net.ontopia.persistence.rdbms.CSVExport.java Source code

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Here is the source code for net.ontopia.persistence.rdbms.CSVExport.java

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/*
 * #!
 * Ontopia Engine
 * #-
 * Copyright (C) 2001 - 2013 The Ontopia Project
 * #-
 * 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 net.ontopia.persistence.rdbms;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
import net.ontopia.persistence.proxy.DefaultConnectionFactory;
import net.ontopia.utils.CmdlineOptions;
import net.ontopia.utils.CmdlineUtils;
import org.apache.commons.lang3.StringUtils;

/** 
 * INTERNAL: Command line tool for exporting comma- or semicolon
 * separated files into a database.
 */

public class CSVExport {

    protected Connection conn;
    protected String separator = ";";

    public CSVExport(Connection conn) {
        this.conn = conn;
    }

    public void setSeparator(String separator) {
        this.separator = separator;
    }

    protected String escape(String value) {
        if (value == null)
            return "";
        else
            return value;
    }

    public void exportCSV(Writer writer, String table, String[] columns) throws SQLException, IOException {
        Statement stm = conn.createStatement();
        ResultSet rs = stm.executeQuery("select " + StringUtils.join(columns, ", ") + " from " + table);
        try {
            while (rs.next()) {
                for (int i = 1; i <= columns.length; i++) {
                    if (i > 1)
                        writer.write(separator);
                    writer.write('"');
                    String value = rs.getString(i);
                    if (value != null) {
                        writer.write(StringUtils.replace(value, "\"", "\\\""));
                    }
                    writer.write('"');
                }
                writer.write('\n');
            }
        } finally {
            rs.close();
            stm.close();
        }
        writer.flush();
    }

    public static void main(String[] argv) throws Exception {

        // Initialize logging
        CmdlineUtils.initializeLogging();

        // Initialize command line option parser and listeners
        CmdlineOptions options = new CmdlineOptions("CSVExport", argv);
        OptionsListener ohandler = new OptionsListener();

        // Register local options
        options.addLong(ohandler, "separator", 's', true);

        // Register logging options
        CmdlineUtils.registerLoggingOptions(options);

        // Parse command line options
        try {
            options.parse();
        } catch (CmdlineOptions.OptionsException e) {
            System.err.println("Error: " + e.getMessage());
            System.exit(1);
        }

        // Get command line arguments
        String[] args = options.getArguments();
        if (args.length < 3) {
            System.err.println("Error: wrong number of arguments.");
            usage();
            System.exit(1);
        }

        String dbprops = args[0];
        String table = args[1];
        String[] columns = StringUtils.split(args[2], ",");

        // Load property file
        Properties props = new Properties();
        props.load(new FileInputStream(dbprops));

        // Create database connection
        DefaultConnectionFactory cfactory = new DefaultConnectionFactory(props, true);
        Connection conn = cfactory.requestConnection();

        CSVExport ce = new CSVExport(conn);
        ce.setSeparator(ohandler.separator);
        //! ce.setUseQuotes(ohandler.usequotes);

        ce.exportCSV(new OutputStreamWriter(System.out), table, columns);
    }

    protected static void usage() {
        System.out.println(
                "java net.ontopia.persistence.rdbms.CSVExport [options] <dbprops> <csvfile> <table> <columns>");
        System.out.println("");
        System.out.println("  Tool for exporting tables into CSV files.");
        System.out.println("");
        System.out.println("  Options:");
        CmdlineUtils.printLoggingOptionsUsage(System.out);
        System.out.println("    --separator=<sep>: specifies the columns separator (default: ';')");
        System.out.println("");
        System.out.println("  <dbprops>: filename of database properties file");
        System.out.println("  <table>:  name of table to export");
        System.out.println("  <columns>:  ordered list of columns to export (comma-separated)");
    }

    private static class OptionsListener implements CmdlineOptions.ListenerIF {
        private String separator = ";";

        @Override
        public void processOption(char option, String value) throws CmdlineOptions.OptionsException {
            if (option == 's')
                separator = value;
        }
    }

}