Swap some nullable annotations (#10960)

patches/api/Add-more-Witch-API.patch

@@ -48,7 +48,8 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +     *
 +     * @return The potion the witch is drinking
 +     */
-+    @Nullable ItemStack getDrinkingPotion();
++    @org.jetbrains.annotations.NotNull
++    ItemStack getDrinkingPotion();
 +
 +    /**
 +     * Set the potion the Witch should drink

patches/api/Add-villager-reputation-API.patch

@@ -135,7 +135,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +     * @param uniqueId The {@link UUID} of the player to get the reputation of.
 +     * @return The player's copied reputation with this villager.
 +     */
-+    @Nullable
++    @NotNull
 +    public com.destroystokyo.paper.entity.villager.Reputation getReputation(@NotNull UUID uniqueId);
 +
 +    /**

patches/api/EntityShootBowEvent-consumeArrow-and-getArrowItem-AP.patch

@@ -24,7 +24,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +        return this.shouldConsumeItem();
 +    }
 +
-+    @NotNull @Deprecated
++    @Nullable @Deprecated
 +    public ItemStack getArrowItem() {
 +        return this.getConsumable();
 +    }

patches/api/Fix-Spigot-annotation-mistakes.patch

@@ -795,6 +795,19 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
      @Contract("null -> null")
      @Nullable
      public static EntityType fromName(@Nullable String name) {
+diff --git a/src/main/java/org/bukkit/entity/ItemDisplay.java b/src/main/java/org/bukkit/entity/ItemDisplay.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/org/bukkit/entity/ItemDisplay.java
++++ b/src/main/java/org/bukkit/entity/ItemDisplay.java
+@@ -0,0 +0,0 @@ public interface ItemDisplay extends Display {
+      *
+      * @return the displayed item stack
+      */
+-    @Nullable
++    @NotNull // Paper
+     ItemStack getItemStack();
+ 
+     /**
 diff --git a/src/main/java/org/bukkit/entity/LightningStrike.java b/src/main/java/org/bukkit/entity/LightningStrike.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/entity/LightningStrike.java
@@ -885,6 +898,19 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +    @Deprecated // Paper
      public MaterialData getDisplayBlock();
  
+     /**
+diff --git a/src/main/java/org/bukkit/entity/OminousItemSpawner.java b/src/main/java/org/bukkit/entity/OminousItemSpawner.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/org/bukkit/entity/OminousItemSpawner.java
++++ b/src/main/java/org/bukkit/entity/OminousItemSpawner.java
+@@ -0,0 +0,0 @@ public interface OminousItemSpawner extends Entity {
+      *
+      * @return the item
+      */
+-    @Nullable
++    @org.jetbrains.annotations.NotNull // Paper
+     ItemStack getItem();
+ 
      /**
 diff --git a/src/main/java/org/bukkit/entity/Player.java b/src/main/java/org/bukkit/entity/Player.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
@@ -939,6 +965,29 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 -@Deprecated
 +@Deprecated(forRemoval = true) // Paper
  public interface SplashPotion extends ThrownPotion { }
+diff --git a/src/main/java/org/bukkit/entity/ZombieVillager.java b/src/main/java/org/bukkit/entity/ZombieVillager.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/org/bukkit/entity/ZombieVillager.java
++++ b/src/main/java/org/bukkit/entity/ZombieVillager.java
+@@ -0,0 +0,0 @@ public interface ZombieVillager extends Zombie {
+      * Sets the villager profession of this zombie.
+      */
+     @Override
+-    void setVillagerProfession(@Nullable Villager.Profession profession);
++    void setVillagerProfession(@NotNull Villager.Profession profession); // Paper
+ 
+     /**
+      * Returns the villager profession of this zombie.
+      *
+-     * @return the profession or null
++     * @return the profession
+      */
+     @Override
+-    @Nullable
++    @NotNull // Paper
+     Villager.Profession getVillagerProfession();
+ 
+     /**
 diff --git a/src/main/java/org/bukkit/entity/memory/MemoryKey.java b/src/main/java/org/bukkit/entity/memory/MemoryKey.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/entity/memory/MemoryKey.java

