Fixed a bug causing server to crash

ElytraServers · Jan 31, 2023 · fa8ac09 · fa8ac09
1 parent f366bef
commit fa8ac09
Show file tree

Hide file tree

Showing 2 changed files with 13 additions and 3 deletions.
diff --git a/src/main/java/cn/elytra/mod/mining/item/MiningHammerBase.java b/src/main/java/cn/elytra/mod/mining/item/MiningHammerBase.java
@@ -75,8 +75,16 @@ public boolean onBlockStartBreak(ItemStack stack, int x, int y, int z, EntityPla
 			// Removed the CoFHCore logic for looping blocks.
 			// Making it more flexible to modify the range of mining blocks.
 
+			BlockPos center = BlockPos.fromMovingObjectPosition(pos);
+			if(center == null) {
+				// fixes NPE
+				// when player destroyed a block and the server lags, the MovingObjectPosition can be null as player moved
+				// its target block to air (unreachable).
+				return false;
+			}
+
 			ImmutableList<BlockPos> breakingBlocks =
-				getMiningBlocks(stack, BlockPos.fromMovingObjectPosition(pos), HitSide.fromSideHit(pos.sideHit), player);
+				getMiningBlocks(stack, center, HitSide.fromSideHit(pos.sideHit), player);
 
 			for(BlockPos bp : breakingBlocks) {
 				x2 = bp.getX();

diff --git a/src/main/java/cn/elytra/mod/mining/util/BlockPos.java b/src/main/java/cn/elytra/mod/mining/util/BlockPos.java
@@ -3,6 +3,7 @@
 import com.google.common.collect.ImmutableList;
 import net.minecraft.util.MovingObjectPosition;
 
+import javax.annotation.Nullable;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -59,8 +60,9 @@ public static BlockPos relativeTo(BlockPos reference, int offsetX, int offsetY,
 		return new BlockPos(reference.x + offsetX, reference.y + offsetY, reference.z + offsetZ);
 	}
 
-	public static BlockPos fromMovingObjectPosition(MovingObjectPosition mop) {
-		return new BlockPos(mop.blockX, mop.blockY, mop.blockZ);
+	@Nullable
+	public static BlockPos fromMovingObjectPosition(@Nullable MovingObjectPosition mop) {
+		return mop == null ? null : new BlockPos(mop.blockX, mop.blockY, mop.blockZ);
 	}
 
 	public static ImmutableList<BlockPos> range(BlockPos p1, BlockPos p2) {