如何从列表中分配数字-JDBC JAVA SQL

Question

I am having trouble with my database where I want to select from a range of stock (not a primary key) and assign them to the users in the system.

For example, I have a field called stockCodes which consists of codes like CAB001-CAB100. This is not the primary key, and the primary key is in fact stockID.

The table looks like this...

ID | Stock Codes
--------------------
1  | CAB001-CAB100
2  | CBA100-CBA200

Now, how do I break down the stock codes so that I get a list like this in Java...

CAB001

CAB002

CAB003

CAB004

CAB005

...

Please help.

Answer 1

You would have to parse the text -- do they always follow the same format of 3 letters and 3 digits? If so, something to this effect would work:

/**
 * Populate a full list of stocks from a given range
 * 
 * @param stockRange the stock range pulled from the DB, in this format: "XXX###-XXX###"
 * @return list of all stocks in the specified range
 */
public List<String> getFullStockRange(final String stockRange) {
    final String[] values = stockRange.split("-"); 
    final Integer first = Integer.parseInt(values[0].substring(3));
    final Integer last = Integer.parseInt(values[1].substring(3));
    final String prefix = values[0].substring(0, 3);

    final List<String> list = new LinkedList<>();

    for (int i = first; i<= last; i++) {
        final String entry = String.format("%s%03d", prefix, i);
        list.add(entry);
    }

    return list;
}