DBIterator.java

package ezdb.rocksdb.util;

import java.io.Closeable;
import java.util.Iterator;
import java.util.Map;

//implementation taken from leveldbjni
/**
 * @author <a href="http://hiramchirino.com">Hiram Chirino</a>
 */
public interface DBIterator extends Iterator<Map.Entry<byte[], byte[]>>, Closeable {

    /**
     * Repositions the iterator so the key of the next BlockElement
     * returned greater than or equal to the specified targetKey.
     */
    public void seek(byte[] key);

    /**
     * Repositions the iterator so is is at the beginning of the Database.
     */
    public void seekToFirst();

    /**
     * Returns the next element in the iteration, without advancing the iteration.
     */
    public Map.Entry<byte[], byte[]> peekNext();

    /**
     * @return true if there is a previous entry in the iteration.
     */
    boolean hasPrev();

    /**
     * @return the previous element in the iteration and rewinds the iteration.
     */
    Map.Entry<byte[], byte[]> prev();

    /**
     * @return the previous element in the iteration, without rewinding the iteration.
     */
    public Map.Entry<byte[], byte[]> peekPrev();

    /**
     * Repositions the iterator so it is at the end of of the Database.
     */
    public void seekToLast();

}