artifactId>
-            <version>7.1.0</version>
+            <version>7.4.5</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>com.palmergames.bukkit.towny</groupId>
             <artifactId>towny</artifactId>
-            <version>0.100.3.0</version>
+            <version>0.103.2.0</version>
+            <scope>provided</scope>
+        </dependency>
+        <!-- Towny is built against paper-api these days and its Resident/Town classes extend
+             Adventure audiences, so javac needs these interfaces on the classpath. We never
+             call them ourselves, which keeps the plugin running on plain Spigot. -->
+        <dependency>
+            <groupId>net.kyori</groupId>
+            <artifactId>adventure-api</artifactId>
+            <version>4.26.1</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>world.bentobox</groupId>
             <artifactId>bentobox</artifactId>
-            <version>2.4.1-SNAPSHOT</version>
+            <version>2.7.0</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
-            <groupId>com.bekvon.bukkit</groupId>
-            <artifactId>residence</artifactId>
-            <version>4.8.8.2</version>
+            <groupId>com.github.Zrips</groupId>
+            <artifactId>Residence</artifactId>
+            <version>6.0.2.3</version>
             <scope>provided</scope>
+            <optional>true</optional>
         </dependency>
         <dependency>
-            <groupId>com.earth2me</groupId>
-            <artifactId>essentials</artifactId>
-            <version>2.22.0</version>
+            <groupId>net.essentialsx</groupId>
+            <artifactId>EssentialsX</artifactId>
+            <version>2.21.2</version>
             <scope>provided</scope>
+            <optional>true</optional>
         </dependency>
         <dependency>
             <groupId>us.dynmap</groupId>
             <artifactId>DynmapCoreAPI</artifactId>
-            <version>3.7-beta-6</version>
+            <version>3.8</version>
             <scope>provided</scope>
+            <optional>true</optional>
         </dependency>
         <dependency>
             <groupId>org.xerial</groupId>
             <artifactId>sqlite-jdbc</artifactId>
-            <version>3.25.2</version>
+            <version>3.53.2.1</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
-            <groupId>com.Zrips</groupId>
+            <groupId>com.github.Zrips</groupId>
             <artifactId>CMI-API</artifactId>
-            <version>9.7.14.3</version>
+            <version>9.8.6.4</version>
             <scope>provided</scope>
+            <optional>true</optional>
         </dependency>
         <dependency>
             <groupId>com.griefcraft.lwc</groupId>
             <artifactId>LWCX</artifactId>
             <version>2.2.5</version>
             <scope>provided</scope>
+            <optional>true</optional>
         </dependency>
         <dependency>
             <groupId>nl.rutgerkok</groupId>
             <artifactId>blocklocker</artifactId>
-            <version>1.7</version>
+            <version>1.13</version>
             <scope>provided</scope>
+            <optional>true</optional>
         </dependency>
         <dependency>
             <groupId>com.github.angeschossen</groupId>
             <artifactId>LandsAPI</artifactId>
-            <version>4.9.4</version>
+            <version>7.25.4</version>
             <scope>provided</scope>
         </dependency>
         <dependency>
             <groupId>org.bstats</groupId>
             <artifactId>bstats-bukkit</artifactId>
-            <version>3.0.0</version>
+            <version>3.2.1</version>
             <scope>compile</scope>
         </dependency>
         <dependency>
             <groupId>com.google.code.gson</groupId>
             <artifactId>gson</artifactId>
-            <version>2.10.1</version>
+            <version>2.14.0</version>
             <scope>provided</scope>
         </dependency>
     </dependencies>
     <build>
         <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.11.0</version>
+                <configuration>
+                    <source>21</source>
+                    <target>21</target>
+                    <excludes>
+                        <!-- LWCX publishes no artifact we can resolve, so this hook is left out
+                             of the build. Everything else it hooks into is a real dependency. -->
+                        <exclude>**/hooks/LWCHook.java</exclude>
+                    </excludes>
+                </configuration>
+            </plugin>
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-jar-plugin</artifactId>

