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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 (C) 2012 The Guava Authors
 *
 * Licensed 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
 *
 * http://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 com.google.common.hash;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkPositionIndexes;

import com.google.common.primitives.Chars;
import com.google.common.primitives.Ints;
import com.google.common.primitives.Longs;
import com.google.common.primitives.Shorts;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;

/**
 * Abstract {@link Hasher} that handles converting primitives to bytes using a scratch {@code
 * ByteBuffer} and streams all bytes to a sink to compute the hash.
 *
 * @author Colin Decker
 */
@ElementTypesAreNonnullByDefault
abstract class AbstractByteHasher extends AbstractHasher {
  private final ByteBuffer scratch = ByteBuffer.allocate(8).order(ByteOrder.LITTLE_ENDIAN);

  /** Updates this hasher with the given byte. */
  protected abstract void update(byte b);

  /** Updates this hasher with the given bytes. */
  protected void update(byte[] b) {
    update(b, 0, b.length);
  }

  /** Updates this hasher with {@code len} bytes starting at {@code off} in the given buffer. */
  protected void update(byte[] b, int off, int len) {
    for (int i = off; i < off + len; i++) {
      update(b[i]);
    }
  }

  /** Updates this hasher with bytes from the given buffer. */
  protected void update(ByteBuffer b) {
    if (b.hasArray()) {
      update(b.array(), b.arrayOffset() + b.position(), b.remaining());
      Java8Compatibility.position(b, b.limit());
    } else {
      for (int remaining = b.remaining(); remaining > 0; remaining--) {
        update(b.get());
      }
    }
  }

  /** Updates the sink with the given number of bytes from the buffer. */
  @CanIgnoreReturnValue
  private Hasher update(int bytes) {
    try {
      update(scratch.array(), 0, bytes);
    } finally {
      Java8Compatibility.clear(scratch);
    }
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putByte(byte b) {
    update(b);
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putBytes(byte[] bytes) {
    checkNotNull(bytes);
    update(bytes);
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putBytes(byte[] bytes, int off, int len) {
    checkPositionIndexes(off, off + len, bytes.length);
    update(bytes, off, len);
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putBytes(ByteBuffer bytes) {
    update(bytes);
    return this;
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putShort(short s) {
    scratch.putShort(s);
    return update(Shorts.BYTES);
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putInt(int i) {
    scratch.putInt(i);
    return update(Ints.BYTES);
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putLong(long l) {
    scratch.putLong(l);
    return update(Longs.BYTES);
  }

  @Override
  @CanIgnoreReturnValue
  public Hasher putChar(char c) {
    scratch.putChar(c);
    return update(Chars.BYTES);
  }
}