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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging 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 static com.google.common.base.Preconditions.checkNotNull;

import java.nio.charset.Charset;

/**
 * An abstract composition of multiple hash functions. {@linkplain #newHasher()} delegates to the
 * {@code Hasher} objects of the delegate hash functions, and in the end, they are used by
 * {@linkplain #makeHash(Hasher[])} that constructs the final {@code HashCode}.
 *
 * @author Dimitris Andreou
 */
abstract class AbstractCompositeHashFunction extends AbstractStreamingHashFunction {
  final HashFunction[] functions;

  AbstractCompositeHashFunction(HashFunction... functions) {
    for (HashFunction function : functions) {
      checkNotNull(function);
    }
    this.functions = functions;
  }

  /**
   * Constructs a {@code HashCode} from the {@code Hasher} objects of the functions. Each of them
   * has consumed the entire input and they are ready to output a {@code HashCode}. The order of
   * the hashers are the same order as the functions given to the constructor.
   */
  // this could be cleaner if it passed HashCode[], but that would create yet another array...
  /* protected */ abstract HashCode makeHash(Hasher[] hashers);

  @Override
  public Hasher newHasher() {
    final Hasher[] hashers = new Hasher[functions.length];
    for (int i = 0; i < hashers.length; i++) {
      hashers[i] = functions[i].newHasher();
    }
    return new Hasher() {
      @Override public Hasher putByte(byte b) {
        for (Hasher hasher : hashers) {
          hasher.putByte(b);
        }
        return this;
      }

      @Override public Hasher putBytes(byte[] bytes) {
        for (Hasher hasher : hashers) {
          hasher.putBytes(bytes);
        }
        return this;
      }

      @Override public Hasher putBytes(byte[] bytes, int off, int len) {
        for (Hasher hasher : hashers) {
          hasher.putBytes(bytes, off, len);
        }
        return this;
      }

      @Override public Hasher putShort(short s) {
        for (Hasher hasher : hashers) {
          hasher.putShort(s);
        }
        return this;
      }

      @Override public Hasher putInt(int i) {
        for (Hasher hasher : hashers) {
          hasher.putInt(i);
        }
        return this;
      }

      @Override public Hasher putLong(long l) {
        for (Hasher hasher : hashers) {
          hasher.putLong(l);
        }
        return this;
      }

      @Override public Hasher putFloat(float f) {
        for (Hasher hasher : hashers) {
          hasher.putFloat(f);
        }
        return this;
      }

      @Override public Hasher putDouble(double d) {
        for (Hasher hasher : hashers) {
          hasher.putDouble(d);
        }
        return this;
      }

      @Override public Hasher putBoolean(boolean b) {
        for (Hasher hasher : hashers) {
          hasher.putBoolean(b);
        }
        return this;
      }

      @Override public Hasher putChar(char c) {
        for (Hasher hasher : hashers) {
          hasher.putChar(c);
        }
        return this;
      }

      @Override public Hasher putUnencodedChars(CharSequence chars) {
        for (Hasher hasher : hashers) {
          hasher.putUnencodedChars(chars);
        }
        return this;
      }

      @Override public Hasher putString(CharSequence chars, Charset charset) {
        for (Hasher hasher : hashers) {
          hasher.putString(chars, charset);
        }
        return this;
      }

      @Override public  Hasher putObject(T instance, Funnel funnel) {
        for (Hasher hasher : hashers) {
          hasher.putObject(instance, funnel);
        }
        return this;
      }

      @Override public HashCode hash() {
        return makeHash(hashers);
      }
    };
  }

  private static final long serialVersionUID = 0L;
}