br.com.suricattus.surispring.hibernate.criterion.HQL.java Source code

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Here is the source code for br.com.suricattus.surispring.hibernate.criterion.HQL.java

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/*
 * SURICATTUS
 * Copyright 2011, SURICATTUS CONSULTORIA LTDA, 
 * and individual contributors as indicated by the @authors tag
 *
 * This 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 software 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 software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package br.com.suricattus.surispring.hibernate.criterion;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.hibernate.Query;
import org.hibernate.Session;

/**
 * Classe manipuladora de HQL.
 * 
 * @author Lucas Lins
 *
 */
public class HQL {

    private Session session;

    private List<String> select;
    private List<String> from;
    private List<String> where;
    private Map<String, Object> params;
    private List<String> group;
    private List<String> order;

    private Integer firstResult;
    private Integer maxResults;

    public HQL(Session session) {
        this.session = session;
        this.select = new ArrayList<String>();
        this.from = new ArrayList<String>();
        this.where = new ArrayList<String>();
        this.params = new HashMap<String, Object>();
        this.group = new ArrayList<String>();
        this.order = new ArrayList<String>();
    }

    public void addToSelect(String select) {
        this.select.add(select);
    }

    public void addToFrom(String from) {
        this.from.add(from);
    }

    public void addToWhere(String where) {
        this.where.add(where);
    }

    public void addParam(String paramName, Object paramValue) {
        this.params.put(paramName, paramValue);
    }

    public void addToGroup(String group) {
        this.group.add(group);
    }

    public void addToOrder(String order) {
        this.order.add(order);
    }

    public void setFirstResult(Integer firstResult) {
        this.firstResult = firstResult;
    }

    public void setMaxResults(Integer maxResults) {
        this.maxResults = maxResults;
    }

    @SuppressWarnings("unchecked")
    public <T> List<T> list(Class<T> resultType) {
        return (List<T>) getQuery().list();
    }

    @SuppressWarnings("unchecked")
    public <T> T uniqueResult(Class<T> resultType) {
        return (T) getQuery().uniqueResult();
    }

    public Object uniqueResult() {
        return getQuery().uniqueResult();
    }

    @SuppressWarnings("rawtypes")
    private Query getQuery() {

        StringBuilder hql = new StringBuilder();

        if (!select.isEmpty())
            append(hql, "select", select, ",");
        append(hql, "from", from);
        if (!where.isEmpty())
            append(hql, "where", where, "and");
        if (!group.isEmpty())
            append(hql, "group by", group, ",");
        if (!order.isEmpty())
            append(hql, "order by", order, ",");

        Query query = session.createQuery(hql.toString());

        for (String paramName : params.keySet()) {
            Object param = params.get(paramName);
            if (param instanceof Collection) {
                query.setParameterList(paramName, (Collection) params.get(paramName));
            } else if (param instanceof Object[]) {
                query.setParameterList(paramName, (Object[]) params.get(paramName));
            } else {
                query.setParameter(paramName, params.get(paramName));
            }
        }

        if (firstResult != null)
            query.setFirstResult(firstResult);
        if (maxResults != null)
            query.setMaxResults(maxResults);

        return query;
    }

    private void append(StringBuilder sb, String part, List<?> values, String separator) {
        append(sb, part);
        for (int i = 0; i < values.size(); i++) {
            append(sb, values.get(i));
            if (i != (values.size() - 1))
                append(sb, separator);
            sb.append(" ");
        }
    }

    private void append(StringBuilder sb, String part, List<?> values) {
        append(sb, part);
        for (Object value : values)
            append(sb, value);
    }

    private void append(StringBuilder sb, Object value) {
        sb.append(value);
        sb.append(" ");
    }

}