/*
 * 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.annotations.Beta;
import java.io.Serializable;

An object which can send data from an object of type T into a PrimitiveSink. Implementations for common types can be found in Funnels.

Note that serialization of bloom filters requires the proper serialization of funnels. When possible, it is recommended that funnels be implemented as a single-element enum to maintain serialization guarantees. See Effective Java (2nd Edition), Item 3: "Enforce the singleton property with a private constructor or an enum type". For example:


public enum PersonFunnel implements Funnel<Person> {
  INSTANCE;
  public void funnel(Person person, PrimitiveSink into) {
    into.putUnencodedChars(person.getFirstName())
        .putUnencodedChars(person.getLastName())
        .putInt(person.getAge());
  }
 }
Author:Dimitris Andreou
Since:11.0
/** * An object which can send data from an object of type {@code T} into a {@code PrimitiveSink}. * Implementations for common types can be found in {@link Funnels}. * * <p>Note that serialization of {@linkplain BloomFilter bloom filters} requires the proper * serialization of funnels. When possible, it is recommended that funnels be implemented as a * single-element enum to maintain serialization guarantees. See Effective Java (2nd Edition), Item * 3: "Enforce the singleton property with a private constructor or an enum type". For example: * * <pre>{@code * public enum PersonFunnel implements Funnel<Person> { * INSTANCE; * public void funnel(Person person, PrimitiveSink into) { * into.putUnencodedChars(person.getFirstName()) * .putUnencodedChars(person.getLastName()) * .putInt(person.getAge()); * } * } * }</pre> * * @author Dimitris Andreou * @since 11.0 */
@Beta public interface Funnel<T> extends Serializable {
Sends a stream of data from the from object into the sink into. There is no requirement that this data be complete enough to fully reconstitute the object later.
Since:12.0 (in Guava 11.0, PrimitiveSink was named Sink)
/** * Sends a stream of data from the {@code from} object into the sink {@code into}. There is no * requirement that this data be complete enough to fully reconstitute the object later. * * @since 12.0 (in Guava 11.0, {@code PrimitiveSink} was named {@code Sink}) */
void funnel(T from, PrimitiveSink into); }