Lesson 5: Using Strings

Strings have always been and will always be special. That being said, the integration between Java and .NET is actually very simple.

In contrast to all other types, Java String is translated to C# string in the C# proxy types. This is a great convenience for you most of the time but has a few consequences that should almost never impact you.

On the plus side, you do not have to worry about converting a Java proxy String to a .NET string; the runtime does that for you automatically.

There are a couple of minuses:

• You lose access to the underlying Java String instance, which means you cannot perform any operations on it. This is hardly ever necessary and if it ever is, you could resort to runtime API methods to achieve your gaol.
• We always marshal and unmarshal strings between the .NET and Java side whenever they are used. This has a negative performance impact when compared with reusing a proxy String instance.

We carefully weighed the advantaged and disadvantages and decided that the benefits in terms of usability outweighed the costs, which were largely theoretical. As a consequence, you can use .NET strings in any place where a Java String or Object is expected.