libraries/sql-generator/src/main/java/org/apache/polygene/library/sql/generator/implementation/grammar/builders/query/GroupByBuilderImpl.java

/*
 *  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 org.apache.polygene.library.sql.generator.implementation.grammar.builders.query;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import org.apache.polygene.library.sql.generator.grammar.builders.query.GroupByBuilder;
import org.apache.polygene.library.sql.generator.grammar.query.GroupByClause;
import org.apache.polygene.library.sql.generator.grammar.query.GroupingElement;
import org.apache.polygene.library.sql.generator.implementation.grammar.common.SQLBuilderBase;
import org.apache.polygene.library.sql.generator.implementation.grammar.query.GroupByClauseImpl;
import org.apache.polygene.library.sql.generator.implementation.transformation.spi.SQLProcessorAggregator;

/**
 * @author Stanislav Muhametsin
 */
public class GroupByBuilderImpl extends SQLBuilderBase
    implements GroupByBuilder
{

    private final List<GroupingElement> _elements;

    public GroupByBuilderImpl( SQLProcessorAggregator processor )
    {
        super( processor );
        this._elements = new ArrayList<GroupingElement>();
    }

    public GroupByBuilder addGroupingElements( GroupingElement... elements )
    {
        Objects.requireNonNull( elements, "elements" );
        for( GroupingElement element : elements )
        {
            Objects.requireNonNull( element, "element" );
        }

        this._elements.addAll( Arrays.asList( elements ) );
        return this;
    }

    public List<GroupingElement> getGroupingElements()
    {
        return Collections.unmodifiableList( this._elements );
    }

    public GroupByClause createExpression()
    {
        return new GroupByClauseImpl( this.getProcessor(), this._elements );
    }
}