UnpooledDirectByteBuf Class — netty Architecture

Source Code

buffer/src/main/java/io/netty/buffer/UnpooledDirectByteBuf.java lines 39–777

public class UnpooledDirectByteBuf extends AbstractReferenceCountedByteBuf {

    private final ByteBufAllocator alloc;

    CleanableDirectBuffer cleanable;
    ByteBuffer buffer; // accessed by UnpooledUnsafeNoCleanerDirectByteBuf.reallocateDirect()
    private ByteBuffer tmpNioBuf;
    private int capacity;
    private boolean doNotFree;

    /**
     * Creates a new direct buffer.
     *
     * @param initialCapacity the initial capacity of the underlying direct buffer
     * @param maxCapacity     the maximum capacity of the underlying direct buffer
     */
    public UnpooledDirectByteBuf(ByteBufAllocator alloc, int initialCapacity, int maxCapacity) {
        super(maxCapacity);
        ObjectUtil.checkNotNull(alloc, "alloc");
        checkPositiveOrZero(initialCapacity, "initialCapacity");
        checkPositiveOrZero(maxCapacity, "maxCapacity");
        if (initialCapacity > maxCapacity) {
            throw new IllegalArgumentException(String.format(
                    "initialCapacity(%d) > maxCapacity(%d)", initialCapacity, maxCapacity));
        }

        this.alloc = alloc;
        setByteBuffer(allocateDirectBuffer(initialCapacity), false);
    }

    /**
     * Creates a new direct buffer by wrapping the specified initial buffer.
     *
     * @param maxCapacity the maximum capacity of the underlying direct buffer
     */
    protected UnpooledDirectByteBuf(ByteBufAllocator alloc, ByteBuffer initialBuffer, int maxCapacity) {
        this(alloc, initialBuffer, maxCapacity, false, true);
    }

    UnpooledDirectByteBuf(ByteBufAllocator alloc, ByteBuffer initialBuffer,
            int maxCapacity, boolean doFree, boolean slice) {
        super(maxCapacity);
        ObjectUtil.checkNotNull(alloc, "alloc");
        ObjectUtil.checkNotNull(initialBuffer, "initialBuffer");
        if (!initialBuffer.isDirect()) {
            throw new IllegalArgumentException("initialBuffer is not a direct buffer.");
        }
        if (initialBuffer.isReadOnly()) {
            throw new IllegalArgumentException("initialBuffer is a read-only buffer.");
        }

        int initialCapacity = initialBuffer.remaining();
        if (initialCapacity > maxCapacity) {
            throw new IllegalArgumentException(String.format(
                    "initialCapacity(%d) > maxCapacity(%d)", initialCapacity, maxCapacity));
        }

        this.alloc = alloc;
        doNotFree = !doFree;
        setByteBuffer((slice ? initialBuffer.slice() : initialBuffer).order(ByteOrder.BIG_ENDIAN), false);
        writerIndex(initialCapacity);
    }

    /**
     * Allocate a new direct {@link ByteBuffer} with the given initialCapacity.
     * @deprecated Use {@link #allocateDirectBuffer(int)} instead.
     */
    @Deprecated
    protected ByteBuffer allocateDirect(int initialCapacity) {
        return ByteBuffer.allocateDirect(initialCapacity);
    }

    /**
     * Free a direct {@link ByteBuffer}
     * @deprecated Use {@link #allocateDirectBuffer(int)} instead.
     */
    @Deprecated
    protected void freeDirect(ByteBuffer buffer) {
        PlatformDependent.freeDirectBuffer(buffer);
    }