InfoQ对 Joshua Bloch 访问

What is Google doing with Java?

Google uses Java in many places. We use it a lot in the middle tier obviously on the client, we use Ajax, we use Javascript and typically a lot of the applications that we use everyday like GMail, Google calendar, talk directly to Java and then the data is often stored on a back-end that's written in C++; we also use Java for our ads frontend server which is a very important part of our infrastructure, as you know ads are an important part of the engine that makes Google go. We use them a lot for internal applications. To make all this work we have a fairly large piece of Java infrastructure and that's my job at Google, I maintain that infrastructure.

Can you tell us more about this awesome Java infrastructure at Google?

There's a lot of classical google infrastructure. If you were at the Trundheim open house at Oslo last night, but the director discussed three of the main pieces of infrastructure google has: google file system, map reduce and big table and all these things were written in C++. But my team has made them accessible from Java in some cases, by re-implementing parts of them and in some cases by writing Java layers that talk to them through native methods and all that has proven quite successful. So now one can write all this core Google infrastructure in Java and additionally we have a lot of JDK-like stuff of our own invention and some of it we intend to submit for possible inclusion in the JDK. We have already done a little bit of it. Earlier I was referring to a this ArrayDeck class and that came out of some code that I wrote at google. There's a guy Kevin Burley who has written a lot of good stuff that I hope to see in Java 7. For example he wrote a facility called TimeLimiter which is a really cool thing. You take an interface and an implementation of that interface and it returns another implementation that delegates to the written original implementation and it time limits the calls and if they time out an unchecked time-out exception is thrown in the calling thread, so it allows you without the hassle of managing your own executor and your own futures and it works out really nice.

Ref:
http://www.infoq.com/interviews/joshua-bloch