src/main/java/org/wargamer2010/signshop/SignShop.java

@@ -7,6 +7,7 @@
 import org.bukkit.command.CommandSender;
 import org.bukkit.configuration.file.FileConfiguration;
 import org.bukkit.event.Event;
+import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.PluginDescriptionFile;
 import org.bukkit.plugin.PluginManager;
 import org.bukkit.plugin.java.JavaPlugin;
@@ -273,11 +274,11 @@ public void onEnable() {
         }
         //Setup worth
         if (getSignShopConfig().getEnablePriceFromWorth()) {
-            if (Bukkit.getServer().getPluginManager().getPlugin("CMI") != null && Bukkit.getServer().getPluginManager().getPlugin("CMI").isEnabled()) {
+            if (isPluginRunning("CMI")) {
                 worthHandler = new CMIWorthHandler();
                 log("Using worth information from CMI.", Level.INFO);
             }
-            else if (Bukkit.getServer().getPluginManager().getPlugin("Essentials") != null && Bukkit.getServer().getPluginManager().getPlugin("Essentials").isEnabled()) {
+            else if (isPluginRunning("Essentials")) {
                 worthHandler = new EssentialsWorthHandler();
                 log("Using worth information from Essentials.", Level.INFO);
             }
@@ -309,6 +310,11 @@ else if (Bukkit.getServer().getPluginManager().getPlugin("Essentials") != null &
         log("v" + pdfFile.getVersion() + " Enabled", Level.INFO);
     }
 
+    private static boolean isPluginRunning(String name) {
+        Plugin plugin = Bukkit.getServer().getPluginManager().getPlugin(name);
+        return plugin != null && plugin.isEnabled();
+    }
+
     @Override
     public boolean onCommand(@NotNull CommandSender sender, @NotNull Command cmd, @NotNull String commandLabel, @NotNull String[] args) {
         String commandName = cmd.getName().toLowerCase();

src/main/java/org/wargamer2010/signshop/data/Storage.java

@@ -128,7 +128,9 @@ public static Storage init(File ymlFile) {
 
     public static void dispose() {
         instance = null;
-        fileSaveWorker.stop();
+        if (fileSaveWorker != null) {
+            fileSaveWorker.stop();
+        }
     }
 
     public static Storage get() {
@@ -225,8 +227,12 @@ private boolean loadSellerFromSettings(String key, HashMap<String,List<String>>
                 throw storageEx;
             }
             if(!itemUtil.clickedSign(seller_sign)) {
-                storageEx.setReason(StorageExceptionReason.SIGN_LOCATION_NOT_ACTUALLY_SIGN);
-                throw storageEx;
+                // On Folia, block checks during startup may fail due to threading
+                // Log a warning but continue loading - shop will be validated on first use
+                SignShop.log("Could not validate sign at " + seller_sign.getLocation() + " during startup (may be Folia threading issue). Will validate on first use.", java.util.logging.Level.WARNING);
+                // Don't throw exception - allow shop to load and be validated later
+                // storageEx.setReason(StorageExceptionReason.SIGN_LOCATION_NOT_ACTUALLY_SIGN);
+                // throw storageEx;
             }
             seller_activatables = signshopUtil.getBlocksFromLocStringList(getSetting(sellerSettings, "activatables"), world);
             seller_containables = signshopUtil.getBlocksFromLocStringList(getSetting(sellerSettings, "containables"), world);

src/main/java/org/wargamer2010/signshop/data/serialization/BukkitSerialization.java

@@ -6,11 +6,11 @@
 import org.bukkit.inventory.PlayerInventory;
 import org.bukkit.util.io.BukkitObjectInputStream;
 import org.bukkit.util.io.BukkitObjectOutputStream;
-import org.yaml.snakeyaml.external.biz.base64Coder.Base64Coder;
 
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
+import java.util.Base64;
 
 /**
  * Legacy Java object serialization for ItemStacks.
@@ -23,10 +23,29 @@
  * @see ItemSerializer
  */
 public class BukkitSerialization {
+    /**
+     * SnakeYAML 2.6 (shipped with Minecraft 26.1 and up) dropped its bundled Base64Coder,
+     * so we encode ourselves. Same layout as before: 76 character lines separated by the
+     * platform line ending, and a lenient decoder so shops written by older builds
+     * (or on Windows, with CRLF) still load.
+     */
+    private static final Base64.Encoder ENCODER =
+            Base64.getMimeEncoder(76, System.lineSeparator().getBytes());
+    private static final Base64.Decoder DECODER = Base64.getMimeDecoder();
+
     private BukkitSerialization() {
 
