Any Performance Optimization Tips for using NIO

[mars76]

Hi All,

I read that Java1.4.x has got java.nio packages which provides better performance when compared to the old IO Packages.

Can any one tell me which existing classes of IO Can be replaed with the classes in NIO packages !!

Thanks
Sateesh

[Joe Ess]

The java.io classes actually use the NIO classes behind the scenes, so there's no replacement to be done. Unless, of course, you need the NIO-specific functionality like non-blocking IO or file locking.

[Jim Yingst]

In most cases it's as Joe says. On big exception is - if you want to copy bytes to or from a file - use FileChannel's transferFrom() or transferTo() methods. They are faster (typically) and easier to use than doing the same thing with streams. Which is unusual - typically the NIO stuff is harder to use, and only sometimes is noticably faster. (But sometimes it's a lot faster, so it may be worth investigating.) Note that if you're reading from a file using JDK 5.0 (cough), you can often use a Scanner to get the best of both worlds - fast NIO access combined with ease of use.