Added support for getOfflinePlayer(String) with optional cache

src/main/java/io/papermc/lib/PaperLib.java

@@ -1,23 +1,27 @@
 package io.papermc.lib;
 
-import io.papermc.lib.environments.CraftBukkitEnvironment;
-import io.papermc.lib.environments.Environment;
-import io.papermc.lib.environments.PaperEnvironment;
-import io.papermc.lib.environments.SpigotEnvironment;
-import io.papermc.lib.features.blockstatesnapshot.BlockStateSnapshotResult;
+import java.util.concurrent.CompletableFuture;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 import org.bukkit.Chunk;
 import org.bukkit.Location;
+import org.bukkit.OfflinePlayer;
 import org.bukkit.World;
 import org.bukkit.block.Block;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.Player;
 import org.bukkit.event.player.PlayerTeleportEvent.TeleportCause;
 import org.bukkit.plugin.Plugin;
 
-import javax.annotation.Nonnull;
-import java.util.concurrent.CompletableFuture;
-import java.util.logging.Level;
-import java.util.logging.Logger;
+import io.papermc.lib.environments.CraftBukkitEnvironment;
+import io.papermc.lib.environments.Environment;
+import io.papermc.lib.environments.PaperEnvironment;
+import io.papermc.lib.environments.SpigotEnvironment;
+import io.papermc.lib.features.blockstatesnapshot.BlockStateSnapshotResult;
 
 /**
  * Utility methods that assist plugin developers accessing Paper features.
@@ -201,6 +205,18 @@ public static BlockStateSnapshotResult getBlockState(@Nonnull Block block, boole
     public static CompletableFuture<Location> getBedSpawnLocationAsync(@Nonnull Player player, boolean isUrgent) {
         return ENVIRONMENT.getBedSpawnLocationAsync(player, isUrgent);
     }
+
+    /**
+     * Gets an OfflinePlayer by the given name. If the Player is not cached, an optional web request
+     * can be made to look up the UUID of that player. Web requests will block the current Thread though.
+     * @param name           The name of this OfflinePlayer.
+     * @param makeWebRequest Whether or not a web request for UUID lookups should be made.
+     * @return OfflinePlayer by the given name or null if the player is not cached and no web request was made.
+     */
+    @Nullable
+    public static OfflinePlayer getOfflinePlayer(@Nonnull String name, boolean makeWebRequest) {
+        return ENVIRONMENT.getOfflinePlayer(name, makeWebRequest);
+    }
 
     /**
      * Detects if the current MC version is at least the following version.

src/main/java/io/papermc/lib/environments/Environment.java

@@ -13,21 +13,27 @@
 import io.papermc.lib.features.chunkisgenerated.ChunkIsGenerated;
 import io.papermc.lib.features.chunkisgenerated.ChunkIsGeneratedApiExists;
 import io.papermc.lib.features.chunkisgenerated.ChunkIsGeneratedUnknown;
+import io.papermc.lib.features.offlineplayers.GetOfflinePlayer;
+import io.papermc.lib.features.offlineplayers.GetOfflinePlayerSpigot;
+
 import org.bukkit.Bukkit;
 import org.bukkit.Chunk;
 import org.bukkit.Location;
+import org.bukkit.OfflinePlayer;
 import org.bukkit.World;
 import org.bukkit.block.Block;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.Player;
 import org.bukkit.event.player.PlayerTeleportEvent.TeleportCause;
 
-import javax.annotation.Nonnull;
 import java.util.concurrent.CompletableFuture;
 import java.util.regex.MatchResult;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
 @SuppressWarnings("WeakerAccess")
 public abstract class Environment {
 
