jongo.sql.dialect.H2Dialect.java Source code

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Here is the source code for jongo.sql.dialect.H2Dialect.java

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/**
 * Copyright (C) 2011, 2012 Alejandro Ayuso
 *
 * This file is part of Jongo.
 * Jongo 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
 * any later version.
 * 
 * Jongo 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 Jongo.  If not, see <http://www.gnu.org/licenses/>.
 */
package jongo.sql.dialect;

import jongo.jdbc.LimitParam;
import jongo.jdbc.OrderParam;
import jongo.sql.Delete;
import jongo.sql.DynamicFinder;
import jongo.sql.Insert;
import jongo.sql.Select;
import jongo.sql.Update;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Dialect for H2 RDBMS.
 * @author samarjit samanta
 */
public class H2Dialect extends SQLDialect {

    private static final Logger l = LoggerFactory.getLogger(OracleDialect.class);

    @Override
    public String toStatementString(Insert insert) {
        if (insert.getColumns().isEmpty())
            throw new IllegalArgumentException("An insert query can't be empty");

        final StringBuilder b = new StringBuilder("INSERT INTO ");
        b.append(insert.getTable().getDatabase()).append(".");
        b.append(insert.getTable().getName());
        if (!insert.getColumns().isEmpty()) {
            b.append(" (");
            b.append(StringUtils.join(insert.getColumns().keySet(), ","));
            b.append(") VALUES (");
            b.append(StringUtils.removeEnd(StringUtils.repeat("?,", insert.getColumns().size()), ","));
            b.append(")");
        }
        l.debug(b.toString());
        return b.toString();
    }

    @Override
    public String toStatementString(Update update) {
        if (update.getColumns().isEmpty())
            throw new IllegalArgumentException("An update query can't be empty");

        final StringBuilder b = new StringBuilder("UPDATE ");
        b.append(update.getTable().getDatabase()).append(".");
        b.append(update.getTable().getName()).append(" SET ");

        for (String k : update.getColumns().keySet()) {
            b.append(update.getTable().getName()).append(".");
            b.append(k);
            b.append("=?,");
        }

        b.deleteCharAt(b.length() - 1);
        b.append(" WHERE ");
        b.append(update.getTable().getName()).append(".");
        b.append(update.getTable().getPrimaryKey()).append("=?");
        l.debug(b.toString());
        return b.toString();
    }

    @Override
    public String toStatementString(Delete delete) {
        final StringBuilder b = new StringBuilder("DELETE FROM ");
        b.append(delete.getTable().getDatabase()).append(".");
        b.append(delete.getTable().getName());
        b.append(" WHERE ");
        b.append(delete.getTable().getName()).append(".");
        b.append(delete.getTable().getPrimaryKey()).append("=?");
        l.debug(b.toString());
        return b.toString();
    }

    @Override
    public String toStatementString(Select select) {
        final StringBuilder b = new StringBuilder("SELECT ");
        if (select.isAllColumns()) {
            b.append("*");
        } else {
            String cols = StringUtils.join(select.getColumns(), ",");
            b.append(cols);
        }
        b.append(" FROM ").append(select.getTable().getName());
        if (!select.isAllRecords()) {
            b.append(" WHERE ").append(select.getParameter().getColumnName()).append(" ")
                    .append(select.getParameter().getOperator().sql()).append(" ?");
        }
        if (select.getOrderParam() != null)
            b.append(" ORDER BY ").append(select.getOrderParam().toString());

        if (select.getLimitParam() != null)
            b.append(" LIMIT ").append(select.getLimitParam().getLimit()).append(" OFFSET ")
                    .append(select.getLimitParam().getStart());

        l.debug(b.toString());
        return b.toString();
    }

    @Override
    public String toStatementString(DynamicFinder finder, LimitParam limit, OrderParam order) {
        if (finder == null || limit == null || order == null)
            throw new IllegalArgumentException("Invalid argument");

        final String[] parts = finder.getSql().split("WHERE");
        final StringBuilder query = new StringBuilder("SELECT * FROM ( SELECT ROWnum ");
        //        query.append(finder.getTable()).append(".").append(order.getColumn());
        //        query.append(" ");
        query.append(order.getDirection());
        query.append("   AS ROW_NUMBER, ");
        query.append(finder.getTable());
        query.append(".* FROM ");
        query.append(finder.getTable());
        query.append(" WHERE ");
        query.append(parts[1]);
        query.append(" ) WHERE ROW_NUMBER BETWEEN ");
        query.append(limit.getStart());
        query.append(" AND ");
        query.append(limit.getLimit());
        return query.toString();
    }

    @Override
    public String listOfTablesStatement() {
        return "SELECT TABLE_NAME FROM INFORMATION_SCHEMA.TABLES  WHERE table_type = 'TABLE'";
    }

}