java - Generic Comparable gets a compiler error -


this question has answer here:

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>> { }

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