Hanged during zoom in/out on Mac OSX

[kolen]

When zoomed in/out with mouse scroll, josm hanged. UI was redrawing but not reacting to mouse and keyboard.
Attaching thread dump (taken when was in hanged state), the following status report is from josm started again (after killing previous hanged process):

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2014-07-28 22:35:35
Last Changed Author: Don-vip
Revision: 7347
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2014-07-29 00:32:15 +0200 (Tue, 29 Jul 2014)
Last Changed Rev: 7347

Identification: JOSM/1.5 (7347 ru) Mac OS X 10.9.4
Memory Usage: 188 MB / 2731 MB (118 MB allocated, but free)
Java version: 1.7.0_67, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
VM arguments: [-Djava.security.policy=file:/Library/Internet Plug-ins/JavaAppletPlugin.plugin/Contents/Home/lib/security/javaws.policy, -DtrustProxy=true, -Xverify:remote, -Djnlpx.home=/Library/Internet Plug-ins/JavaAppletPlugin.plugin/Contents/Home/bin, -Djnlpx.origFilenameArg=/Users/kolen/Downloads/josm.jnlp, -Djnlpx.remove=true, -Dsun.awt.warmup=true, -Xbootclasspath/a:/Library/Internet Plug-ins/JavaAppletPlugin.plugin/Contents/Home/lib/javaws.jar:/Library/Internet Plug-ins/JavaAppletPlugin.plugin/Contents/Home/lib/deploy.jar:/Library/Internet Plug-ins/JavaAppletPlugin.plugin/Contents/Home/lib/plugin.jar, -Djava.util.Arrays.useLegacyMergeSort=true, -Dmacosx.jnlpx.dock.name=JOSM, -Dmacosx.jnlpx.dock.icon=/Users/kolen/Library/Application Support/Oracle/Java/Deployment/cache/6.0/34/4be781a2-72ca3a29.icns, -Djnlpx.jvm="/Library/Internet Plug-ins/JavaAppletPlugin.plugin/Contents/Home/bin/java", -Djnlpx.vmargs=LURqYXZhLnV0aWwuQXJyYXlzLnVzZUxlZ2FjeU1lcmdlU29ydD10cnVlAA==]
Dataset consistency test: No problems found

Plugin: RoadSigns (30495)
Plugin: TombPlugin (44)
Plugin: buildings_tools (30485)
Plugin: geochat (30513)
Plugin: imagery_offset_db (30534)
Plugin: log4j (30416)
Plugin: reltoolbox (30416)
Plugin: wikipedia (30449)

[Don-vip]

Some questions:

• is it reproducible with Java 8u20?
• was it in main window or in download window?
• do you have any local map style you were editing at the same time you were using JOSM?

[Don-vip]

Sounds a lot like a Java bug, especially this one: ​javabug:8047288

Please give a try to Java 8u25 or later, this problem should vanish.