RowIterator.java

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package org.hsqldb.navigator;

import org.hsqldb.Row;

/**
 *
 * @author Fred Toussi (fredt@users dot sourceforge.net)
 * @version 2.5.1
 * @since 1.7.2
 */
public interface RowIterator {

    RowIterator emptyRowIterator = new EmptyRowIterator();

    Object getField(int col);

    boolean next();

    Row getCurrentRow();

    Object[] getCurrent();

    void removeCurrent();

    void release();

    long getRowId();

    final class EmptyRowIterator implements RowIterator {

        private EmptyRowIterator() {}

        public Object getField(int col) {
            return null;
        }

        public boolean next() {
            return false;
        }

        public Row getCurrentRow() {
            return null;
        }

        public Object[] getCurrent() {
            return null;
        }

        public void release() {}

        public void removeCurrent() {}

        public long getRowId() {
            return 0L;
        }
    }
}