public InventoryRecord readItem() throws Exception {
Connection connection = null;
PreparedStatement statement = null;
ResultSet rs = null;
try {
connection = ConnectionHelper.getConnection(dataSource);
statement = connection.prepareStatement(ConnectionHelper.SELECT_INVENTORY);
statement.setInt(1, 1);
rs = statement.executeQuery();
int quantity = -1;
while (rs.next()) {
quantity = rs.getInt("quantity");
}
// If we run out of items we are done so stop processing orders
if (quantity < 1) {
return null;
}
// decrement the quantity and update the table
InventoryRecord ir = new InventoryRecord(1, --quantity);
decrementInventory(connection, ir);
readerIndex++;
this.inventoryCheckpoint.setInventoryCount(readerIndex);
return new InventoryRecord(1, 1); // Every order only orders 1 item
} catch (SQLException e) {
throw e;
} finally {
ConnectionHelper.cleanupConnection(connection, rs, statement);
}
}
