FileSystemCache.java

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// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package org.apache.doris.fs;

import org.apache.doris.common.CacheFactory;
import org.apache.doris.common.Config;
import org.apache.doris.datasource.property.storage.StorageProperties;
import org.apache.doris.fs.remote.RemoteFileSystem;

import com.github.benmanes.caffeine.cache.LoadingCache;

import java.util.Objects;
import java.util.OptionalLong;

public class FileSystemCache {

    private final LoadingCache<FileSystemCacheKey, RemoteFileSystem> fileSystemCache;

    public FileSystemCache() {
        // no need to set refreshAfterWrite, because the FileSystem is created once and never changed
        CacheFactory fsCacheFactory = new CacheFactory(
                OptionalLong.of(86400L),
                OptionalLong.empty(),
                Config.max_remote_file_system_cache_num,
                false,
                null);
        fileSystemCache = fsCacheFactory.buildCache(this::loadFileSystem);
    }

    private RemoteFileSystem loadFileSystem(FileSystemCacheKey key) {
        return FileSystemFactory.get(key.properties);
    }

    public RemoteFileSystem getRemoteFileSystem(FileSystemCacheKey key) {
        return fileSystemCache.get(key);
    }

    public static class FileSystemCacheKey {
        // eg: hdfs://nameservices1
        private final String fsIdent;
        private final StorageProperties properties;

        public FileSystemCacheKey(String fsIdent, StorageProperties properties) {
            this.fsIdent = fsIdent;
            this.properties = properties;
        }

        @Override
        public boolean equals(Object obj) {
            if (this == obj) {
                return true;
            }
            if (!(obj instanceof FileSystemCacheKey)) {
                return false;
            }
            FileSystemCacheKey o = (FileSystemCacheKey) obj;
            //fixme 需要重写吗
            return fsIdent.equals(o.fsIdent)
                            && properties.equals(o.properties);
        }

        @Override
        public int hashCode() {
            return Objects.hash(properties, fsIdent);
        }
    }
}