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Java Java Data Structures - Retired Exploring the Java Collection Framework Maps

Posted by Dinu Comendant
Dinu Comendant
6,049 Points

Why is it "for( Treet...)"

As far as I know, for loop starts with the type, for example "for (String str : arr)", but here in the for loop starts with the class Treet and I don't understand why

2 Answers

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

Every class is also a type. The name of the class is also the type of any of its instances.

Dinu Comendant
Dinu Comendant
6,049 Points
Dinu Comendant
Dinu Comendant
6,049 Points

So when do you need to use the class as the type instead of just using "String" and vice-versa? And is it common to use both concepts in actual coding?

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

You pick the type based on what you are going to do with the object. If it just holds text, you'd likely use a "String", But if it holds (for example) a set of student records, you'd probably use a "StudentInfo" class (assuming one had been defined already).