java - Generic Comparable gets a compiler error -

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• java generics - implements , extends 2 answers

i have code:

private class tree<t implements comparable<t>> { } 

i expect put string objects tree, , string implements comparable, looked @ first glance.

but i'm getting error:

> expected private class tree<t implements comparable<?>> {                     ^ 

suggestions?

you need use

private class tree<t extends comparable<t>> { }