ADBA Add type safe newFactory method

Mark Rotteveel mark at
Fri Jul 13 15:26:27 UTC 2018

The existing DataSourceFactory.newFactory(String name) has an unchecked 
cast using a (possibly inferred) type parameter.

Would it make sense to add an alternative with the signature:

public static <T extends DataSourceFactory> T newFactory(Class<T> clazz)

When you use this, you are tied to an ADBA implementation at compile 
time, but it will make this more type-safe.

And maybe the unchecked cast (and type parameter) should be removed from 
the variant taking a name only.

That is, change the method to

   public static DataSourceFactory newFactory(String name) {
     if (name == null) throw new 
IllegalArgumentException("DataSourceFactory name is null");
     return ServiceLoader
             .filter(p -> p.type().getName().equals(name))

Any casts would then be the explicit responsibility of the developer, 
instead of accidental due to type inference.

Mark Rotteveel

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