Swing Hacks

Control iTunes on Mac OS X #82

Chapter 11, Native Integration and Packaging

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HACK

so what better way to show off the power of Java than by taking control of

iTunes directly from your own Java app!

The task of dealing with native applications is, by nature, platform specific.

For example, though Apple ships identical looking copies of iTunes for both

Windows and Mac, the integration APIs couldn’t be more different.

Apple Events

Most well-written Mac OS X applications support an API called Apple

Events. Apple Events let a programmer send commands and requests to a

running application from another program, through a process often called

scripting. The application must be written to support Apple Events and

every scriptable feature must be defined explicitly when the program is writ-

ten. Since it was Apple that wrote iTunes, they did a very good job of expos-

ing virtually every feature through Apple Events. All you need to do is tap

into these events.

Apple Events is an API, and you need a programming language to support it.

There are a variety of languages to choose from, but the easiest one to start

with is AppleScript, as the syntax is simple and OS X ships with a command-

line interpreter. There are also direct Java bindings available, but for the

kinds of simple things you are likely to want to do with iTunes,

exec( )ing

the interpreter will be much easier. All you have to do is call

osascript ...