| /* |
| * Copyright 2003,2004 The Apache Software Foundation. |
| * |
| * 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 org.apache.commons.functor; |
| |
| /** |
| * A functor that takes one argument and returns a <code>boolean</code> value. |
| * <p> |
| * Implementors are encouraged but not required to make their functors |
| * {@link java.io.Serializable Serializable}. |
| * </p> |
| * |
| * @since 1.0 |
| * @version $Revision$ $Date$ |
| * @author Rodney Waldhoff |
| */ |
| public interface UnaryPredicate { |
| /** |
| * Evaluate this predicate. |
| * |
| * @param obj the object to test |
| * @return the result of this test |
| */ |
| boolean test(Object obj); |
| |
| /** |
| * Returns a human readable description of this functor. |
| * Implementators are strongly encouraged but not |
| * strictly required to override the default {@link Object} |
| * implementation of this method. |
| * |
| * @return a human readable description of this functor |
| */ |
| String toString(); |
| |
| /** |
| * Returns a hash code for this functor adhering to the |
| * general {@link Object#hashCode Object.hashCode} contract. |
| * Implementators are strongly encouraged but not |
| * strictly required to override the default {@link Object} |
| * implementation of this method. |
| * |
| * @see #equals |
| * @return a hash code for this functor |
| */ |
| int hashCode(); |
| |
| /** |
| * Indicates whether some other object is "equal to" |
| * this functor. This method must adhere to |
| * general {@link Object#equals Object.equals} contract. |
| * Additionally, this method can return |
| * <tt>true</tt> <i>only</i> if the specified Object implements |
| * the same functor interface and is known to produce the same |
| * results and/or side-effects for the same arguments (if any). |
| * <p> |
| * While implementators are strongly encouraged to override |
| * the default Object implementation of this method, |
| * note that the default Object implementation |
| * does in fact adhere to the functor <code>equals</code> contract. |
| * </p> |
| * @param that the object to compare this functor to |
| * @see #hashCode |
| * @return <code>true</code> iff the given object implements |
| * this functor interface, and is known to produce the same |
| * results and/or side-effects for the same arguments |
| * (if any). |
| */ |
| boolean equals(Object that); |
| } |