MetaContext.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.meta;

import org.apache.doris.common.FeMetaVersion;

/*
 * MetaContext saved the current meta version.
 * And we need to create a thread local meta context for all threads which are about to reading meta.
 */
public class MetaContext {

    private int metaVersion;

    private static ThreadLocal<MetaContext> threadLocalInfo = new ThreadLocal<MetaContext>();

    public MetaContext() {

    }

    public void setMetaVersion(int metaVersion) {
        if (metaVersion < FeMetaVersion.MINIMUM_VERSION_REQUIRED) {
            throw new IllegalArgumentException("Could not set meta version to "
                    + metaVersion + " since it is lower than minimum required version "
                    + FeMetaVersion.MINIMUM_VERSION_REQUIRED);
        }
        this.metaVersion = metaVersion;
    }

    public int getMetaVersion() {
        return metaVersion;
    }

    public void setThreadLocalInfo() {
        threadLocalInfo.set(this);
    }

    public static MetaContext get() {
        return threadLocalInfo.get();
    }

    public static void remove() {
        threadLocalInfo.remove();
    }
}