br.com.objectos.comuns.relational.jdbc.JdbcConfigure.java Source code

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Here is the source code for br.com.objectos.comuns.relational.jdbc.JdbcConfigure.java

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/*
 * Copyright 2011 Objectos, Fbrica de Software LTDA.
 *
 * Licensed 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 br.com.objectos.comuns.relational.jdbc;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.util.Collection;

import br.com.objectos.comuns.relational.search.Element;
import br.com.objectos.comuns.relational.search.OrderProperty;
import br.com.objectos.comuns.relational.search.SQLBuilder;
import br.com.objectos.comuns.relational.search.SelectColumns;
import br.com.objectos.comuns.relational.search.Where;

import com.google.common.base.Function;
import com.google.common.base.Functions;
import com.google.common.base.Joiner;
import com.google.common.collect.Collections2;

/**
 * @author marcio.endo@objectos.com.br (Marcio Endo)
 */
class JdbcConfigure {

    private final SQLBuilder sql;

    public JdbcConfigure(SQLBuilder sql) {
        this.sql = sql;
    }

    public PreparedStatement prepare(Connection connection) {
        try {

            StringBuilder sql = new StringBuilder();

            makeSql(sql);

            PreparedStatement stmt = connection.prepareStatement(sql.toString());

            CountingStatement countingStatement = new CountingStatement(stmt);
            Collection<Element> whereEls = getElements(Where.class);
            for (Element where : whereEls) {
                where.configure(countingStatement);
            }

            return stmt;

        } catch (SQLException e) {

            throw new SQLRuntimeException(e);

        }
    }

    private void makeSql(StringBuilder sql) {

        makeSelect(sql);

        makeWhere(sql);

        makeOrderBy(sql);

    }

    private void makeSelect(StringBuilder sql) {
        makeKey(sql, SelectColumns.class);
    }

    private void makeWhere(StringBuilder sql) {
        Collection<String> where = getStrings(Where.class);
        if (!where.isEmpty()) {
            sql.append("where ");
            String _where = Joiner.on(" and " + New.Line).join(where);
            sql.append(_where);
            sql.append(" " + New.Line);
        }
    }

    private void makeOrderBy(StringBuilder sql) {
        Collection<String> orders = validateAndGetStrings(OrderProperty.class);
        if (!orders.isEmpty()) {
            sql.append("order by ");
            String _orders = Joiner.on(", " + New.Line).join(orders);
            sql.append(_orders);
            sql.append(" " + New.Line);
        }
    }

    private void makeKey(StringBuilder sql, Class<?> key) {
        Collection<Element> els = getElements(key);

        for (Element el : els) {
            sql.append(el.toString());
        }
    }

    private Collection<Element> getElements(Class<?> keyClass) {
        return sql.getElements(keyClass);
    }

    private Collection<String> getStrings(Class<?> keyClass) {
        Collection<Element> els = sql.getElements(keyClass);
        return Collections2.transform(els, Functions.toStringFunction());
    }

    private Collection<String> validateAndGetStrings(Class<?> keyClass) {
        Collection<Element> els = sql.getElements(keyClass);
        return Collections2.transform(els, new ToString());
    }

    private class ToString implements Function<Element, String> {
        @Override
        public String apply(Element input) {
            return input.toString();
        }
    }

}