com.google.common.base.Predicate Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of swagger-all Show documentation
swagger-all is a rebundled verison of Swagger as one OSGi bundle.
The newest version!
/*
 * Copyright (C) 2007 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.base;

import com.google.common.annotations.GwtCompatible;

import javax.annotation.Nullable;

/**
 * Determines a true or false value for a given input.
 *
 * The {@link Predicates} class provides common predicates and related utilities.
 *
 * 
See the Guava User Guide article on the use of {@code
 * Predicate}.
 *
 * @author Kevin Bourrillion
 * @since 2.0 (imported from Google Collections Library)
 */
@GwtCompatible
public interface Predicate {
  /**
   * Returns the result of applying this predicate to {@code input}. This method is generally
   * expected, but not absolutely required, to have the following properties:
   *
   * 

   * Its execution does not cause any observable side effects.
   * 
The computation is consistent with equals; that is, {@link Objects#equal
   *     Objects.equal}{@code (a, b)} implies that {@code predicate.apply(a) ==
   *     predicate.apply(b))}.
   * 
   *
   * @throws NullPointerException if {@code input} is null and this predicate does not accept null
   *     arguments
   */
  boolean apply(@Nullable T input);

  /**
   * Indicates whether another object is equal to this predicate.
   *
   * Most implementations will have no reason to override the behavior of {@link Object#equals}.
   * However, an implementation may also choose to return {@code true} whenever {@code object} is a
   * {@link Predicate} that it considers interchangeable with this one. "Interchangeable"
   * typically means that {@code this.apply(t) == that.apply(t)} for all {@code t} of type
   * {@code T}). Note that a {@code false} result from this method does not imply that the
   * predicates are known not to be interchangeable.
   */
  @Override
  boolean equals(@Nullable Object object);
}