Add GenericConversionService with support for UUID and Strings

[nenaraab]

Motivation

As of now only acl_object_identity.object_id_identity of type java.util.Long are supported. In case you use identifiers of type java.lang.String or java.util.UUID the application needs to provide a ConversionService. This commit comes with two default Converters to support Strings and UUIDs.

related commit

pwheel@8efec02

related issue(s)

• ConversionService should be configurable for BasicLookupStrategy and JdbcAclService #4814
• Allow use of non-numeric (e.g. UUID) values for ObjectIdentity.getIdentifier() #4424

[jzheaux]

@nenaraab Thank you for addressing all these items. There are two that I think I miscommunicated on, so I've tried clarifying that in one more review.

Once you have this commit ready, would you squash your commits, please? Thanks again for the PR!

[nenaraab]

@jzheaux

Sorry, i was not sure how to correct a pull request best... If i would have squashed it, would it then look prettier, i.e. better readable for review?

The additional String identifier was introduced by intention, to make sure that the String2String (and not only LongAsString2String) conversion works as expected.

Thanks for your time, help and review :-)

[jzheaux]

@nenaraab Squashing helps with backpatches mostly, but yes it also helps a bit with the review process.

[nenaraab]

@jzheaux
In regard to your question with the DEFAULT_IDENTIFIER_AS_STRING...

Before I'v started with the code change, i created the test to simulate the issues i've seen within my application when not specifying any ConversionService.

Before of this pull request: this test case would have been green.

   @Test
   public void shouldReturnStringWhenStringClassIdType() throws SQLException {
      // given
      String identifier = DEFAULT_IDENTIFIER_AS_STRING;
      // when
      Serializable newIdentifier = aclClassIdUtils.identifierFrom(identifier, resultSet);
   ...
   }

...as “999” can be transformed to Long 999L. But the one below not:

   @Test
   public void shouldReturnStringWhenStringClassIdType() throws SQLException {
      // given
      String identifier = "MY_STRING_IDENTIFIER";
      // when
      Serializable newIdentifier = aclClassIdUtils.identifierFrom(identifier, resultSet);
      ....
   }

It gives me an java.lang.NumberFormatException: For input string: "MY_STRING_IDENTIFIER" because “MY_STRING_IDENTIFIER” can NOT be transformed to Long.

That's why i've decided to use a real "String" Identifier ...

[nenaraab]

So, the commits are squashed... anything else to change :-)

[jzheaux]

Thanks again, @nenaraab for the PR! This is now merged into master via 918a4cd where I edited the commit message for clarity.