gda.device.detector.mythen.data.MythenSrsFileLoader.java Source code

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Here is the source code for gda.device.detector.mythen.data.MythenSrsFileLoader.java

Source

/*-
 * Copyright  2009 Diamond Light Source Ltd.
 *
 * This file is part of GDA.
 *
 * GDA is free software: you can redistribute it and/or modify it under the
 * terms of the GNU General Public License version 3 as published by the Free
 * Software Foundation.
 *
 * GDA 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 GDA. If not, see <http://www.gnu.org/licenses/>.
 */

package gda.device.detector.mythen.data;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Arrays;
import java.util.List;
import java.util.Vector;

import org.springframework.util.StringUtils;

/**
 * Loader for Mythen SRS files, where the filename of the Mythen data file is
 * recorded as a value.
 */
public class MythenSrsFileLoader {

    /**
     * Loads the specified SRS file, and returns the Mythen data files from it.
     * 
     * @param filename the SRS file
     * 
     * @return filenames of Mythen data files from the SRS file
     * 
     * @throws IOException
     */
    public String[] load(String filename) throws IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(filename)));
        return read(br);
    }

    protected String[] read(BufferedReader br) throws IOException {

        // skip through header
        String line = br.readLine();
        while (line != null && !line.contains("&END")) {
            line = br.readLine();
        }

        if (line == null) {
            throw new IOException("Reached end of file without seeing &END line");
        }

        // read data header; find column containing Mythen filenames
        String headerLine = br.readLine();
        if (!StringUtils.hasText(headerLine)) {
            throw new IOException("Didn't find column list");
        }
        List<String> headers = Arrays.asList(headerLine.split("\t"));
        int mythenColumn = headers.indexOf("mythen");
        if (mythenColumn == -1) {
            throw new IOException("Couldn't find 'mythen' column");
        }

        // read rest of data file; extract Mythen filename from each line
        List<String> filenames = new Vector<String>();
        while ((line = br.readLine()) != null) {
            String[] values = line.split("\t");
            String filenameValue = values[mythenColumn];
            filenames.add(filenameValue);
        }

        br.close();

        return filenames.toArray(new String[filenames.size()]);
    }

}