@Override
  @CheckForNull
  public Entry<K, V> firstEntry() {
    return Iterators.<@Nullable Entry<K, V>>getNext(entryIterator(), null);
  }

  @Override
  @CheckForNull
  public Entry<K, V> lastEntry() {
    return Iterators.<@Nullable Entry<K, V>>getNext(descendingEntryIterator(), null);
  }

  @Override
  @CheckForNull
  public Entry<K, V> pollFirstEntry() {

        final Map<String, String> params = new HashMap<String, String>();
        //final ExtractData text = extractor.getText(new ByteArrayInputStream(FileUtils.readFileToByteArray(new File(filePath))), params);
        final ExtractData text = extractor.getText(new ByteArrayInputStream(testStr.getBytes()), params);
        assertEquals(content, text.getContent());
    }

    // TODO other tests

                    break;
                case ST_GAP:
                    if( ch == ' ' || ch == '\t' ) {
                        break;
                    }
                    state = ST_EXT;
                case ST_EXT:
                    switch( ch ) {
                        case ' ':
                        case '\t':
                        case '\n':
                        case '#':

make
openssl
tk-dev
wget
xz-utils
zlib1g-dev
git

# Packages needed to build devtoolset
file
flex
g++
make
patch
rpm2cpio
unar
wget
xz-utils
cpio
gawk
texinfo

    @Resource
    protected ArchiveStreamFactory archiveStreamFactory;

    protected long maxContentSize = -1;

    @Override
    public ExtractData getText(final InputStream in, final Map<String, String> params) {
        if (in == null) {
            throw new CrawlerSystemException("The inputstream is null.");
        }

        extensionMap.put(inExt, outExt);
    }

    /*
     * (non-Javadoc)
     *
     * @see org.codelibs.fess.crawler.extractor.Extractor#getText(java.io.InputStream,
     * java.util.Map)
     */
    @Override
    public ExtractData getText(final InputStream in, final Map<String, String> params) {
        if (in == null) {
            throw new CrawlerSystemException("in is null.");
        }

    @Resource
    protected ArchiveStreamFactory archiveStreamFactory;

    protected long maxContentSize = -1;

    @Override
    public ExtractData getText(final InputStream in, final Map<String, String> params) {
        if (in == null) {
            throw new CrawlerSystemException("The inputstream is null.");
        }

import java.io.InputStream;
import java.util.Map;

import org.codelibs.fess.crawler.entity.ExtractData;

/**
 * @author shinsuke
 *
 */
public interface Extractor {

    ExtractData getText(InputStream in, Map<String, String> params);

    default int getWeight() {
        return 1;
    }

text/plain                     txt ini log in cfg m4 sh     # Plain Text File
text/richtext                  rtx              # Rich Text File
text/tab-separated-values      tsv              #
text/x-setext                  etx              #
text/x-sgml                    sgml sgm         # SGML Document
video/mpeg                     mpeg mpg mpe     # MPEG Movie File

     * @return request was handled asynchronously
     */
    boolean isResponseAsync ();


    /**
     * 
     * @return next chained message
     */
    @Override
    CommonServerMessageBlockRequest getNext ();


    /**
     * 
     * @return the following message
     */
    CommonServerMessageBlockRequest split ();


    /**
     * @return the size of this message
     */
    int size ();