| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.core.composite; |
| |
| import java.io.Serializable; |
| |
| import org.apache.commons.functor.UnaryFunction; |
| import org.apache.commons.functor.UnaryProcedure; |
| import org.apache.commons.functor.adapter.UnaryProcedureUnaryFunction; |
| import org.apache.commons.lang3.Validate; |
| |
| /** |
| * A {@link UnaryProcedure UnaryProcedure} |
| * representing the composition of |
| * {@link UnaryFunction UnaryFunctions}, |
| * "chaining" the output of one to the input |
| * of another. For example, |
| * <pre>new CompositeUnaryProcedure(p).of(f)</pre> |
| * {@link #run runs} to |
| * <code>p.run(f.evaluate(obj))</code>, and |
| * <pre>new CompositeUnaryProcedure(p).of(f).of(g)</pre> |
| * {@link #run runs} |
| * <code>p.run(f.evaluate(g.evaluate(obj)))</code>. |
| * <p> |
| * Note that although this class implements |
| * {@link Serializable}, a given instance will |
| * only be truly <code>Serializable</code> if all the |
| * underlying functors are. Attempts to serialize |
| * an instance whose delegates are not all |
| * <code>Serializable</code> will result in an exception. |
| * </p> |
| * @param <A> the procedure argument type. |
| * @version $Revision$ $Date$ |
| * @author Rodney Waldhoff |
| */ |
| public final class CompositeUnaryProcedure<A> implements UnaryProcedure<A>, Serializable { |
| /** |
| * serialVersionUID declaration. |
| */ |
| private static final long serialVersionUID = -7496282561355676509L; |
| // attributes |
| // ------------------------------------------------------------------------ |
| /** |
| * The adapted composite procedure. |
| */ |
| private final CompositeUnaryFunction<? super A, Object> function; |
| |
| // constructor |
| // ------------------------------------------------------------------------ |
| /** |
| * Create a new CompositeUnaryProcedure. |
| * @param procedure final UnaryProcedure to run |
| */ |
| public CompositeUnaryProcedure(UnaryProcedure<? super A> procedure) { |
| this.function = |
| new CompositeUnaryFunction<A, Object>( |
| new UnaryProcedureUnaryFunction<A, Object>(Validate.notNull( |
| procedure, "procedure must not be null"))); |
| } |
| |
| /** |
| * Create a new CompositeUnaryProcedure. |
| * @param function final CompositeUnaryFunction to run |
| */ |
| private CompositeUnaryProcedure(CompositeUnaryFunction<? super A, Object> function) { |
| this.function = function; |
| } |
| |
| // modifiers |
| // ------------------------------------------------------------------------ |
| /** |
| * Fluently obtain a CompositeUnaryProcedure that runs our procedure against the result of the preceding function. |
| * @param <T> the input function left argument and output procedure argument type |
| * @param preceding UnaryFunction |
| * @return CompositeUnaryProcedure<P> |
| */ |
| public <T> CompositeUnaryProcedure<T> of(UnaryFunction<? super T, ? extends A> preceding) { |
| return new CompositeUnaryProcedure<T>(function.of(preceding)); |
| } |
| |
| // predicate interface |
| // ------------------------------------------------------------------------ |
| /** |
| * {@inheritDoc} |
| */ |
| public void run(A obj) { |
| function.evaluate(obj); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public boolean equals(Object that) { |
| return that == this || (that instanceof CompositeUnaryProcedure<?> |
| && equals((CompositeUnaryProcedure<?>) that)); |
| } |
| |
| /** |
| * Learn whether another CompositeUnaryProcedure is equal to this. |
| * @param that CompositeUnaryProcedure to test |
| * @return boolean |
| */ |
| public boolean equals(CompositeUnaryProcedure<?> that) { |
| return null != that && function.equals(that.function); |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public int hashCode() { |
| int hash = "CompositeUnaryProcedure".hashCode(); |
| hash <<= 2; |
| hash ^= function.hashCode(); |
| return hash; |
| } |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public String toString() { |
| return "CompositeUnaryProcedure<" + function + ">"; |
| } |
| |
| } |