Code/net/minecraft/world/level/chunk/storage/RegionFileVersion.java

package net.minecraft.world.level.chunk.storage;

import com.mojang.logging.LogUtils;
import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
import it.unimi.dsi.fastutil.objects.Object2ObjectMap;
import it.unimi.dsi.fastutil.objects.Object2ObjectOpenHashMap;
import java.io.BufferedOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.DeflaterOutputStream;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import java.util.zip.InflaterInputStream;
import javax.annotation.Nullable;
import net.jpountz.lz4.LZ4BlockInputStream;
import net.jpountz.lz4.LZ4BlockOutputStream;
import net.minecraft.util.FastBufferedInputStream;
import org.slf4j.Logger;

public class RegionFileVersion {
    private static final Logger LOGGER = LogUtils.getLogger();
    private static final Int2ObjectMap<RegionFileVersion> VERSIONS = new Int2ObjectOpenHashMap<>();
    private static final Object2ObjectMap<String, RegionFileVersion> VERSIONS_BY_NAME = new Object2ObjectOpenHashMap<>();
    public static final RegionFileVersion VERSION_GZIP = register(
        new RegionFileVersion(
            1,
            null,
            p_63767_ -> new FastBufferedInputStream(new GZIPInputStream(p_63767_)),
            p_63769_ -> new BufferedOutputStream(new GZIPOutputStream(p_63769_))
        )
    );
    public static final RegionFileVersion VERSION_DEFLATE = register(
        new RegionFileVersion(
            2,
            "deflate",
            p_196964_ -> new FastBufferedInputStream(new InflaterInputStream(p_196964_)),
            p_196966_ -> new BufferedOutputStream(new DeflaterOutputStream(p_196966_))
        )
    );
    public static final RegionFileVersion VERSION_NONE = register(new RegionFileVersion(3, "none", FastBufferedInputStream::new, BufferedOutputStream::new));
    public static final RegionFileVersion VERSION_LZ4 = register(
        new RegionFileVersion(
            4,
            "lz4",
            p_327422_ -> new FastBufferedInputStream(new LZ4BlockInputStream(p_327422_)),
            p_327421_ -> new BufferedOutputStream(new LZ4BlockOutputStream(p_327421_))
        )
    );
    public static final RegionFileVersion VERSION_CUSTOM = register(new RegionFileVersion(127, null, p_327423_ -> {
        throw new UnsupportedOperationException();
    }, p_327424_ -> {
        throw new UnsupportedOperationException();
    }));
    public static final RegionFileVersion DEFAULT = VERSION_DEFLATE;
    private static volatile RegionFileVersion selected = DEFAULT;
    private final int id;
    @Nullable
    private final String optionName;
    private final RegionFileVersion.StreamWrapper<InputStream> inputWrapper;
    private final RegionFileVersion.StreamWrapper<OutputStream> outputWrapper;

    private RegionFileVersion(
        int p_63752_, @Nullable String p_336103_, RegionFileVersion.StreamWrapper<InputStream> p_63753_, RegionFileVersion.StreamWrapper<OutputStream> p_63754_
    ) {
        this.id = p_63752_;
        this.optionName = p_336103_;
        this.inputWrapper = p_63753_;
        this.outputWrapper = p_63754_;
    }

    private static RegionFileVersion register(RegionFileVersion p_63759_) {
        VERSIONS.put(p_63759_.id, p_63759_);
        if (p_63759_.optionName != null) {
            VERSIONS_BY_NAME.put(p_63759_.optionName, p_63759_);
        }

        return p_63759_;
    }

    @Nullable
    public static RegionFileVersion fromId(int p_63757_) {
        return VERSIONS.get(p_63757_);
    }

    public static void configure(String p_335730_) {
        RegionFileVersion regionfileversion = VERSIONS_BY_NAME.get(p_335730_);
        if (regionfileversion != null) {
            selected = regionfileversion;
        } else {
            LOGGER.error(
                "Invalid `region-file-compression` value `{}` in server.properties. Please use one of: {}", p_335730_, String.join(", ", VERSIONS_BY_NAME.keySet())
            );
        }
    }

    public static RegionFileVersion getSelected() {
        return selected;
    }

    public static boolean isValidVersion(int p_63765_) {
        return VERSIONS.containsKey(p_63765_);
    }

    public int getId() {
        return this.id;
    }

    public OutputStream wrap(OutputStream p_63763_) throws IOException {
        return this.outputWrapper.wrap(p_63763_);
    }

    public InputStream wrap(InputStream p_63761_) throws IOException {
        return this.inputWrapper.wrap(p_63761_);
    }

    @FunctionalInterface
    interface StreamWrapper<O> {
        O wrap(O p_63771_) throws IOException;
    }
}