writeBatch = function(batch) {
                log.msg('Writing ' + batch.length + ' items');
                w.write(
                    (firstWrite ? formatter.start : formatter.delimiter) +
                    batch.map(formatter.format).join(formatter.delimiter) +
                    (lastWrite ? formatter.end : '')
                );
                firstWrite = false;
            }
@name pjs.writers.base
@class Abstract base writer class
@private