Java Two-Way Linked Set data-structure

Question

Is there an implementation of the following data-structure already implemented in Java:

Say I want the set for '2' ('A', 'C', 'D') but I also want the set for 'A' ('1', '2')

enter image description here

score 1 · Answer 1 · answered Nov 15 '13 at 13:50

1

You have no such data structure in the Java Collections Framework.

I suggest you the guava library you may find something useful there.

Note that what you have here is essentially a undirected graph so keep an eye out for graph libraries (for example JGraphT), or write your own.

answered Nov 15 '13 at 13:50

Adam Arold

1

Looks like a case for Guava's [BiMap](http://docs.guava-libraries.googlecode.com/git-history/release/javadoc/com/google/common/collect/BiMap.html) class. – Henrik Aasted Sørensen Nov 15 '13 at 13:51
2

@Henrik nope, that's 1:1 – Sean Patrick Floyd Nov 15 '13 at 13:52
This is a graph not a `BiMap` sadly. – Adam Arold Nov 15 '13 at 13:52
Well, a mythical mix of BiMap and MultiMap may be needed ... – Henrik Aasted Sørensen Nov 15 '13 at 13:55
That is not a good idea imho. It is not obvious only for the author of the code that he is using it as a graph. He should use a graph object for this. – Adam Arold Nov 15 '13 at 13:56
1

@Henrik @AdamArold `BiMultimap` whould do. Guava devs [closed issue requesting it](https://github.com/google/guava/issues/394) (they implemented it internally already), I guess risk of "graph semantics included" is one of reasons why they don't want to include it with general purpose library. – Xaerxess Jan 29 '15 at 13:16

1 Answers1