I recently bought a MacBook Pro (2 GHz Intel Core i7 with 64-bit kernel and extensions enabled) to develop with Java. First thing to do was updating Java and installing Eclipse IDE, but everything about Eclipse was very slow. So I started googling and found the solution here:

http://www.eclipse.org/forums/index.php?t=tree&th=205238 The problem was related to 64-bit, Java and Eclipse are ready for working on 64-bit but you have to configure them. Then, open eclipse.ini and update of this way (lines updated are 12, 16, 19, 20 and 21):

[sourcecode language=”text” gutter=”true” wraplines=”false” highlight=”12,16,19,20,21”]
-startup
../../../plugins/org.eclipse.equinox.launcher_1.1.1.R36x_v20101122_1400.jar
--launcher.library
../../../plugins/org.eclipse.equinox.launcher.cocoa.macosx.x86_64_1.1.2.R36x_v20101019_1345
-product
org.eclipse.epp.package.jee.product
--launcher.defaultAction
openFile
-showsplash
org.eclipse.platform
--launcher.XXMaxPermSize
512m
--launcher.defaultAction
openFile
-vmargs
-Dosgi.requiredJavaVersion=1.6
-XstartOnFirstThread
-Dorg.eclipse.swt.internal.carbon.smallFonts
-XX:MaxPermSize=512m
-Xms80m
-Xmx1024m
-Xdock:icon=../Resources/Eclipse.icns
-XstartOnFirstThread
-Dorg.eclipse.swt.internal.carbon.smallFonts

[/sourcecode] Regards.