Does Java have an equivalent variable type to C#'s Tuple?

Question

I am translating a program from C# to Java. In the C# code, the developer uses Tuple. I need to translate this C# code into Java code. Therefore, does Java have an equivalent variable type to C#'s Tuple?

Answer 1

Due to type erasure, there is no way in Java to have exact mirrors of the various Tuple classes in .NET. However, here is a BSD-licensed implementation of Tuple2 and Tuple3 for Java, which mirror the Tuple<T1, T2> and Tuple<T1, T2, T3> types from .NET.

• Tuple.java (static methods to construct tuples with type inference)
• Tuple2.java
• Tuple3.java

One cool thing you can do in Java but not C# is this:

class Bar extends Foo { }

...

Tuple2<? extends Foo, ? extends Foo> tuple = Tuple.create(new Bar(), new Bar());

In C#, you would have to use casts instead:

Tuple<Foo, Foo> tuple = Tuple.Create((Foo)new Bar(), (Foo)new Bar());

Answer 2

I was in need of Tuple equivalent in my android project as well, but didn't found any native solution in Java. But surprisingly there is Pair.class in android's util which is exact what I was searching for.

So Android developers, who came across this question, use Pair.class in android.util package.

P.S. I'm sad to accept that there are a lot of things that Java is far behind from other languages already.