[#SPIGOT-5078] Some World.class methods never return.

A few World.class methods never return, and freeze the threads they're being called on.

The methods I couldn't use:

public boolean isChunkGenerated(int x, int z);
public boolean isChunkLoaded(int x, int z);
public Biome getBiome(int x, int z);

This is a snippet of code I used to make sure that those methods are at fault.

package com.dan.NextWorldGenerator;

import org.bukkit.Chunk;
import org.bukkit.World;
import org.bukkit.craftbukkit.libs.org.apache.commons.lang3.Validate;
import org.bukkit.generator.BlockPopulator;

import java.util.Random;

public class ObjectPopulator extends BlockPopulator {

   private TerrainPopulator terrainPopulator;

   public ObjectPopulator(TerrainPopulator terrainPopulator) {

      Validate.notNull(terrainPopulator);

      this.terrainPopulator = terrainPopulator;

   }

   @Override
   public void populate(World world, Random rand, Chunk chunk) {

      System.out.println("Before method attempt...");

      world.isChunkGenerated(chunk.getX() + 5, chunk.getZ() - 5);

      System.out.println("After method attempt.");

//    terrainPopulator.generateObjects(world, chunk.getX(), chunk.getZ());

   }

}

I also have this inside the main class of the plugin:

@Override
public ChunkGenerator getDefaultWorldGenerator(String worldName, String id) {

   Validate.notNull(worldName);

   return new TerrainGenerator(
         futureHandler,
         new ProcessTimer("ChunkGenerator", getLogger()),
         terrainPopulator,
         true);

}

And this inside the TerrainGenerator class:

@Override
public List<BlockPopulator> getDefaultPopulators(World world) {

   Validate.notNull(world);

   List<BlockPopulator> populators = new ArrayList<>(1);
   populators.add(new ObjectPopulator(terrainPopulator));

   return populators;

}

When I remove that method from the class the terrain generates properly.

I included a test plugin to demonstrate the issue. To trigger the bug:

delete the world folder from your server
place the plugin jar inside plugins
add these lines at the end of bukkit.yml:

worlds:
  world:
    generator: WorldsMethodsBugExample

4. start the server
5. log in and move a little bit around the world

[SPIGOT-5078] Some World.class methods never return. Created: 16/Jun/19 Updated: 16/Jun/19 Resolved: 16/Jun/19
Status:	Resolved
Project:	Spigot
Component/s:	None
Affects Version/s:	None
Fix Version/s:	None

[SPIGOT-5078] Some World.class methods never return. Created: 16/Jun/19 Updated: 16/Jun/19 Resolved: 16/Jun/19