Swing Hacks

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Chapter 11, Native Integration and Packaging

#84 Construct Single-Launch Applications

HACK

String track_name = track.name( );

String album_name = track.album( );

String artist_name = track.artist( );

com4j is a great open source project that unleashes the power of Java code

integrated with native applications. The iTunes COM interface provides

hooks for virtually everything that iTunes can do. These two things mean

you could write a program to sort songs, create new playlists, or even export

track listings to your own application that prints CD labels. You can find

fscom/sdk/itunescomsdk.html, so see what other cool things you can come up

with.

H A C K

#84

Construct Single-Launch Applications Hack #84

Only allow one instance of a program, notifying the existing instance when

the user tries to launch a new one.

Most graphical desktop applications are designed for multitasking. You start

your program to work on something, then switch to another program and

come back later. Oftentimes you’ll leave a large program, like a word pro-

cessor, running in the background to be used again when you need to open

another document, say an email attachment you received. When you click

on the attachment, your operating system won’t start a new instance of the

word processor; instead, it will send a message to the currently running

instance to open the new file—saving lots of system resources.

Java programs aren’t