import org.apache.cassandra.db.index.SecondaryIndexBuilder; //导入依赖的package包/类
/**
 * Is not scheduled, because it is performing disjoint work from sstable compaction.
 */
public Future<?> submitIndexBuild(final SecondaryIndexBuilder builder)
{
    Runnable runnable = new Runnable()
    {
        public void run()
        {
            metrics.beginCompaction(builder);
            try
            {
                builder.build();
            }
            finally
            {
                metrics.finishCompaction(builder);
            }
        }
    };
    if (executor.isShutdown())
    {
        logger.info("Compaction executor has shut down, not submitting index build");
        return null;
    }

    return executor.submit(runnable);
}
 

import org.apache.cassandra.db.index.SecondaryIndexBuilder; //导入依赖的package包/类
/**
 * Is not scheduled, because it is performing disjoint work from sstable compaction.
 */
public Future<?> submitIndexBuild(final SecondaryIndexBuilder builder)
{
    Runnable runnable = new Runnable()
    {
        public void run()
        {
            metrics.beginCompaction(builder);
            try
            {
                builder.build();
            }
            finally
            {
                metrics.finishCompaction(builder);
            }
        }
    };

    return executor.submit(runnable);
}
 

import org.apache.cassandra.db.index.SecondaryIndexBuilder; //导入依赖的package包/类
/**
 * Is not scheduled, because it is performing disjoint work from sstable compaction.
 */
public Future<?> submitIndexBuild(final SecondaryIndexBuilder builder)
{
    Runnable runnable = new Runnable()
    {
        public void run()
        {
            compactionLock.readLock().lock();
            try
            {
                metrics.beginCompaction(builder);
                try
                {
                    builder.build();
                }
                finally
                {
                    metrics.finishCompaction(builder);
                }
            }
            finally
            {
                compactionLock.readLock().unlock();
            }
        }
    };

    // don't submit to the executor if the compaction lock is held by the current thread. Instead return a simple
    // future that will be immediately immediately get()ed and executed. Happens during a migration, which locks
    // the compaction thread and then reinitializes a ColumnFamilyStore. Under normal circumstances, CFS spawns
    // index jobs to the compaction manager (this) and blocks on them.
    if (compactionLock.isWriteLockedByCurrentThread())
        return new SimpleFuture(runnable);
    else
        return executor.submit(runnable);
}