Fix rare NPE for gson.fromJson in PlayerHandler

core/src/main/java/ch/andre601/advancedserverlist/core/profiles/players/PlayerHandler.java

@@ -31,30 +31,28 @@
 import com.google.gson.Gson;
 import io.leangen.geantyref.TypeToken;
 
+import java.io.BufferedReader;
 import java.io.BufferedWriter;
 import java.io.IOException;
-import java.io.Reader;
 import java.lang.reflect.Type;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.UUID;
+import java.util.*;
 
 public class PlayerHandler{
 
     private final AdvancedServerList<?> core;
     private final PluginLogger logger;
     private final Path cache;
-    private List<CachedPlayer> cachedPlayers = new ArrayList<>();
 
     private final Type listType = new TypeToken<ArrayList<CachedPlayer>>(){}.getType();
     private final Gson gson = new Gson();
 
     // UUID of MHF_Question
     private final UUID defaultUUID = UUID.fromString("606e2ff0-ed77-4842-9d6c-e1d3321c7838");
 
+    private List<CachedPlayer> cachedPlayers = new ArrayList<>();
     private CachedPlayer defaultPlayer = null;
 
     public PlayerHandler(AdvancedServerList<?> core){
@@ -75,7 +73,7 @@ public void load(){
         }
 
         try{
-            Reader reader = Files.newBufferedReader(cache);
+            BufferedReader reader = Files.newBufferedReader(cache);
 
             cachedPlayers = gson.fromJson(reader, listType);
 
@@ -85,6 +83,14 @@ public void load(){
             return;
         }
 
+        // In case Gson messes up... I guess.
+        if(cachedPlayers == null){
+            logger.warn("Couldn't load players from playercache.json file. Is the JSON valid?");
+            // Create new ArrayList instance to avoid further issues.
+            cachedPlayers = new ArrayList<>();
+            return;
+        }
+
         logger.info("Loaded %d players into cache!", cachedPlayers.size());
     }
 

pom.xml

@@ -38,7 +38,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.build.commit/>
 
-        <plugin.version>3.2.0</plugin.version>
+        <plugin.version>3.2.1</plugin.version>
         <plugin.description>Create multiple Server lists based on conditions.</plugin.description>
 
         <api.version>v3.0.0</api.version>