     }
 
+    /**
+     * Base64 encodes the given bytes the way snakeyaml used to: 76 character lines, and a line
+     * break after the last one as well, so re-saving a shop leaves the file byte for byte the same.
+     */
+    private static String encodeBase64(byte[] data) {
+        String encoded = ENCODER.encodeToString(data);
+        return encoded.isEmpty() ? encoded : encoded + System.lineSeparator();
+    }
+
     /**
      * Converts the player inventory to a String array of Base64 strings. First string is the content and second string is the armor.
      *
@@ -68,7 +87,7 @@ public static String itemStackArrayToBase64(ItemStack[] items) throws IllegalSta
 
             // Serialize that array
             dataOutput.close();
-            return Base64Coder.encodeLines(outputStream.toByteArray());
+            return encodeBase64(outputStream.toByteArray());
         } catch (Exception e) {
             throw new IllegalStateException("Unable to save item stacks.", e);
         }
@@ -99,7 +118,7 @@ public static String toBase64(Inventory inventory) throws IllegalStateException
 
             // Serialize that array
             dataOutput.close();
-            return Base64Coder.encodeLines(outputStream.toByteArray());
+            return encodeBase64(outputStream.toByteArray());
         } catch (Exception e) {
             throw new IllegalStateException("Unable to save item stacks.", e);
         }
@@ -117,7 +136,7 @@ public static String toBase64(Inventory inventory) throws IllegalStateException
      */
     public static Inventory fromBase64(String data) throws IOException {
         try {
-            ByteArrayInputStream inputStream = new ByteArrayInputStream(Base64Coder.decodeLines(data));
+            ByteArrayInputStream inputStream = new ByteArrayInputStream(DECODER.decode(data));
             BukkitObjectInputStream dataInput = new BukkitObjectInputStream(inputStream);
             Inventory inventory = Bukkit.getServer().createInventory(null, dataInput.readInt());
 
@@ -142,7 +161,7 @@ public static Inventory fromBase64(String data) throws IOException {
      */
     public static ItemStack[] itemStackArrayFromBase64(String data) throws IOException {
     	try {
-            ByteArrayInputStream inputStream = new ByteArrayInputStream(Base64Coder.decodeLines(data));
+            ByteArrayInputStream inputStream = new ByteArrayInputStream(DECODER.decode(data));
             BukkitObjectInputStream dataInput = new BukkitObjectInputStream(inputStream);
             ItemStack[] items = new ItemStack[dataInput.readInt()];
 

src/main/java/org/wargamer2010/signshop/incompatibility/IncompatibilityDetector.java

@@ -31,8 +31,7 @@
  *
  *     {@literal @}Override
  *     public boolean isRelevantForCurrentVersion() {
- *         String version = Bukkit.getVersion();
- *         return version.contains("1.21.10") || version.contains("1.21.1");
+ *         return versionUtil.isAtLeast("1.21.10");
  *     }
  *
  *     {@literal @}Override
@@ -70,12 +69,16 @@ public interface IncompatibilityDetector {
      * <p>This allows detectors to be automatically disabled if running on a Spigot
      * version where the incompatibility doesn't exist (e.g., if Spigot fixes the bug).</p>
      *
+     * <p>Compare with {@link org.wargamer2010.signshop.util.versionUtil#isAtLeast(String)} instead
+     * of matching on the version string. Minecraft switched from 1.x to a year based scheme
+     * (26.1, 26.1.1, 26.1.2, 26.2, ...), so a check like {@code version.contains("1.21")} quietly
+     * stops matching on newer servers.</p>
+     *
      * <p><b>Example:</b></p>
      * <pre>
      * public boolean isRelevantForCurrentVersion() {
-     *     String version = Bukkit.getVersion();
-     *     // Only relevant for Spigot 1.21.10 through 1.21.19
-     *     return version.contains("1.21.1") && !version.contains("1.21.2");
+     *     // 1.21.10 up to, but not including, 26.2
+     *     return versionUtil.isAtLeast("1.21.10") {@literal &&} !versionUtil.isAtLeast("26.2");
      * }
      * </pre>
      *