com.chadekin.jadys.syntax.orderby.impl.OrderByClauseBuilderImpl.java Source code

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Here is the source code for com.chadekin.jadys.syntax.orderby.impl.OrderByClauseBuilderImpl.java

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/**
 *                     GNU General Public License (GPL)
 *                        version 3.0, 29 June 2007
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/gpl-3.0.html>.
 *
 * Copyright (C) 2017 Marc Mamiah.
 * License GPLv3+: GNU GPL version 3
 */
package com.chadekin.jadys.syntax.orderby.impl;

import java.util.List;
import java.util.Set;
import java.util.function.Consumer;
import java.util.stream.Stream;
import com.chadekin.jadys.JadysSqlQueryBuilder;
import com.chadekin.jadys.commons.AbstractSqlQueryBuilder;
import com.chadekin.jadys.commons.enums.SqlLexical;
import com.chadekin.jadys.commons.resourcekeys.JadysKeys;
import com.chadekin.jadys.sqldialect.mysql.MySqlPostOrderBy;
import com.chadekin.jadys.syntax.orderby.OrderByClauseBuilder;
import com.google.common.collect.Lists;
import com.google.common.collect.Sets;
import org.apache.commons.lang.StringUtils;

/**
 * OrderByClauseBuilder
 */
public class OrderByClauseBuilderImpl<P> extends AbstractSqlQueryBuilder<OrderByClauseBuilder<P>>
        implements OrderByClauseBuilder<OrderByClauseBuilder<P>>, MySqlPostOrderBy<P> {

    private static final Set<String> SORTING_ORDER = Sets.newHashSet(SqlLexical.ASC.getCode(),
            SqlLexical.DESC.getCode());

    private List<String> columnsToOrder = Lists.newArrayList();

    protected OrderByClauseBuilderImpl(JadysSqlQueryBuilder parent) {
        super(parent);
    }

    public static <R> OrderByClauseBuilderImpl<R> newStatement(JadysSqlQueryBuilder parent) {
        return new OrderByClauseBuilderImpl<R>(parent);
    }

    @Override
    public SqlLexical getType() {
        return SqlLexical.ORDER_BY;
    }

    @Override
    public OrderByClauseBuilder append(String... expression) {
        if (expression != null && expression.length > 0) {

            Stream.of(expression).filter(value -> StringUtils.isNotBlank(value)).forEach(expressionConsumer());
        }
        return this;
    }

    private Consumer<String> expressionConsumer() {
        return value -> {
            extractAlias(value).stream().forEach(this::withAlias);

            String tempValue = null;
            if (SORTING_ORDER.contains(value) && !columnsToOrder.isEmpty()) {
                tempValue = columnsToOrder.stream()
                        .map(item -> new StringBuilder(item).append(JadysKeys.SPACE).append(value).toString())
                        .reduce((a, b) -> new StringBuilder(a).append(JadysKeys.COMMA).append(JadysKeys.SPACE)
                                .append(b).toString())
                        .orElse(StringUtils.EMPTY);
                columnsToOrder.clear();
            } else if (!SORTING_ORDER.contains(value)) {
                columnsToOrder.add(value);
            }
            if (StringUtils.isNotBlank(tempValue)) {
                if (getResultSql().length() > 0) {
                    getResultSql().append(JadysKeys.COMMA);
                }
                getResultSql().append(JadysKeys.SPACE).append(tempValue);
            }
        };
    }

    @Override
    public String buildNext() {
        columnsToOrder.stream().forEach(column_name -> {
            if (getResultSql().length() > 0) {
                getResultSql().append(JadysKeys.COMMA);
            }
            getResultSql().append(JadysKeys.SPACE).append(column_name);
        });
        return super.buildNext();
    }
}