Xtend vs Java

Lambdas are written like Smalltalk's blocks. If it's the last argument, it can go after the parentheses like Ruby's blocks. Parentheses on method calls are optional.

It uses Java's static type system, but you don't have to declare the type of everything all the time, since the Xtend compiler can usually figure it out. This also dramatically cuts down on Java's infamous verbosity.

Because Xtend relies heavily on JDK and Android classes, it runs just as fast as native Java code.

Xtend is a low-risk option. Because it compiles to human-readable Java, if you decide you don't like it for your project, you can just switch back to Java without losing your work.

This is where it gets its name. You can open classes and add new methods, kind of like Ruby. (Of course this has to be compiled to Java, so really it lives in a kind of helper class.)

Uses functional features ,which are very concise and idiomatic. Plus it has annotations, which cuts down on the Java boilerplate.

Methods are public if you don't specify, and fields are private. Locals declared with val in Xtend are final in Java. This dramatically cuts down on Java's infamous verbosity.

It makes it easy to debug and to read code.

The language and all its tools have enough time to age and they've aged well.

It is easier to catch errors sooner.