Code convention about generic in Java

Question

It might be a very beginner question, but I'm curious to ask. Usually I use <T> to write a generic Java class.

public class Foo<T> extends Bar<T> {...}

But I also see people use <E> in many open source project. Does <E> imply anything different from <T>? Or it is just some coding habits?

it's just coding habits. some may say T stands for type and E stands for Entity, or whatever, you can use any letter you want. — Leo, Aug 09 '14 at 14:46

score 3 · Accepted Answer · edited Jun 20 '20 at 09:12

3

It doesn't make a difference, but these are the most common names:

http://docs.oracle.com/javase/tutorial/java/generics/types.html

The most commonly used type parameter names are:

E - Element (used extensively by the Java Collections Framework)

K - Key

N - Number

T - Type

V - Value

S,U,V etc. - 2nd, 3rd, 4th types

edited Jun 20 '20 at 09:12

Community

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answered Aug 09 '14 at 14:47

August

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score 2 · Answer 2 · edited Aug 09 '14 at 16:01

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<E> usually means an Element unlike <T> which means a Type. Check Generics here. This is just a convention.

edited Aug 09 '14 at 16:01

Peter O.

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answered Aug 09 '14 at 14:47

TheLostMind

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Code convention about generic in Java

2 Answers2