SyncTask.java

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package org.apache.doris.task;

import org.apache.doris.load.sync.SyncChannelCallback;
import org.apache.doris.task.SerialExecutorService.SerialRunnable;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

/**
 * SyncTask is a runnable to submit to SerialExecutorService. Each
 * SyncTask will have an index to submit to the corresponding slot
 * in the SerialExecutorService. And SerialExecutorService ensures
 * that all SyncTasks submitted with the same index are always
 * executed in the order of submission.
 */
public abstract class SyncTask implements SerialRunnable {
    private static final Logger LOG = LogManager.getLogger(SyncTask.class);

    protected long signature;
    /**
     * Each index corresponds to a slot in the SerialExecutorService.
     * It should only be assigned by the getNextIndex() method in the
     * SyncTaskPool. SyncTasks with the same index are always executed
     * in the order of submission.
     */
    protected int index;
    protected SyncChannelCallback callback;

    public SyncTask(long signature, int index, SyncChannelCallback callback) {
        this.signature = signature;
        this.index = index;
        this.callback = callback;
    }

    @Override
    public void run() {
        try {
            exec();
        } catch (Exception e) {
            String errMsg = "channel " + signature + ", " + "msg: " + e.getMessage();
            LOG.error("sync task exec error: {}", errMsg);
            callback.onFailed(errMsg);
        }
    }

    public int getIndex() {
        return this.index;
    }

    /**
     * implement in child
     */
    protected abstract void exec() throws Exception;
}