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feilong is a suite of core and expanded libraries that include utility classes, http, excel,cvs, io classes, and much much more.
/*
* 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 com.feilong.lib.collection4.functors;
import java.io.Serializable;
import org.apache.commons.collections4.Predicate;
import org.apache.commons.collections4.Transformer;
import com.feilong.lib.collection4.FunctorException;
/**
* Predicate implementation that returns the result of a transformer.
*
* @param
*
* @since 3.0
*/
public final class TransformerPredicate implements Predicate,Serializable{
/** Serial version UID */
private static final long serialVersionUID = -2407966402920578741L;
/** The transformer to call */
private final Transformer iTransformer;
/**
* Factory to create the predicate.
*
* @param
* the type that the predicate queries
* @param transformer
* the transformer to decorate
* @return the predicate
* @throws NullPointerException
* if the transformer is null
*/
public static Predicate transformerPredicate(final Transformer transformer){
if (transformer == null){
throw new NullPointerException("The transformer to call must not be null");
}
return new TransformerPredicate<>(transformer);
}
/**
* Constructor that performs no validation.
* Use transformerPredicate
if you want that.
*
* @param transformer
* the transformer to decorate
*/
public TransformerPredicate(final Transformer transformer){
super();
iTransformer = transformer;
}
/**
* Evaluates the predicate returning the result of the decorated transformer.
*
* @param object
* the input object
* @return true if decorated transformer returns Boolean.TRUE
* @throws FunctorException
* if the transformer returns an invalid type
*/
@Override
public boolean evaluate(final T object){
final Boolean result = iTransformer.transform(object);
if (result == null){
throw new FunctorException("Transformer must return an instanceof Boolean, it was a null object");
}
return result.booleanValue();
}
/**
* Gets the transformer.
*
* @return the transformer
* @since 3.1
*/
public Transformer getTransformer(){
return iTransformer;
}
}