private static final String KEEP_EXPIRES_DOCS = "keep_expires_docs";

    protected long crawlingExecutionInterval = Constants.DEFAULT_CRAWLING_EXECUTION_INTERVAL;

    protected int crawlerPriority = Thread.NORM_PRIORITY;

    protected final List<DataCrawlingThread> dataCrawlingThreadList = Collections.synchronizedList(new ArrayList<>());

    public void crawl(final String sessionId) {

            }
            bulkRequestBuilder = null;
        }
    }

    public int getPriority() {
        return this.priority;
    }

    public void setPriority(final int priority) {
        this.priority = priority;
    }

    public void setRequestTimeout(final String bulkRequestTimeout) {
        this.requestTimeout = bulkRequestTimeout;
    }

        assertEquals(2, ingesters[1].getPriority());
        assertEquals(3, ingesters[2].getPriority());
    }

    private static class TestIngester extends Ingester {
        public TestIngester(int priority) {
            this.priority = priority;
        }
    }

import org.codelibs.fess.util.ComponentUtil;

public abstract class Ingester {

    protected int priority = 99;

    public int getPriority() {
        return priority;
    }

    public void setPriority(final int priority) {
        this.priority = priority;
    }

    public void register() {
        ComponentUtil.getIngestFactory().add(this);
    }

    // web/file

        }
        final Ingester[] newIngesters = Arrays.copyOf(ingesters, ingesters.length + 1);
        newIngesters[ingesters.length] = ingester;
        Arrays.sort(newIngesters, (o1, o2) -> o1.priority - o2.priority);
        ingesters = newIngesters;
    }

    public Ingester[] getIngesters() {
        return ingesters;
    }

    protected long crawlingExecutionInterval = Constants.DEFAULT_CRAWLING_EXECUTION_INTERVAL;

    protected int indexUpdaterPriority = Thread.MAX_PRIORITY;

    protected int crawlerPriority = Thread.NORM_PRIORITY;

    protected final List<Crawler> crawlerList = Collections.synchronizedList(new ArrayList<>());