Implement basic tab-completion

src/main/java/wtf/beatrice/nounspicker/NounsPicker.java

@@ -5,6 +5,7 @@ import org.bukkit.plugin.PluginManager;
 import org.bukkit.plugin.java.JavaPlugin;
 import wtf.beatrice.nounspicker.commands.NounsCommand;
 import wtf.beatrice.nounspicker.objects.PAPIManager;
+import wtf.beatrice.nounspicker.objects.TabCompletion;
 import wtf.beatrice.nounspicker.utils.Cache;
 import wtf.beatrice.nounspicker.utils.ConsoleLogger;
 import wtf.beatrice.nounspicker.utils.DatabaseManager;
@@ -39,6 +40,7 @@ public class NounsPicker extends JavaPlugin
 
         logger.log("Registering commands...");
         getCommand("nouns").setExecutor(new NounsCommand(this));
+        getCommand("nouns").setTabCompleter(new TabCompletion());
         logger.log("Commands registered!");
 
         logger.log("Checking files...");

src/main/java/wtf/beatrice/nounspicker/objects/TabCompletion.java

@@ -0,0 +1,37 @@
+package wtf.beatrice.nounspicker.objects;
+
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandSender;
+import org.bukkit.util.StringUtil;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class TabCompletion implements org.bukkit.command.TabCompleter
+{
+
+    private final List<String> mainSubCommands = new ArrayList<>(){{
+        add("set");
+        add("create");
+        add("delete");
+        add("update");
+    }};
+
+    @Override
+    public List<String> onTabComplete(CommandSender sender, Command command, String label, String[] args) {
+        List<String> completions = new ArrayList<>();
+
+        if(args.length == 0) return null;
+
+        String mainArg = args[0].toLowerCase();
+        if(args.length == 1)
+        {
+            StringUtil.copyPartialMatches(mainArg, mainSubCommands, completions);
+        }
+
+
+
+        return completions;
+    }
+
+}

src/main/java/wtf/beatrice/nounspicker/utils/Cache.java

@@ -3,10 +3,14 @@ package wtf.beatrice.nounspicker.utils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.List;
 
 public class Cache
 {
 
     public static DatabaseManager dbManager;
+
+    public static List<String> pronouns = new ArrayList<>();
 }

src/main/java/wtf/beatrice/nounspicker/utils/DatabaseManager.java

@@ -146,6 +146,11 @@ public class DatabaseManager
             pStatement.setString(2, format);
             pStatement.setInt(3, pronounId);
             pStatement.executeUpdate();
+
+            // add to cache
+            Cache.pronouns.add(pronoun);
+
+            // announce success
             return true;
         } catch (SQLException e)
         {
@@ -209,6 +214,9 @@ public class DatabaseManager
             }
         }
 
+        // remove from cache
+        Cache.pronouns.remove(pronoun);
+
         // announce success
         return true;
     }