Class AbstractPool

core/src/main/java/io/questdb/cairo/pool/AbstractPool.java:36–106

import java.io.Closeable;

public abstract class AbstractPool implements Closeable {
    public static final long CLOSED = Unsafe.getFieldOffset(AbstractPool.class, "closed");
    public static final long UNALLOCATED = -1L;
    private static final int FALSE = 0;
    private static final int TRUE = 1;
    protected final MicrosecondClock clock;
    protected final FilesFacade ff;
    private final CairoConfiguration configuration;
    private final long inactiveTtlUs;
    @SuppressWarnings({"FieldCanBeLocal", "FieldMayBeFinal"})
    private volatile int closed = FALSE;
    // keep volatile to avoid races around listener clean up in tests
    private volatile PoolListener eventListener;

    public AbstractPool(CairoConfiguration configuration, long inactiveTtlMillis) {
        this.configuration = configuration;
        this.ff = configuration.getFilesFacade();
        this.clock = configuration.getMicrosecondClock();
        this.inactiveTtlUs = inactiveTtlMillis * 1000;
    }

    @Override
    public void close() {
        if (Unsafe.cas(this, CLOSED, FALSE, TRUE)) {
            closePool();
        }
    }

    public CairoConfiguration getConfiguration() {
        return configuration;
    }

    public PoolListener getPoolListener() {
        return eventListener;
    }

    public boolean releaseAll() {
        return releaseAll(Long.MAX_VALUE);
    }

    public boolean releaseInactive() {
        return releaseAll(clock.getTicks() - inactiveTtlUs);
    }

    @TestOnly
    public boolean reopen() {
        return Unsafe.cas(this, CLOSED, TRUE, FALSE);
    }

    public void setPoolListener(PoolListener eventListener) {
        this.eventListener = eventListener;
    }

    protected void closePool() {
        releaseAll(Long.MAX_VALUE);
        notifyListener(Thread.currentThread().threadId(), null, PoolListener.EV_POOL_CLOSED);
    }