Updated a bunch of framework, removed useless functions and fixed possible N(2o) complexity issue.

src/main/java/io/github/paldiu/simplexcore/command/CommandInfo.java

@@ -1,9 +1,12 @@
 package io.github.paldiu.simplexcore.command;
 
+import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 
 @Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.TYPE)
 public @interface CommandInfo {
     String name();
 

src/main/java/io/github/paldiu/simplexcore/command/SimplexCommand.java

@@ -2,6 +2,7 @@ package io.github.paldiu.simplexcore.command;
 
 import io.github.paldiu.simplexcore.utils.Constants;
 import io.github.paldiu.simplexcore.utils.Utilities;
+import jdk.jfr.BooleanFlag;
 import org.bukkit.command.Command;
 import org.bukkit.command.CommandExecutor;
 import org.bukkit.command.CommandSender;
@@ -15,7 +16,8 @@ import java.util.List;
 import java.util.UUID;
 
 public abstract class SimplexCommand implements CommandExecutor, TabCompleter {
-    public boolean checkSender(CommandSender sender) {
+    @BooleanFlag
+    public boolean isPlayer(CommandSender sender) {
         return sender instanceof Player;
     }
 
@@ -29,12 +31,23 @@ public abstract class SimplexCommand implements CommandExecutor, TabCompleter {
         return Constants.getServer().getPlayer(uuid);
     }
 
-    public void playerMsg(Player player, String... message) {
+    @Nullable
+    public Player getPlayer(CommandSender sender) {
+        return isPlayer(sender) ? (Player)sender : null;
+    }
+
+    public void playerMsg(Player player, String... messages) {
         StringBuilder builder = new StringBuilder();
-        Utilities.primitiveFE(message, builder::append);
+        Utilities.forEach(messages, builder::append);
         player.sendMessage(builder.toString());
     }
 
+    public void msg(CommandSender sender, String... messages) {
+        StringBuilder builder = new StringBuilder();
+        Utilities.forEach(messages, builder::append);
+        sender.sendMessage(builder.toString());
+    }
+
     @Nullable
     @Override
     public List<String> onTabComplete(@NotNull CommandSender sender, @NotNull Command command, @NotNull String alias, @NotNull String[] args) {

src/main/java/io/github/paldiu/simplexcore/utils/Constants.java

@@ -14,6 +14,11 @@ import org.bukkit.scheduler.BukkitScheduler;
 import java.util.logging.Logger;
 
 public final class Constants {
+    // Utility class should not be instantiated.
+    private Constants() {
+        throw new AssertionError();
+    }
+
     private static final SimplexCore plugin = JavaPlugin.getPlugin(SimplexCore.class);
     private static final Server server = plugin.getServer();
     private static final Logger logger = plugin.getLogger();

src/main/java/io/github/paldiu/simplexcore/utils/Utilities.java

@@ -11,36 +11,58 @@ import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
 public final class Utilities {
-    private static <T> Stream<T> feStr(T[] array) {
-        return Arrays.stream(array);
+    //Utility class should not be instantiated.
+    private Utilities() {
+        throw new AssertionError();
     }
 
-    private static <T> Set<T> feCol(Stream<T> stream) {
-        return stream.collect(Collectors.toSet());
-    }
-
-    public static <T> void primitiveFE(T[] array, Consumer<? super T> action) {
-        feCol(feStr(array)).forEach(action);
-    }
-
-    public static <T> void smartFE(Collection<T> collection, Consumer<? super T> action) {
-        collection.forEach(action);
-    }
-
-    public static <K, V> void mapFE(Map<K, V> map, BiConsumer<K, V> actions) {
-        map.forEach(actions);
+    public static <T> void forEach(T[] array, Consumer<? super T> action) {
+        for (T obj : array) {
+            action.accept(obj);
+        }
     }
 
     public static String generateBanId(BanType type) {
-        String charList = "AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz";
-        int length = charList.length();
+        final String charList = "AaBbCcDdEeFfGgHhIiJjKkLlMmNnOoPpQqRrSsTtUuVvWwXxYyZz";
+        final String numList = "0123456789";
+        final int length = charList.length();
+        final int lng = numList.length();
 
-        StringBuilder sb = new StringBuilder();
-        SplittableRandom random = new SplittableRandom();
+        final StringBuilder sb = new StringBuilder();
 
-        for (int x = 0; x <= 8; x++) {
-            sb.append(charList.indexOf(random.nextInt(length - 1)));
+        sb.append(type.getPrefix());
+
+        for (int x = 0; x < 4; x++) {
+            sb.append(charList.charAt(random.nextInt(length - 1)));
+            sb.append(numList.charAt(numbers.nextInt(lng - 1)));
         }
+
+        sb.setCharAt(2, capitalize(sb.charAt(2)));
         return sb.toString();
     }
+
+    private static final SplittableRandom random = new SplittableRandom();
+    private static final SplittableRandom numbers = new SplittableRandom();
+    private static final List<Character> list = new ArrayList<>(){{
+        add('0');
+        add('1');
+        add('2');
+        add('3');
+        add('4');
+        add('5');
+        add('6');
+        add('7');
+        add('8');
+        add('9');
+        add('-');
+    }};
+
+    private static char capitalize(char character) {
+        if (list.contains(character)) {
+            return character;
+        }
+
+        String temp = String.valueOf(character).toUpperCase();
+        return temp.charAt(0);
+    }
 }

src/test/java/io/github/paldiu/simplexcore/utils/UtilitiesTest.java

@@ -0,0 +1,10 @@
+package io.github.paldiu.simplexcore.utils;
+
+import junit.framework.TestCase;
+import io.github.paldiu.simplexcore.banning.BanType;
+
+public class UtilitiesTest extends TestCase {
+    public void testGenerateBanId() {
+        System.out.println(Utilities.generateBanId(BanType.TEMPORARY));
+    }
+}