edu.harvard.iq.dataverse.ingest.metadataextraction.impl.plugins.fits.FITSFileMetadataExtractorSpi.java Source code

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Here is the source code for edu.harvard.iq.dataverse.ingest.metadataextraction.impl.plugins.fits.FITSFileMetadataExtractorSpi.java

Source

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package edu.harvard.iq.dataverse.ingest.metadataextraction.impl.plugins.fits;

import edu.harvard.iq.dataverse.ingest.metadataextraction.*;
import edu.harvard.iq.dataverse.ingest.metadataextraction.spi.*;

import java.io.*;
import java.nio.*;
import java.nio.channels.*;
import java.util.logging.*;
import java.util.Locale;

import static java.lang.System.*;

import org.apache.commons.codec.binary.Hex;

/**
 *
 * @author Leonid Andreev
 */
public class FITSFileMetadataExtractorSpi extends FileMetadataExtractorSpi {
    private static Logger dbgLog = Logger.getLogger(FITSFileMetadataExtractorSpi.class.getPackage().getName());
    private static int FITS_HEADER_SIZE = 10;
    private static String FITS_FILE_SIGNATURE = "SIMPLE  = ";

    private static String[] formatNames = { "fits", "fits" };
    private static String[] extensions = { "fits" };
    private static String[] mimeType = { "application/fits", "image/fits" };

    /**
     *
     */
    public FITSFileMetadataExtractorSpi() {
        super("HU-IQSS-DVN-project", "0.1", formatNames, extensions, mimeType,
                FITSFileMetadataExtractorSpi.class.getName());
        dbgLog.fine(FITSFileMetadataExtractorSpi.class.getName() + " is called");
    }

    public String getDescription(Locale locale) {
        return "HU-IQSS-DVN-project FITS File Ingester";
    }

    // (of the canDecodeInput methods below, the BufferedInputStream-based
    // one should be used);

    @Override
    public boolean canDecodeInput(Object source) throws IOException {
        out.println("this method is actually called: object");
        if (!(source instanceof BufferedInputStream)) {
            return false;
        } else if (source instanceof File) {
            out.println("source is a File object");
        } else {
            out.println("not File object");
        }
        if (source == null) {
            throw new IllegalArgumentException("source == null!");
        }

        BufferedInputStream stream = (BufferedInputStream) source;

        //

        return true;
    }

    @Override
    public boolean canDecodeInput(BufferedInputStream stream) throws IOException {
        if (stream == null) {
            throw new IllegalArgumentException("stream == null!");
        }

        byte[] b = new byte[FITS_HEADER_SIZE];

        if (stream.markSupported()) {
            stream.mark(0);
        }
        int nbytes = stream.read(b, 0, FITS_HEADER_SIZE);

        if (nbytes == 0) {
            throw new IOException();
        }
        //printHexDump(b, "hex dump of the byte-array");
        dbgLog.info("hex dump of the 1st " + FITS_HEADER_SIZE + " bytes:"
                + (new String(Hex.encodeHex(b))).toUpperCase());

        if (stream.markSupported()) {
            stream.reset();
        }

        boolean DEBUG = false;

        String hdr4fits = new String(b);

        if (hdr4fits.equals(FITS_FILE_SIGNATURE)) {
            dbgLog.fine("this is a fits file");
            return true;
        } else {
            dbgLog.fine("this is NOT a fits file");
            return false;
        }
    }

    @Override
    public boolean canDecodeInput(File file) throws IOException {
        if (file == null) {
            throw new IllegalArgumentException("file == null!");
        }
        if (!file.canRead()) {
            throw new IOException("cannot read the input file");
        }

        return true;
    }

    @Override
    public FileMetadataExtractor createIngesterInstance(Object ext) throws IOException {
        return new FITSFileMetadataExtractor(this);
    }
}