Use reflection to use sun.misc.Unsafe

README.md

@@ -1,22 +1,22 @@
 # FastBoard
 [![Java CI](https://github.com/MrMicky-FR/FastBoard/actions/workflows/build.yml/badge.svg)](https://github.com/MrMicky-FR/FastBoard/actions/workflows/build.yml)
-[![Sonatype Snapshots](https://img.shields.io/nexus/s/fr.mrmicky/fastboard?label=sonatype%20snapshots&server=https%3A%2F%2Fs01.oss.sonatype.org)](pom.xml)
-[![Discord](https://img.shields.io/discord/390919659874156560.svg?colorB=7289da&label=discord&logo=discord&logoColor=white)](https://discord.gg/q9UwaBT)
+[![Sonatype Snapshots](https://img.shields.io/nexus/s/fr.mrmicky/fastboard?label=Sonatype%20snapshots&server=https%3A%2F%2Fs01.oss.sonatype.org)](pom.xml)
+[![Discord](https://img.shields.io/discord/390919659874156560.svg?colorB=5865f2&label=Discord&logo=discord&logoColor=white)](https://discord.gg/q9UwaBT)
 
-Lightweight packet-based scoreboard API for Bukkit plugins, with 1.7.10 to 1.16 support.
+Lightweight packet-based scoreboard API for Bukkit plugins, with 1.7.10 to 1.17 support.
 
 ⚠️ To use FastBoard on a 1.8 server, the server must be on 1.8.8.
 
 ## Features
 
 * No flickering (without using a buffer)
-* Works with all versions from 1.7.10 to 1.16
-* Very small (around 550 lines of code with the JavaDoc) and no dependencies
+* Works with all versions from 1.7.10 to 1.17
+* Very small (around 600 lines of code with the JavaDoc) and no dependencies
 * Easy to use
 * Dynamic scoreboard size: you don't need to add/remove lines, you can just give a string list (or array) to change all the lines
 * Everything is at packet level, so it works with other plugins using scoreboard and/or teams
-* Can be used in an async thread
-* Supports up to 30 characters per line on 1.7-1.12
+* Can be used asynchronously
+* Supports up to 30 characters per line on 1.12.2 and below
 * No character limit on 1.13 and higher
 * Supports hex colors on 1.16 and higher
 
@@ -50,17 +50,15 @@ Lightweight packet-based scoreboard API for Bukkit plugins, with 1.7.10 to 1.16
         </plugin>
     </plugins>
 </build>
-```
-```xml
+
 <dependencies>
     <dependency>
         <groupId>fr.mrmicky</groupId>
         <artifactId>fastboard</artifactId>
         <version>1.2.0-SNAPSHOT</version>
     </dependency>
 </dependencies>
-```
-```xml
+
 <repositories>
     <repository>
         <id>sonatype-oss</id>
@@ -75,18 +73,15 @@ Lightweight packet-based scoreboard API for Bukkit plugins, with 1.7.10 to 1.16
 plugins {
     id 'com.github.johnrengelman.shadow' version '6.1.0'
 }
-```
-```groovy
+
 repositories {
     maven { url 'https://s01.oss.sonatype.org/content/repositories/snapshots/' }
 }
-```
-```groovy
+
 dependencies {
     implementation 'fr.mrmicky:fastboard:1.2.0-SNAPSHOT'
 }
-```
-```groovy
+
 shadowJar {
     // Replace 'com.yourpackage' with the package of your plugin 
     relocate 'fr.mrmicky.fastboard', 'com.yourpackage.fastboard'
@@ -95,13 +90,13 @@ shadowJar {
 
 ### Manual
 
-Copy `FastBoard.java` and `FastReflection.java` in your plugin
+Copy `FastBoard.java` and `FastReflection.java` in your plugin.
 
 ## Usage
 
 ### Creating a scoreboard
 
-Just create a new `FastBoard` and update the title and the lines
+Just create a new `FastBoard` and update the title and the lines:
 
 ```java
 FastBoard board = new FastBoard(player);
@@ -113,7 +108,7 @@ board.updateTitle(ChatColor.GOLD + "FastBoard");
 board.updateLines(
         "", // Empty line
         "One line",
-        "", // Empty line
+        "",
         "Second line"
 );
 ```

src/main/java/fr/mrmicky/fastboard/FastBoard.java

@@ -45,7 +45,7 @@
 
 /**
  * Lightweight packet-based scoreboard API for Bukkit plugins.
- * It can be used safely in an async thread as everything is at packet level.
+ * It can be safely used asynchronously as everything is at packet level.
  * <p>
  * The project is on <a href="https://github.com/MrMicky-FR/FastBoard">GitHub</a>.
  *
@@ -55,6 +55,9 @@
 public class FastBoard {
 
     private static final Map<Class<?>, Field[]> PACKETS = new HashMap<>(8);
+    private static final String[] COLOR_CODES = Arrays.stream(ChatColor.values())
+            .map(Object::toString)
+            .toArray(String[]::new);
     private static final VersionType VERSION_TYPE;
     // Packets and components
     private static final Class<?> CHAT_COMPONENT_CLASS;
@@ -433,15 +436,11 @@ private void checkLineNumber(int line, boolean checkInRange, boolean checkMax) {
             throw new IllegalArgumentException("Line number must be under " + this.lines.size());
         }
 
