如一下代码中 public List<Product> findProduct(int start, int pageSize) 。。。{ ...return XX;} XX的类型一定要和前面的返回值类型一致。
public List<Product> findProduct(int start, int pageSize)
throws SQLException {
QueryRunner qr = new QueryRunner(DataSourceUtils.getDataSource());
String sql = "select * from product limit ?,?";
return qr.query(sql, new BeanListHandler<Product>(Product.class),
start, pageSize);
}
// 总数
public int findTotalCount() throws SQLException {
QueryRunner qr = new QueryRunner(DataSourceUtils.getDataSource());
String sql = "select count(*) from product";
return ((Long) qr.query(sql, new ScalarHandler())).intValue();
}
// 保存
public int addProduct(Product product) throws SQLException {
String sql = "insert into Product values(?,?,?,?,?,?,?,?,?,?)";
QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());
// 返回值 int代表影响的行数
return runner.update(sql, product.getPid(), product.getPname(), product
.getMarket_price(), product.getShop_price(), product
.getPimage(), new SimpleDateFormat("yyyy-MM-dd HH:mm:ss")
.format(product.getPdate()), product.getIs_hot(), product
.getPdesc(), product.getPflag(), product.getCid());
}
// 删除数据库的记录
public int deleteProduct(String pid) throws SQLException {
String sql = "delete from product where pid=?";
QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());
return runner.update(sql, pid);
}
// 查询单个product对象
public Product findProductByPid(String pid) throws SQLException {
String sql = "select * from product where pid=?";
QueryRunner qr = new QueryRunner(DataSourceUtils.getDataSource());
Product product = qr.query(sql,
new BeanHandler<Product>(Product.class), pid);
return product;
}
// 修改
public int updateProduct(Product product) throws SQLException {
{
QueryRunner runner = new QueryRunner(
DataSourceUtils.getDataSource());
if (product.getPimage() == null) {
String sql = "update product set pname=?,market_price=?,shop_price=?,"
+ "is_hot=?,pdesc=?,pflag=?,cid=? where pid=?";
return runner.update(sql, product.getPname(),
product.getMarket_price(), product.getShop_price(),
product.getIs_hot(), product.getPdesc(),
product.getPflag(), product.getCid(), product.getPid());
} else {
String sql = "update product set pname=?,market_price=?,shop_price=?,"
+ "pimage=?,is_hot=?,pdesc=?,pflag=?,cid=? where pid=?";
return runner.update(sql, product.getPname(),
product.getMarket_price(), product.getShop_price(),
product.getPimage(), product.getIs_hot(),
product.getPdesc(), product.getPflag(),
product.getCid(), product.getPid());
}
}
}