de.dbload.csv.writer.ResourceWriter.java Source code

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Here is the source code for de.dbload.csv.writer.ResourceWriter.java

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/*
 * Copyright 2014 Andre Winkler
 * 
 * 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 de.dbload.csv.writer;

import java.io.BufferedOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.Writer;
import java.nio.charset.Charset;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.StandardOpenOption;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Timestamp;
import java.util.Date;

import org.joda.time.DateTime;

import de.dbload.impl.DbloadException;
import de.dbload.meta.ColumnMetaData;
import de.dbload.meta.ColumnMetaData.Type;
import de.dbload.misc.DateTimeUtils;

/**
 * Write some SQL results to a <code>.dat</code> file.
 *
 * @author Andre Winkler. http://www.andre-winkler.de
 */
public class ResourceWriter {

    private final File file;
    private final Charset utf8;

    public ResourceWriter(Path _path) {
        this(_path.toFile());
    }

    public ResourceWriter(File _file) {
        file = _file;
        utf8 = Charset.forName("UTF-8");
    }

    public void start(Connection conn, String sqlSelect, boolean append) throws SQLException {

        if (append) {
            if (!file.exists()) {
                try {
                    file.createNewFile();
                } catch (IOException ex) {
                    throw new DbloadException("Unable to create export file.", ex);
                }
            }
        } else {
            if (file.exists()) {
                file.delete();
            }
        }

        try (OutputStream out = new BufferedOutputStream(Files.newOutputStream(file.toPath(),
                append ? StandardOpenOption.APPEND : StandardOpenOption.CREATE));
                Writer writer = new OutputStreamWriter(out, utf8)) {

            PrintWriter pw = new PrintWriter(writer, true);
            try (Statement stmt = conn.createStatement(); ResultSet resultSet = stmt.executeQuery(sqlSelect)) {

                ResultSetMetaData metaData = resultSet.getMetaData();

                pw.print("### TAB ");
                pw.println(metaData.getTableName(1));
                pw.print("### ");

                for (int i = 1; i <= metaData.getColumnCount(); i++) {
                    pw.print(metaData.getColumnName(i));
                    if (i < metaData.getColumnCount()) {
                        pw.print(" | ");
                    }
                }
                pw.println();

                while (resultSet.next()) {
                    for (int i = 1; i <= metaData.getColumnCount(); i++) {

                        String print = null;
                        int type = resultSet.getMetaData().getColumnType(i);
                        Type columnType = ColumnMetaData.Type.valueOf(type);
                        switch (columnType) {
                        case DATE:
                        case TIME:
                        case DATE_TIME:
                            Timestamp timestamp = resultSet.getTimestamp(i);
                            if (timestamp == null) {
                                print = "";
                            } else {
                                Date date = new Date(timestamp.getTime());
                                DateTime dateTime = new DateTime(date);
                                print = dateTime.toString(DateTimeUtils.DATE_FORMAT);
                            }
                            break;
                        default:
                            print = resultSet.getString(i);
                        }

                        if (print == null) {
                            pw.print("");
                        } else {
                            pw.print(print);
                        }

                        if (i < metaData.getColumnCount()) {
                            pw.print(" | ");
                        }
                    }
                    pw.println();
                }
                pw.println();
            }
        } catch (IOException ex) {
            throw new DbloadException(ex);
        }
    }

}