class ExpressionVisitorBase<R> implements ExpressionVisitor<R> {

    private int queryLevel;

    @Override
    public ExpressionVisitorBase<R> incrementQueryLevel(int offset) {<FILL_FUNCTION_BODY>}

    public void setQueryLevel(int queryLevel) {
        this.queryLevel = queryLevel;
    }

    @Override
    public int getQueryLevel() {
        return queryLevel;
    }

    protected ExpressionVisitorBase<R> copy() {
        return this;
    }
}

        ExpressionVisitorBase<R> c = copy();
        c.setQueryLevel(getQueryLevel() + offset);
        return c;
    
<no_super_class>