How do I create an array of a generic type? (for use with NamedParameterJdbcTemplate)

Asked May 18 '15 at 18:02

Active May 18 '15 at 22:43

Viewed 127 times

NamedParameterJdbcTemplate in Spring has a method called batchUpdate which accepts a Map<String, ?>[] array as a parameter. How do I construct one of those?

Here are some examples of what I've tried doing:

Map<String, Object>[] rows = new Map<String, Object>[] { };

Map<String, Object>[] rows = new HashMap<String, Object>[] { };

List<Map<String, Object>> rowList = new ArrayList<>();
Map<String, Object>[] rows = rowList.toArray();

None of those work. How do I do it?

edited May 18 '15 at 18:47

Owen Pauling

9,864
18
50
58

asked May 18 '15 at 18:02

soapergem

7,597
16
79
124

1

What exactly do you mean when you say that none of these work? – Kevin Workman May 18 '15 at 18:03
@KevinWorkman - as in, that code will not compile. I get build errors. – soapergem May 18 '15 at 18:05
@azurefrog - I'm looking at the "possible duplicate" you posted but I honestly don't see a solution to my problem there. – soapergem May 18 '15 at 18:07
Also see http://stackoverflow.com/questions/217065/cannot-create-an-array-of-linkedlists-in-java – Radiodef May 18 '15 at 18:08
1

They are talking about within a generic method, but if you just replace the generic type with the concrete one you're trying to create it'll work. e.g. `Map[] rows = (Map[]) Array.newInstance(Map.class, arraySize);` compiles just fine. – azurefrog May 18 '15 at 18:09
@SoaperGEM If it's not compiling could you please post your build errors? – Captain Man May 18 '15 at 18:25
http://stackoverflow.com/a/8052827/2158288 – ZhongYu May 18 '15 at 18:40

How do I create an array of a generic type? (for use with NamedParameterJdbcTemplate)

0 Answers0