@@ -40,6 +46,7 @@ public abstract class Environment {
     protected ChunkIsGenerated isGeneratedHandler = new ChunkIsGeneratedUnknown();
     protected BlockStateSnapshot blockStateSnapshotHandler;
     protected BedSpawnLocation bedSpawnLocationHandler = new BedSpawnLocationSync();
+    protected GetOfflinePlayer getOfflinePlayerHandler = new GetOfflinePlayerSpigot();
 
     public Environment() {
         Pattern versionPattern = Pattern.compile("\\(MC: (\\d)\\.(\\d+)\\.?(\\d+?)?(?: Pre-Release )?(\\d)?\\)");
@@ -112,6 +119,11 @@ public BlockStateSnapshotResult getBlockState(Block block, boolean useSnapshot)
     public CompletableFuture<Location> getBedSpawnLocationAsync(Player player, boolean isUrgent) {
         return bedSpawnLocationHandler.getBedSpawnLocationAsync(player, isUrgent);
     }
+
+    @Nullable
+    public OfflinePlayer getOfflinePlayer(@Nonnull String name, boolean makeWebRequest) {
+        return getOfflinePlayerHandler.getOfflinePlayer(name, makeWebRequest);
+    }
 
     public boolean isVersion(int minor) {
         return isVersion(minor, 0);

src/main/java/io/papermc/lib/environments/PaperEnvironment.java

@@ -8,7 +8,10 @@
 import io.papermc.lib.features.bedspawnlocation.BedSpawnLocationPaper;
 import io.papermc.lib.features.blockstatesnapshot.BlockStateSnapshotOptionalSnapshots;
 import io.papermc.lib.features.chunkisgenerated.ChunkIsGeneratedApiExists;
+import io.papermc.lib.features.offlineplayers.GetOfflinePlayerPaper;
+
 import org.bukkit.Location;
+import org.bukkit.Server;
 import org.bukkit.World;
 import org.bukkit.entity.HumanEntity;
 
@@ -38,6 +41,13 @@ public PaperEnvironment() {
                 bedSpawnLocationHandler = new BedSpawnLocationPaper();
             } catch (NoSuchMethodException ignored) {}
         }
+        if (isVersion(16, 4)) {
+            try {
+                // Check for the new "getOfflinePlayerIfCached" method which was added in Paper API 1.16.4+
+                Server.class.getDeclaredMethod("getOfflinePlayerIfCached", String.class);
+                getOfflinePlayerHandler = new GetOfflinePlayerPaper();
+            } catch(NoSuchMethodException ignored) {}
+        }
     }
 
     @Override

src/main/java/io/papermc/lib/features/offlineplayers/GetOfflinePlayer.java

@@ -0,0 +1,11 @@
+package io.papermc.lib.features.offlineplayers;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+import org.bukkit.OfflinePlayer;
+
+public interface GetOfflinePlayer {
+    @Nullable
+    OfflinePlayer getOfflinePlayer(@Nonnull String name, boolean makeWebRequest);
+}

src/main/java/io/papermc/lib/features/offlineplayers/GetOfflinePlayerPaper.java

@@ -0,0 +1,19 @@
+package io.papermc.lib.features.offlineplayers;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+import org.bukkit.Bukkit;
+import org.bukkit.OfflinePlayer;
+
+public class GetOfflinePlayerPaper implements GetOfflinePlayer {
+    @Override
+    @Nullable
+    public OfflinePlayer getOfflinePlayer(@Nonnull String name, boolean makeWebRequest) {
+        if (makeWebRequest) {
+            return Bukkit.getOfflinePlayer(name);
+        } else {
+            return Bukkit.getOfflinePlayerIfCached(name);
+        }
+    }
+}

src/main/java/io/papermc/lib/features/offlineplayers/GetOfflinePlayerSpigot.java

@@ -0,0 +1,15 @@
+package io.papermc.lib.features.offlineplayers;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+
+import org.bukkit.Bukkit;
+import org.bukkit.OfflinePlayer;
+
+public class GetOfflinePlayerSpigot implements GetOfflinePlayer {
+    @Override
+    @Nullable
+    public OfflinePlayer getOfflinePlayer(@Nonnull String name, boolean makeWebRequest) {
+        return Bukkit.getOfflinePlayer(name);
+    }
+}