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/*
 *  streams library
 *
 *  Copyright (C) 2011-2014 by Christian Bockermann, Hendrik Blom
 * 
 *  streams is a library, API and runtime environment for processing high
 *  volume data streams. It is composed of three submodules "stream-api",
 *  "stream-core" and "stream-runtime".
 *
 *  The streams library (and its submodules) is free software: you can 
 *  redistribute it and/or modify it under the terms of the 
 *  GNU Affero General Public License as published by the Free Software 
 *  Foundation, either version 3 of the License, or (at your option) any 
 *  later version.
 *
 *  The stream.ai library (and its submodules) 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package stream.lookup;

import java.util.Map;

import stream.Data;
import stream.annotations.Parameter;
import stream.io.CsvStream;
import stream.io.SourceURL;

/**
 * 
 * An implementation of the AbstractDatabase lookup service, that reads data
 * from a CSV file at initialization time.
 * 
 * 
 * @author Christian Bockermann
 * 
 */
public class CsvDatabase extends AbstractDatabase {

	boolean header = true;
	String[] keys = null;
	String separator = "(;|,)";

	/**
	 * @see stream.lookup.AbstractDatabase#populateDatabase(stream.io.SourceURL,
	 *      java.util.Map)
	 */
	@Override
	protected void populateDatabase(SourceURL url, Map database)
			throws Exception {
		CsvStream stream = new CsvStream(url);
		stream.setHeader(isHeader());
		stream.setKeys(getKeys());
		stream.setSeparator(getSeparator());
		stream.init();
		readDatabase(stream, database);
		stream.close();
	}

	/**
	 * @return the header
	 */
	public boolean isHeader() {
		return header;
	}

	/**
	 * @param header
	 *            the header to set
	 */
	@Parameter(description = "Whether to use the first line as headers (keys/attribute names). ", required = false)
	public void setHeader(boolean header) {
		this.header = header;
	}

	/**
	 * @return the keys
	 */
	public String[] getKeys() {
		return keys;
	}

	/**
	 * @param keys
	 *            the keys to set
	 */
	@Parameter(description = "The keys of the CSV file. If not specified, the first line of the CSV will be used as keys.", required = false)
	public void setKeys(String[] keys) {
		this.keys = keys;
	}

	/**
	 * @return the separator
	 */
	public String getSeparator() {
		return separator;
	}

	/**
	 * @param separator
	 *            the separator to set
	 */
	@Parameter(description = "The separator string used for the CSV stream reading.", required = false)
	public void setSeparator(String separator) {
		this.separator = separator;
	}
}