org.hibernate.criterion.Junction.java Source code

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Here is the source code for org.hibernate.criterion.Junction.java

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/*
 * Hibernate, Relational Persistence for Idiomatic Java
 *
 * License: GNU Lesser General Public License (LGPL), version 2.1 or later.
 * See the lgpl.txt file in the root directory or <http://www.gnu.org/licenses/lgpl-2.1.html>.
 */
package org.hibernate.criterion;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;

import org.hibernate.Criteria;
import org.hibernate.HibernateException;
import org.hibernate.engine.spi.TypedValue;
import org.hibernate.internal.util.StringHelper;

/**
 * A sequence of a logical expressions combined by some
 * associative logical operator
 *
 * @author Gavin King
 * @author Steve Ebersole
 */
public class Junction implements Criterion {
    private final Nature nature;
    private final List<Criterion> conditions = new ArrayList<Criterion>();

    protected Junction(Nature nature) {
        this.nature = nature;
    }

    protected Junction(Nature nature, Criterion... criterion) {
        this(nature);
        Collections.addAll(conditions, criterion);
    }

    /**
     * Adds a criterion to the junction (and/or)
     *
     * @param criterion The criterion to add
     *
     * @return {@code this}, for method chaining
     */
    public Junction add(Criterion criterion) {
        conditions.add(criterion);
        return this;
    }

    public Nature getNature() {
        return nature;
    }

    /**
     * Access the conditions making up the junction
     *
     * @return the criterion
     */
    public Iterable<Criterion> conditions() {
        return conditions;
    }

    @Override
    public TypedValue[] getTypedValues(Criteria crit, CriteriaQuery criteriaQuery) throws HibernateException {
        final ArrayList<TypedValue> typedValues = new ArrayList<TypedValue>();
        for (Criterion condition : conditions) {
            final TypedValue[] subValues = condition.getTypedValues(crit, criteriaQuery);
            Collections.addAll(typedValues, subValues);
        }
        return typedValues.toArray(new TypedValue[typedValues.size()]);
    }

    @Override
    public String toSqlString(Criteria crit, CriteriaQuery criteriaQuery) throws HibernateException {
        if (conditions.size() == 0) {
            return "1=1";
        }

        final StringBuilder buffer = new StringBuilder().append('(');
        final Iterator itr = conditions.iterator();
        while (itr.hasNext()) {
            buffer.append(((Criterion) itr.next()).toSqlString(crit, criteriaQuery));
            if (itr.hasNext()) {
                buffer.append(' ').append(nature.getOperator()).append(' ');
            }
        }

        return buffer.append(')').toString();
    }

    @Override
    public String toString() {
        return '(' + StringHelper.join(' ' + nature.getOperator() + ' ', conditions.iterator()) + ')';
    }

    /**
     * The type of junction
     */
    public static enum Nature {
        /**
         * An AND
         */
        AND,
        /**
         * An OR
         */
        OR;

        /**
         * The corresponding SQL operator
         *
         * @return SQL operator
         */
        public String getOperator() {
            return name().toLowerCase(Locale.ROOT);
        }
    }
}