Improved concurrency (should fix #1127 and other C2ME issues)

Author: supermassimo

src/main/java/com/ferreusveritas/dynamictrees/DynamicTrees.java

@@ -18,10 +18,8 @@
 import com.ferreusveritas.dynamictrees.tree.species.Species;
 import com.ferreusveritas.dynamictrees.util.CommonSetup;
 import com.ferreusveritas.dynamictrees.worldgen.DynamicTreeFeature;
-import com.ferreusveritas.dynamictrees.worldgen.structure.VillageTreeReplacement;
 import net.minecraft.data.DataGenerator;
 import net.minecraft.resources.ResourceLocation;
-import net.minecraftforge.client.event.EntityRenderersEvent;
 import net.minecraftforge.data.event.GatherDataEvent;
 import net.minecraftforge.eventbus.api.IEventBus;
 import net.minecraftforge.fml.ModLoadingContext;

src/main/java/com/ferreusveritas/dynamictrees/compat/season/NormalSeasonManager.java

@@ -10,6 +10,7 @@
 
 import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
 import java.util.function.BiPredicate;
 import java.util.function.Function;
 import java.util.function.Supplier;
@@ -18,7 +19,7 @@ public class NormalSeasonManager implements SeasonManager {
 
 	public static final Supplier<SeasonManager> NULL = NormalSeasonManager::new;
 
-    private final Map<ResourceLocation, SeasonContext> seasonContextMap = new HashMap<>();
+    private final Map<ResourceLocation, SeasonContext> seasonContextMap = new ConcurrentHashMap<>();
     private Function<Level, Tuple<SeasonProvider, SeasonGrowthCalculator>> seasonMapper = w -> new Tuple<>(new NullSeasonProvider(), new NullSeasonGrowthCalculator());
 
     public NormalSeasonManager() {

src/main/java/com/ferreusveritas/dynamictrees/systems/poissondisc/LevelPoissonDiscProvider.java

@@ -17,6 +17,7 @@
 import java.util.Map;
 import java.util.Map.Entry;
 import java.util.TreeMap;
+import java.util.concurrent.ConcurrentHashMap;
 
 /**
  * Manages and creates all the Poisson discs in a single level (world).
@@ -26,12 +27,12 @@
 public class LevelPoissonDiscProvider implements PoissonDiscProvider {
 
     private final RadiusCoordinator radiusCoordinator;
-    private final HashMap<ChunkPos, PoissonDiscChunkSet> chunkDiscs;
+    private final Map<ChunkPos, PoissonDiscChunkSet> chunkDiscs;
     private RandomXOR random = new RandomXOR();
     private PoissonDebug debug = PoissonDebug.EMPTY_POISSON_DEBUG;
 
     public LevelPoissonDiscProvider(RadiusCoordinator radCoord) {
-        this.chunkDiscs = new HashMap<>();
+        this.chunkDiscs = new ConcurrentHashMap<>();
         this.radiusCoordinator = radCoord;
     }
 

src/main/java/com/ferreusveritas/dynamictrees/worldgen/BiomeDatabases.java

@@ -7,6 +7,7 @@
 import net.minecraft.resources.ResourceLocation;
 import org.apache.logging.log4j.LogManager;
 
+import java.util.Collections;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
@@ -18,9 +19,9 @@ public final class BiomeDatabases {
 
     private static final BiomeDatabase DEFAULT_DATABASE = new BiomeDatabase();
     /** Dimension names to their respective {@link com.ferreusveritas.dynamictrees.worldgen.BiomeDatabase}. */
-    private static final Map<ResourceLocation, BiomeDatabase> DIMENSIONAL_DATABASES = Maps.newHashMap();
+    private static final Map<ResourceLocation, BiomeDatabase> DIMENSIONAL_DATABASES = Collections.synchronizedMap(Maps.newHashMap());
     /** Dimension names for dimensions that are blacklisted. */
-    private static final Set<ResourceLocation> BLACKLIST = Sets.newHashSet();
+    private static final Set<ResourceLocation> BLACKLIST = Collections.synchronizedSet(Sets.newHashSet());
 
     public static BiomeDatabase getDefault() {
         return DEFAULT_DATABASE;

src/main/java/com/ferreusveritas/dynamictrees/worldgen/DynamicTreeFeature.java

@@ -26,9 +26,7 @@
 import net.minecraft.world.level.levelgen.Heightmap;
 import net.minecraft.world.level.levelgen.feature.Feature;
 import net.minecraft.world.level.levelgen.feature.FeaturePlaceContext;
-import net.minecraft.world.level.levelgen.feature.TreeFeature;
 import net.minecraft.world.level.levelgen.feature.configurations.NoneFeatureConfiguration;
-import net.minecraft.world.level.material.Fluids;
 import net.minecraftforge.registries.ForgeRegistries;
 
 import java.util.Arrays;