-        if (checkMax && line >= ChatColor.values().length - 1) {
+        if (checkMax && line >= COLOR_CODES.length - 1) {
             throw new IllegalArgumentException("Line number is too high: " + this.lines.size());
         }
     }
 
-    private String getColorCode(int score) {
-        return ChatColor.values()[score].toString();
-    }
-
     private int getScoreByLine(int line) {
         return this.lines.size() - line - 1;
     }
@@ -485,7 +484,7 @@ private void sendDisplayObjectivePacket() throws Throwable {
     private void sendScorePacket(int score, ScoreboardAction action) throws Throwable {
         Object packet = PACKET_SB_SCORE.invoke();
 
-        setField(packet, String.class, getColorCode(score), 0); // Player Name
+        setField(packet, String.class, COLOR_CODES[score], 0); // Player Name
 
         if (VersionType.V1_8.isHigherOrEqual()) {
             setField(packet, ENUM_SB_ACTION, action == ScoreboardAction.REMOVE ? ENUM_SB_ACTION_REMOVE : ENUM_SB_ACTION_CHANGE);
@@ -518,7 +517,7 @@ private void sendTeamPacket(int score, TeamMode mode) throws Throwable {
             String suffix = null;
 
             if (line == null || line.isEmpty()) {
-                prefix = getColorCode(score) + ChatColor.RESET;
+                prefix = COLOR_CODES[score] + ChatColor.RESET;
             } else if (line.length() <= maxLength) {
                 prefix = line;
             } else {
@@ -562,7 +561,7 @@ private void sendTeamPacket(int score, TeamMode mode) throws Throwable {
             }
 
             if (mode == TeamMode.CREATE) {
-                setField(packet, Collection.class, Collections.singletonList(getColorCode(score))); // Players in the team
+                setField(packet, Collection.class, Collections.singletonList(COLOR_CODES[score])); // Players in the team
             }
         }
 

src/main/java/fr/mrmicky/fastboard/FastReflection.java

@@ -23,17 +23,15 @@
  */
 package fr.mrmicky.fastboard;
 
-import com.google.common.base.Suppliers;
 import org.bukkit.Bukkit;
-import sun.misc.Unsafe;
 
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.lang.invoke.MethodType;
 import java.lang.reflect.Field;
+import java.lang.reflect.Method;
 import java.util.Optional;
 import java.util.function.Predicate;
-import java.util.function.Supplier;
 
 /**
  * Small reflection utility class to use CraftBukkit and NMS.
@@ -42,7 +40,7 @@
  */
 public final class FastReflection {
 
-    public static final String NM_PACKAGE = "net.minecraft";
+    private static final String NM_PACKAGE = "net.minecraft";
     public static final String OBC_PACKAGE = "org.bukkit.craftbukkit";
     public static final String NMS_PACKAGE = NM_PACKAGE + ".server";
 
@@ -51,15 +49,7 @@ public final class FastReflection {
     private static final MethodType VOID_METHOD_TYPE = MethodType.methodType(void.class);
     private static final boolean NMS_REPACKAGED = optionalClass(NM_PACKAGE + ".network.protocol.Packet").isPresent();
 
-    private static final Supplier<Unsafe> UNSAFE = Suppliers.memoize(() -> {
-        try {
-            Field f = Unsafe.class.getDeclaredField("theUnsafe");
-            f.setAccessible(true);
-            return (Unsafe) f.get(null);
-        } catch (NoSuchFieldException | IllegalAccessException e) {
-            throw new RuntimeException(e);
-        }
-    });
+    private static volatile Object theUnsafe;
 
     private FastReflection() {
         throw new UnsupportedOperationException();
@@ -130,14 +120,27 @@ static Class<?> innerClass(Class<?> parentClass, Predicate<Class<?>> classPredic
         throw new ClassNotFoundException("No class in " + parentClass.getCanonicalName() + " matches the predicate.");
     }
 
-    public static PacketConstructor findPacketConstructor(Class<?> packetClass, MethodHandles.Lookup lookup) {
+    public static PacketConstructor findPacketConstructor(Class<?> packetClass, MethodHandles.Lookup lookup) throws Exception {
         try {
             MethodHandle constructor = lookup.findConstructor(packetClass, VOID_METHOD_TYPE);
             return constructor::invoke;
         } catch (NoSuchMethodException | IllegalAccessException e) {
-            Unsafe unsafe = UNSAFE.get();
-            return () -> unsafe.allocateInstance(packetClass);
+            // try below with Unsafe
+        }
+
+        if (theUnsafe == null) {
+            synchronized (FastReflection.class) {
+                if (theUnsafe == null) {
+                    Class<?> unsafeClass = Class.forName("sun.misc.Unsafe");
+                    Field theUnsafeField = unsafeClass.getDeclaredField("theUnsafe");
+                    theUnsafeField.setAccessible(true);
+                    theUnsafe = theUnsafeField.get(null);
+                }
+            }
         }
+
+        Method allocateMethod = theUnsafe.getClass().getMethod("allocateInstance", Class.class);
+        return () -> allocateMethod.invoke(theUnsafe, packetClass);
     }
 
     @FunctionalInterface