Easiest way in Java to turn String into UUID

Question

How to generate a valid UUID from a String? The String alone is not what I'm looking for. Rather, I'm looking for something like a hash function converting any String to a valid UUID.

Well what are your requirements around uniqueness etc? You *could* just call `hashCode` to get an `int`, and then build a UUID based on that... but you'd obviously get a lot more collisions than necessary. — Jon Skeet, Sep 03 '14 at 05:56
What's in the string that has any relevance to a UUID at all? You may as well just generate a new UUID and keep a mapping table somewhere. Or possibly [`UUID.nameUUIDFromBytes(string.getBytes())`](http://docs.oracle.com/javase/7/docs/api/java/util/UUID.html#nameUUIDFromBytes(byte[])). — user207421, Sep 03 '14 at 06:01
There is a good answer on this here: https://stackoverflow.com/a/40230410/1174024 — Nicholas DiPiazza, Sep 17 '19 at 03:14

Raj · Answer 1 · 2019-02-19T21:04:51.603

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Try this out:

String superSecretId = "f000aa01-0451-4000-b000-000000000000";
UUID.fromString(superSecretId);

I am using this in my project and it works. Make sure you import the right stuff.

edited Feb 19 '19 at 21:04

answered Nov 02 '18 at 18:21

Raj

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This method only converts from a string representation of UUID to UUID. Does not work for any string. https://docs.oracle.com/javase/8/docs/api/java/util/UUID.html#toString-- – user0904 Jun 12 '19 at 13:43
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This is not what the op asked for. – Nicholas DiPiazza Sep 17 '19 at 00:36
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This doesn't hash __ANY__ string into an UUID – cdalxndr Feb 11 '21 at 13:27

Chris Martin · Answer 2 · 2014-09-08T18:05:07.080

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In the Java core library, there's java.util.UUID.nameUUIDFromBytes(byte[]).

I wouldn't recommend it because it's UUID 3 which is based on MD5, a very broken hash function. You'd be better off finding an implementation of UUID 5, which is based on SHA-1 (better although also sort of broken).

edited Sep 08 '14 at 18:05

answered Sep 03 '14 at 06:06

Chris Martin

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any js equivalent? – Abhijeet Ahuja Feb 01 '17 at 05:22
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@Abhijeet I wouldn't know. You may want to ask that as a separate question. – Chris Martin Feb 01 '17 at 05:24
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MD5 is broken for security purposes, but for hashing is good, has [low collision rate](https://stackoverflow.com/questions/201705/how-many-random-elements-before-md5-produces-collisions) – cdalxndr Feb 11 '21 at 13:38

Easiest way in Java to turn String into UUID

2 Answers2