Fix most checkstyle warnings

src/main/java/net/minestom/server/entity/Entity.java

@@ -404,7 +404,8 @@ public abstract class Entity implements Viewable, EventHandler, DataContainer, P
 
         // remove expired effects
         {
-            effects.removeIf(timedPotion -> time >=
+            effects.removeIf(timedPotion -> time
+                    >=
                     (timedPotion.getStartingTime() + timedPotion.getPotion().getDuration() * MinecraftServer.TICK_MS));
         }
 
@@ -1474,7 +1475,7 @@ public abstract class Entity implements Viewable, EventHandler, DataContainer, P
     }
 
     /**
-     * Adds an effect to an entity
+     * Adds an effect to an entity.
      *
      * @param potion The potion to add
      */

src/main/java/net/minestom/server/potion/Potion.java

@@ -1,7 +1,6 @@
 package net.minestom.server.potion;
 
 import net.minestom.server.entity.Entity;
-import net.minestom.server.entity.Player;
 import net.minestom.server.network.packet.server.play.EntityEffectPacket;
 import net.minestom.server.network.packet.server.play.RemoveEntityEffectPacket;
 import org.jetbrains.annotations.NotNull;
@@ -12,26 +11,66 @@ public class Potion {
     private final int duration;
     private final byte flags;
 
+    /**
+     * Creates a new potion.
+     *
+     * @param effect The type of potion.
+     * @param amplifier The strength of the potion.
+     * @param duration The length of the potion in ticks.
+     */
     public Potion(PotionEffect effect, byte amplifier, int duration) {
         this(effect, amplifier, duration, true, true, false);
     }
 
+    /**
+     * Creates a new potion.
+     *
+     * @param effect The type of potion.
+     * @param amplifier The strength of the potion.
+     * @param duration The length of the potion in ticks.
+     * @param particles If the potion has particles.
+     */
     public Potion(PotionEffect effect, byte amplifier, int duration, boolean particles) {
         this(effect, amplifier, duration, particles, true, false);
     }
 
+    /**
+     * Creates a new potion.
+     *
+     * @param effect The type of potion.
+     * @param amplifier The strength of the potion.
+     * @param duration The length of the potion in ticks.
+     * @param particles If the potion has particles.
+     * @param icon If the potion has an icon.
+     */
     public Potion(PotionEffect effect, byte amplifier, int duration, boolean particles, boolean icon) {
         this(effect, amplifier, duration, particles, icon, false);
     }
 
+    /**
+     * Creates a new potion.
+     *
+     * @param effect The type of potion.
+     * @param amplifier The strength of the potion.
+     * @param duration The length of the potion in ticks.
+     * @param particles If the potion has particles.
+     * @param icon If the potion has an icon.
+     * @param ambient If the potion came from a beacon.
+     */
     public Potion(PotionEffect effect, byte amplifier, int duration, boolean particles, boolean icon, boolean ambient) {
         this.effect = effect;
         this.amplifier = amplifier;
         this.duration = duration;
         byte flags = 0;
-        if (ambient) flags = (byte)(flags | 0x01);
+        if (ambient) {
-        if (particles) flags = (byte)(flags | 0x02);
+            flags = (byte) (flags | 0x01);
-        if (icon) flags = (byte)(flags | 0x04);
+        }
+        if (particles) {
+            flags = (byte) (flags | 0x02);
+        }
+        if (icon) {
+            flags = (byte) (flags | 0x04);
+        }
         this.flags = flags;
     }
 
@@ -51,6 +90,12 @@ public class Potion {
         return flags;
     }
 
+    /**
+     * Sends a packet that a potion effect has been applied to the entity.
+     * <p>
+     * Used internally by {@link net.minestom.server.entity.Player#addEffect(Potion)}
+     * @param entity
+     */
     public void sendAddPacket(@NotNull Entity entity) {
         EntityEffectPacket eep = new EntityEffectPacket();
         eep.entityId = entity.getEntityId();
@@ -58,6 +103,12 @@ public class Potion {
         entity.sendPacketToViewersAndSelf(eep);
     }
 
+    /**
+     * Sends a packet that a potion effect has been removed from the entity.
+     * <p>
+     * Used internally by {@link net.minestom.server.entity.Player#removeEffect(PotionEffect)}
+     * @param entity
+     */
     public void sendRemovePacket(@NotNull Entity entity) {
         RemoveEntityEffectPacket reep = new RemoveEntityEffectPacket();
         reep.entityId = entity.getEntityId();