patches/server/Missing-Entity-API.patch

@@ -1020,21 +1020,13 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +    @Override
 +    public org.bukkit.Location getAnchorLocation() {
 +        net.minecraft.core.BlockPos pos = this.getHandle().anchorPoint;
-+        if (pos == null) {
-+            return null;
-+        }
-+
 +        return io.papermc.paper.util.MCUtil.toLocation(this.getHandle().level(), pos);
 +    }
 +
 +    @Override
 +    public void setAnchorLocation(org.bukkit.Location location) {
-+        net.minecraft.core.BlockPos pos = null;
-+        if (location != null) {
-+            pos = io.papermc.paper.util.MCUtil.toBlockPosition(location);
-+        }
-+
-+        this.getHandle().anchorPoint = pos;
++        com.google.common.base.Preconditions.checkArgument(location != null, "location cannot be null");
++        this.getHandle().anchorPoint = io.papermc.paper.util.MCUtil.toBlockPosition(location);
 +    }
      // Paper end
  }

patches/server/More-Projectile-API.patch

@@ -589,29 +589,28 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
          super(server, entity);
      }
  
--    @Override
++    // Paper - moved to AbstractProjectile
++
++    @Override
++    public org.bukkit.entity.Entity getTarget() {
++        return this.getHandle().getTarget() != null ? this.getHandle().getTarget().getBukkitEntity() : null;
++    }
++
+     @Override
 -    public ProjectileSource getShooter() {
 -        return this.getHandle().projectileSource;
--    }
--
--    @Override
++    public void setTarget(org.bukkit.entity.Entity target) {
++        Preconditions.checkState(!this.getHandle().generation, "Cannot set target during world generation");
++
++        this.getHandle().setTarget(target == null ? null : ((CraftEntity) target).getHandle());
+     }
+ 
+     @Override
 -    public void setShooter(ProjectileSource shooter) {
 -        if (shooter instanceof Entity) {
 -            this.getHandle().setOwner(((CraftEntity) shooter).getHandle());
 -        } else {
 -            this.getHandle().setOwner(null);
--        }
--        this.getHandle().projectileSource = shooter;
--    }
-+    // Paper - moved to AbstractProjectile
- 
-     @Override
-     public org.bukkit.entity.Entity getTarget() {
-@@ -0,0 +0,0 @@ public class CraftShulkerBullet extends AbstractProjectile implements ShulkerBul
-         this.getHandle().setTarget(target == null ? null : ((CraftEntity) target).getHandle());
-     }
- 
-+    @Override
 +    public org.bukkit.util.Vector getTargetDelta() {
 +        net.minecraft.world.entity.projectile.ShulkerBullet bullet = this.getHandle();
 +        return new org.bukkit.util.Vector(bullet.targetDeltaX, bullet.targetDeltaY, bullet.targetDeltaZ);
@@ -627,27 +626,35 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +
 +    @Override
 +    public org.bukkit.block.BlockFace getCurrentMovementDirection() {
-+        return org.bukkit.craftbukkit.block.CraftBlock.notchToBlockFace(this.getHandle().currentMoveDirection);
-+    }
-+
-+    @Override
++        net.minecraft.core.Direction dir = this.getHandle().currentMoveDirection;
++        if (dir == null) {
++            return null; // random dir
+         }
+-        this.getHandle().projectileSource = shooter;
++        return org.bukkit.craftbukkit.block.CraftBlock.notchToBlockFace(dir);
+     }
+ 
+     @Override
+-    public org.bukkit.entity.Entity getTarget() {
+-        return this.getHandle().getTarget() != null ? this.getHandle().getTarget().getBukkitEntity() : null;
 +    public void setCurrentMovementDirection(org.bukkit.block.BlockFace movementDirection) {
 +        this.getHandle().currentMoveDirection = org.bukkit.craftbukkit.block.CraftBlock.blockFaceToNotch(movementDirection);
-+    }
-+
-+    @Override
+     }
+ 
+     @Override
+-    public void setTarget(org.bukkit.entity.Entity target) {
+-        Preconditions.checkState(!this.getHandle().generation, "Cannot set target during world generation");
 +    public int getFlightSteps() {
 +        return this.getHandle().flightSteps;
 +    }
-+
+ 
+-        this.getHandle().setTarget(target == null ? null : ((CraftEntity) target).getHandle());
 +    @Override
 +    public void setFlightSteps(int steps) {
 +        this.getHandle().flightSteps = steps;
-+    }
-+
+     }
+ 
      @Override
-     public String toString() {
-         return "CraftShulkerBullet";
 diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftThrownPotion.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftThrownPotion.java
 index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
 --- a/src/main/java/org/bukkit/craftbukkit/entity/CraftThrownPotion.java