py.una.pol.karaku.dao.entity.interceptors.UriInterceptor.java Source code

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Here is the source code for py.una.pol.karaku.dao.entity.interceptors.UriInterceptor.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.dao.entity.interceptors;

import static py.una.pol.karaku.util.Checker.notNull;
import java.lang.reflect.Field;
import java.math.BigInteger;
import javax.annotation.Nonnull;
import org.apache.commons.lang3.Validate;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.util.ReflectionUtils;
import py.una.pol.karaku.dao.entity.Operation;
import py.una.pol.karaku.dao.entity.annotations.URI;
import py.una.pol.karaku.util.StringUtils;

/**
 * Intercepta los atributos con la anotacin {@link URI} y genera
 * automaticamente las mismas.
 * 
 * @author Arturo Volpe
 * @since 2.2.8
 * @version 1.0 Nov 5, 2013
 * 
 */
@Component
public class UriInterceptor extends AbstractInterceptor {

    @Autowired
    private SessionFactory factory;

    @Override
    public Class<?>[] getObservedTypes() {

        return new Class<?>[] { String.class };
    }

    @Override
    public Class<?>[] getObservedAnnotations() {

        return new Class<?>[] { URI.class };
    }

    @Override
    public boolean interceptable(Operation op, Field field, Object bean) {

        return op == Operation.CREATE;
    }

    @Override
    public void intercept(Operation op, Field field, Object bean) {

        URI uri = notNull(field.getAnnotation(URI.class), "Intercept a field without uri in UriInterceptor");

        String baseUri = Validate.notNull(uri.baseUri(), "Base uri in a @URI is null or empty");

        String finalUri = null;
        switch (uri.type()) {
        case FIELD:
            finalUri = byUniqueField(field, bean, uri);
            break;
        case SEQUENCE:
            finalUri = bySequence(field, uri);
            break;
        default:
            throw new IllegalArgumentException();
        }

        ReflectionUtils.setField(field, bean, baseUri + finalUri);

    }

    private String bySequence(Field f, URI uri) {

        Validate.validState(StringUtils.isValid(uri.sequenceName()),
                "URI with type Sequence without sequence name %s", f.getName());

        return getNextSequence(uri.sequenceName());
    }

    private String byUniqueField(Field f, @Nonnull Object bean, URI uri) {

        String field = notNull(uri.field(), "URI with type Field without atribute name %s", f.getName());

        Object fieldValue = notNull(getFieldValueOfBean(bean, field), "The unique field %s, is null or empty",
                f.getName());

        Validate.validState(StringUtils.isValid(fieldValue.toString()), "The unique field %s is invalid (%s)",
                f.getName(), fieldValue);

        return fieldValue.toString().trim().replace(' ', '_');
    }

    protected String getNextSequence(String sequenceName) {

        BigInteger nextVal = (BigInteger) getSession()
                .createSQLQuery(String.format("select nextval('%s');", sequenceName)).uniqueResult();
        return "" + nextVal.longValue();
    }

    protected Session getSession() {

        return factory.getCurrentSession();
    }
}