public boolean previous() throws SQLException {
        checkState();

        boolean b = rs.previous();
        notifyCursorMoved();
        return b;
    }
Moves the cursor to the previous row in this
<code>ResultSet</code> object.

<p><B>Note:</B> Calling the method <code>previous()</code> is not the same as
calling the method <code>relative(-1)</code> because it
makes sense to call <code>previous()</code> when there is no current row.

@return <code>true</code> if the cursor is on a valid row;
<code>false</code> if it is off the result set
@throws SQLException if (1) a database access error occurs,
           (2) the result set type is <code>TYPE_FORWARD_ONLY</code>,
           or (3) this rowset does not currently have a valid
           connection, prepared statement, and result set
src/main/java/org/replicadb/rowset/sun/rowset/JdbcRowSetImpl.java