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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * Copyright 2015 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.channel.epoll;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufAllocator;
import io.netty.channel.RecvByteBufAllocator.DelegatingHandle;
import io.netty.channel.RecvByteBufAllocator.ExtendedHandle;
import io.netty.channel.unix.PreferredDirectByteBufAllocator;
import io.netty.util.UncheckedBooleanSupplier;

class EpollRecvByteAllocatorHandle extends DelegatingHandle implements ExtendedHandle {
    private final PreferredDirectByteBufAllocator preferredDirectByteBufAllocator =
            new PreferredDirectByteBufAllocator();
    private final UncheckedBooleanSupplier defaultMaybeMoreDataSupplier = new UncheckedBooleanSupplier() {
        @Override
        public boolean get() {
            return maybeMoreDataToRead();
        }
    };
    private boolean isEdgeTriggered;
    private boolean receivedRdHup;

    EpollRecvByteAllocatorHandle(ExtendedHandle handle) {
        super(handle);
    }

    final void receivedRdHup() {
        receivedRdHup = true;
    }

    final boolean isReceivedRdHup() {
        return receivedRdHup;
    }

    boolean maybeMoreDataToRead() {
        /**
         * EPOLL ET requires that we read until we get an EAGAIN
         * (see Q9 in epoll man). However in order to
         * respect auto read we supporting reading to stop if auto read is off. It is expected that the
         * {@link #EpollSocketChannel} implementations will track if we are in edgeTriggered mode and all data was not
         * read, and will force a EPOLLIN ready event.
         *
         * It is assumed RDHUP is handled externally by checking {@link #isReceivedRdHup()}.
         */
        return (isEdgeTriggered && lastBytesRead() > 0) ||
               (!isEdgeTriggered && lastBytesRead() == attemptedBytesRead());
    }

    final void edgeTriggered(boolean edgeTriggered) {
        isEdgeTriggered = edgeTriggered;
    }

    final boolean isEdgeTriggered() {
        return isEdgeTriggered;
    }

    @Override
    public final ByteBuf allocate(ByteBufAllocator alloc) {
        // We need to ensure we always allocate a direct ByteBuf as we can only use a direct buffer to read via JNI.
        preferredDirectByteBufAllocator.updateAllocator(alloc);
        return delegate().allocate(preferredDirectByteBufAllocator);
    }

    @Override
    public final boolean continueReading(UncheckedBooleanSupplier maybeMoreDataSupplier) {
        return ((ExtendedHandle) delegate()).continueReading(maybeMoreDataSupplier);
    }

    @Override
    public final boolean continueReading() {
        // We must override the supplier which determines if there maybe more data to read.
        return continueReading(defaultMaybeMoreDataSupplier);
    }
}