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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) 2011 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 com.google.common.base.Preconditions;
import com.google.errorprone.annotations.Immutable;
import java.io.ByteArrayOutputStream;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.charset.Charset;
import java.util.Arrays;

/**
 * Skeleton implementation of {@link HashFunction}, appropriate for non-streaming algorithms. All
 * the hash computation done using {@linkplain #newHasher()} are delegated to the {@linkplain
 * #hashBytes(byte[], int, int)} method.
 *
 * @author Dimitris Andreou
 */
@Immutable
@ElementTypesAreNonnullByDefault
abstract class AbstractNonStreamingHashFunction extends AbstractHashFunction {
  @Override
  public Hasher newHasher() {
    return newHasher(32);
  }

  @Override
  public Hasher newHasher(int expectedInputSize) {
    Preconditions.checkArgument(expectedInputSize >= 0);
    return new BufferingHasher(expectedInputSize);
  }

  @Override
  public HashCode hashInt(int input) {
    return hashBytes(ByteBuffer.allocate(4).order(ByteOrder.LITTLE_ENDIAN).putInt(input).array());
  }

  @Override
  public HashCode hashLong(long input) {
    return hashBytes(ByteBuffer.allocate(8).order(ByteOrder.LITTLE_ENDIAN).putLong(input).array());
  }

  @Override
  public HashCode hashUnencodedChars(CharSequence input) {
    int len = input.length();
    ByteBuffer buffer = ByteBuffer.allocate(len * 2).order(ByteOrder.LITTLE_ENDIAN);
    for (int i = 0; i < len; i++) {
      buffer.putChar(input.charAt(i));
    }
    return hashBytes(buffer.array());
  }

  @Override
  public HashCode hashString(CharSequence input, Charset charset) {
    return hashBytes(input.toString().getBytes(charset));
  }

  @Override
  public abstract HashCode hashBytes(byte[] input, int off, int len);

  @Override
  public HashCode hashBytes(ByteBuffer input) {
    return newHasher(input.remaining()).putBytes(input).hash();
  }

  /** In-memory stream-based implementation of Hasher. */
  private final class BufferingHasher extends AbstractHasher {
    final ExposedByteArrayOutputStream stream;

    BufferingHasher(int expectedInputSize) {
      this.stream = new ExposedByteArrayOutputStream(expectedInputSize);
    }

    @Override
    public Hasher putByte(byte b) {
      stream.write(b);
      return this;
    }

    @Override
    public Hasher putBytes(byte[] bytes, int off, int len) {
      stream.write(bytes, off, len);
      return this;
    }

    @Override
    public Hasher putBytes(ByteBuffer bytes) {
      stream.write(bytes);
      return this;
    }

    @Override
    public HashCode hash() {
      return hashBytes(stream.byteArray(), 0, stream.length());
    }
  }

  // Just to access the byte[] without introducing an unnecessary copy
  private static final class ExposedByteArrayOutputStream extends ByteArrayOutputStream {
    ExposedByteArrayOutputStream(int expectedInputSize) {
      super(expectedInputSize);
    }

    void write(ByteBuffer input) {
      int remaining = input.remaining();
      if (count + remaining > buf.length) {
        buf = Arrays.copyOf(buf, count + remaining);
      }
      input.get(buf, count, remaining);
      count += remaining;
    }

    byte[] byteArray() {
      return buf;
    }

    int length() {
      return count;
    }
  }
}