// 获取一次交易中所有书本的名字, 以逗号隔开
private String getBookNames(Collection<BookSaleRecord> brs) {
if (brs.size() == 0) return "";
StringBuffer result = new StringBuffer();
for (BookSaleRecord br : brs) {
Book book = br.getBook();
result.append(book.getBOOK_NAME() + ", ");
}
// 去掉最后的逗号并返回
return result.substring(0, result.lastIndexOf(","));
}
@Override
public void saveRecord(SaleRecord record) {
// 遍历判断书的库存是否不够
for (BookSaleRecord r : record.getBookSaleRecords()) {
String bookId = r.getBook().getID();
Book b = bookDao.find(bookId);
// 当存库不够时,抛出异常
if (Integer.valueOf(r.getTRADE_SUM()) > Integer.valueOf(b.getREPERTORY_SIZE())) {
throw new BusinessException(b.getBOOK_NAME() + " 的库存不够");
}
}
// 先保存交易记录
String id = saleRecordDao.save(record);
// 再保存书的交易记录
for (BookSaleRecord r : record.getBookSaleRecords()) {
// 设置销售记录id
r.setT_SALE_RECORD_ID_FK(id);
bookSaleRecordDao.saveBookSaleRecord(r);
// 修改书的库存
String bookId = r.getBook().getID();
Book b = bookDao.find(bookId);
// 计算剩余的库存
int leave = Integer.valueOf(b.getREPERTORY_SIZE()) - Integer.valueOf(r.getTRADE_SUM());
// 设置库存并将库存数保存到数据库
b.setREPERTORY_SIZE(String.valueOf(leave));
bookDao.updateRepertory(b);
}
}