UnpooledByteBufAllocator Class — netty Architecture

Source Code

buffer/src/main/java/io/netty/buffer/UnpooledByteBufAllocator.java lines 28–304

public final class UnpooledByteBufAllocator extends AbstractByteBufAllocator implements ByteBufAllocatorMetricProvider {

    private final UnpooledByteBufAllocatorMetric metric = new UnpooledByteBufAllocatorMetric();
    private final boolean disableLeakDetector;
    private final boolean noCleaner;

    /**
     * Default instance which uses leak-detection for direct buffers.
     */
    public static final UnpooledByteBufAllocator DEFAULT =
            new UnpooledByteBufAllocator(PlatformDependent.directBufferPreferred());

    /**
     * Create a new instance which uses leak-detection for direct buffers.
     *
     * @param preferDirect {@code true} if {@link #buffer(int)} should try to allocate a direct buffer rather than
     *                     a heap buffer
     */
    public UnpooledByteBufAllocator(boolean preferDirect) {
        this(preferDirect, false);
    }

    /**
     * Create a new instance
     *
     * @param preferDirect {@code true} if {@link #buffer(int)} should try to allocate a direct buffer rather than
     *                     a heap buffer
     * @param disableLeakDetector {@code true} if the leak-detection should be disabled completely for this
     *                            allocator. This can be useful if the user just want to depend on the GC to handle
     *                            direct buffers when not explicit released.
     */
    public UnpooledByteBufAllocator(boolean preferDirect, boolean disableLeakDetector) {
        this(preferDirect, disableLeakDetector, PlatformDependent.useDirectBufferNoCleaner());
    }

    /**
     * Create a new instance
     *
     * @param preferDirect {@code true} if {@link #buffer(int)} should try to allocate a direct buffer rather than
     *                     a heap buffer
     * @param disableLeakDetector {@code true} if the leak-detection should be disabled completely for this
     *                            allocator. This can be useful if the user just want to depend on the GC to handle
     *                            direct buffers when not explicit released.
     * @param tryNoCleaner {@code true} if we should try to use {@link PlatformDependent#allocateDirectNoCleaner(int)}
     *                            to allocate direct memory.
     */
    public UnpooledByteBufAllocator(boolean preferDirect, boolean disableLeakDetector, boolean tryNoCleaner) {
        super(preferDirect);
        this.disableLeakDetector = disableLeakDetector;
        noCleaner = tryNoCleaner && PlatformDependent.hasUnsafe()
                && PlatformDependent.hasDirectBufferNoCleanerConstructor();
    }

    @Override
    protected ByteBuf newHeapBuffer(int initialCapacity, int maxCapacity) {
        return PlatformDependent.hasUnsafe() ?
                new InstrumentedUnpooledUnsafeHeapByteBuf(this, initialCapacity, maxCapacity) :
                new InstrumentedUnpooledHeapByteBuf(this, initialCapacity, maxCapacity);
    }

    @Override
    protected ByteBuf newDirectBuffer(int initialCapacity, int maxCapacity) {
        final ByteBuf buf;
        if (PlatformDependent.hasUnsafe()) {
            buf = noCleaner ? new InstrumentedUnpooledUnsafeNoCleanerDirectByteBuf(this, initialCapacity, maxCapacity) :
                    new InstrumentedUnpooledUnsafeDirectByteBuf(this, initialCapacity, maxCapacity);
        } else {
            buf = new InstrumentedUnpooledDirectByteBuf(this, initialCapacity, maxCapacity);
        }
        return disableLeakDetector ? buf : toLeakAwareBuffer(buf);
    }

    @Override
    public CompositeByteBuf compositeHeapBuffer(int maxNumComponents) {
        CompositeByteBuf buf = new CompositeByteBuf(this, false, maxNumComponents);
        return disableLeakDetector ? buf : toLeakAwareBuffer(buf);
    }

    @Override
    public CompositeByteBuf compositeDirectBuffer(int maxNumComponents) {
        CompositeByteBuf buf = new CompositeByteBuf(this, true, maxNumComponents);