py.una.pol.karaku.util.KarakuReflectionUtils.java Source code

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Here is the source code for py.una.pol.karaku.util.KarakuReflectionUtils.java

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/*-
 * Copyright (c)
 *
 *       2012-2014, Facultad Politcnica, Universidad Nacional de Asuncin.
 *       2012-2014, Facultad de Ciencias Mdicas, Universidad Nacional de Asuncin.
 *       2012-2013, Centro Nacional de Computacin, Universidad Nacional de Asuncin.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301  USA
 */
package py.una.pol.karaku.util;

import java.lang.reflect.Field;
import java.lang.reflect.ParameterizedType;
import javax.annotation.Nonnull;
import org.springframework.util.ReflectionUtils;
import py.una.pol.karaku.exception.KarakuRuntimeException;

/**
 * Provee funcionalidades bsicas para utilizar Reflection.
 * 
 * @author Arturo Volpe
 * @since 2.2.8
 * @version 1.0 Nov 11, 2013
 * 
 */
public final class KarakuReflectionUtils {

    private KarakuReflectionUtils() {

    }

    /**
     * Retorna el tipo parmetrico implementado por <i>root</i> de un nivel de
     * jerarqua.
     * 
     * @param leaf
     *            clase raz (implementacin final)
     * @param index
     *            nmero de clase paramtrica
     * @return clase paramtrica.
     */
    @SuppressWarnings("unchecked")
    @Nonnull
    public static <T> Class<T> getParameterizedClass(@Nonnull Object leaf, int index) {

        ParameterizedType type = (ParameterizedType) leaf.getClass().getGenericSuperclass();

        if (type.getActualTypeArguments().length <= index) {
            throw new KarakuRuntimeException(
                    "Cant get the parameterizedClass of claas " + leaf.getClass().getName());
        }
        Class<T> clazz = (Class<T>) type.getActualTypeArguments()[index];
        if (clazz != null) {
            return clazz;
        } else {
            // no va a pasar.
            throw new KarakuRuntimeException(
                    "Cant get the parameterizedClass of claas " + leaf.getClass().getName());
        }
    }

    /**
     * Busca un {@link Field} por su nombre entre una lista de nombres.
     * 
     * <p>
     * Retorna el primer {@link Field} que encuentra, el orden de bsqueda es el
     * mismo que el vector de nombres.
     * </p>
     * 
     * @see ReflectionUtils#findField(Class, String)
     * @param base
     *            clase en la que se busca
     * @param names
     *            nombres de los mtodos
     * @return {@link Field} encontrado, <code>null</code> si no encuentra
     *         ninguno.
     */
    public static Field findField(@Nonnull Class<?> base, String... names) {

        Field f = null;
        for (String s : names) {
            f = ReflectionUtils.findField(base, s);
            if (f != null) {
                return f;
            }
        }
        return f;
    }
}