StackOverflow2013

Note that there are some explanatory texts on larger screens.

plurals

PO
primarykey
Id
16516772
data
AcceptedAnswerId
0
AnswerCount
0
ClosedDate
CommentCount
0
CommunityOwnedDate
CreationDate
2013-05-13T07:23:59.470
FavoriteCount
0
LastActivityDate
2013-05-13T09:39:11.197
LastEditDate
2013-05-13T09:39:11.197
LastEditorUserId
2042841
OwnerUserId
2042841
ParentId
16516610
PostTypeId
2
Score
2
ViewCount
0
LastEditorDisplayName
text
Body
List is a generic interface, and the same interface regardless of the generic type. As such, all implementors are required to redefine all methods in it. As far as being able to add null into an "unbounded" list, it's not as much a matter of methods as much as a requisiste of respecting the interface: the unbound generic wildcard allows a reference to a List (or other generic class) to be passed around to methods without requiring a compile-time knowledge of the specific type it will contain. However, the contract of the generic must still be respected. This poses no big problem for read operations, since whatever is in the List, it will always (also) be a java.lang.Object. On the other hand, insert operations are almost impossible, since lacking informations about the accepted types, no type can be accepted - e.g. a List can only accept strings, but an Object could be anything else - a Number for example, and thus cannot be accepted safely. Null works safely since (assuming the List accept null values), it will be the only value that's always valid to be put inside the list (a null can be cast to any valid type). Edit: just since i noticed i didn't actually answer your question: yes, the <code><?></code> wildcard (and the extended forms as well <code><? extends X></code> and <code><? super X></code> are only valid when defining references, and cannot be used in generic instantiation.
Tags
Title
singulars
PostAcceptedAnswerId
1. This table or related slice is empty.
PostParentId
1. POIs the unbounded wildcard type used only to create references?
 singulars
 PostTypePostTypeId
 PTQuestion
PostTypePostTypeId
1. PTAnswer
UserLastEditorUserId
1. USGrim
UserOwnerUserId
1. USGrim
plurals
PostLinksPostIdRelatedPostId
1. This table or related slice is empty.
PostLinksRelatedPostIdPostId
1. This table or related slice is empty.
PostsAcceptedAnswerId
1. This table or related slice is empty.
PostsParentIdCreationDate
1. This table or related slice is empty.
VotesPostIdCreationDate
1. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
2. VO
 singulars
 PostPostId
 PO
 UserUserId
 This table or related slice is empty.
 VoteTypeVoteTypeId
 VTUpMod
CommentsPostId
1. This table or related slice is empty.

Querying!

Guidance

A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.