Such as if I were to compare the Strings "Hello" and "World".
How does it know Hello is greater than World?
The only thing I can come up with is, maybe it uses the ASCII Table as reference?
Thanks for the help!
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2Have you looked at the [String API](http://docs.oracle.com/javase/7/docs/api/java/lang/String.html)? My bet is that much is to be found there. Edit, yep, I'm correct. It's all spelled out there, and that should be the first place you look for questions like these -- and definitely before asking this type of question here. – Hovercraft Full Of Eels Nov 02 '12 at 20:32
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Isn't "Hello" less than "World"? – Patrick James McDougle Nov 02 '12 at 20:33
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3It's explained in detail [here](http://docs.oracle.com/javase/7/docs/api/java/lang/String.html#compareTo%28java.lang.String%29). – Robert Harvey Nov 02 '12 at 20:38
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`"Hello"` is *less* than `"World"`, but `"hello"` is greater than `"World"` (upper vs. lower case). – Sergey Kalinichenko Nov 02 '12 at 20:40
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lol closed as localized but 27k views and actually helpful – Ungeheuer Nov 12 '16 at 05:55
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it compares two strings lexographically. check here in the String API.
If two strings are different, then either they have different characters at some index that is a valid index for both strings, or their lengths are different, or both. If they have different characters at one or more index positions, let k be the smallest such index; then the string whose character at position k has the smaller value, as determined by using the < operator, lexicographically precedes the other string.
Robert Harvey
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PermGenError
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All uppercase are preceding lowercase so:
"Be".compareTo("ay");
will return a negative value, which means "less-than".
Mordechai
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and what if I have more than 2 strings in list. How does comparison takes place? I mean index wise (0,1) (1,2) – Govinda Sakhare Mar 25 '16 at 10:16
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The code you've included returns "-31". `compareTo` returns the non-zero ASCII difference of the two strings. – Gaurang Tandon Feb 24 '17 at 04:01
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I always thought that *preceding* means that uppercase has a *higher* priority than lowercase which makes `"Be".compareTo("ay")>0` :( – He Yifei 何一非 May 01 '17 at 13:51
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@Arefly Yeah that's confusing, but if you look at it in terms of "less-than", "equals-to" and "greater-than" things are easier to remember. This is how it is described in the [Javadoc](https://docs.oracle.com/javase/8/docs/api/java/lang/Comparable.html#compareTo-T-). – Mordechai May 01 '17 at 18:17