id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
18534	[Patch] Some locations cause JOSM jnlp to freeze when opening the `Imagery` menu	taylor.smock	team	"~~This ''may'' be Mac OS X only.~~ Also appears to occur on Fedora 31 (there is a pop up security warning, probably related to #18390). Same symptoms (except for the spinning pinwheel of death).

The issue appears to be on source:trunk/src/org/openstreetmap/josm/tools/ImageProvider.java#L858 -- cache remains locked by another thread indefinitely.

Is there a reason why we aren't using `java.util.concurrent.ConcurrentHashMap` instead of `java.util.HashMap`? Or an actual lock object? I know I've gotten warnings from some lint tools about using `synchronized (map)` in the past.

Alternatively, we could just wrap it in a `Collections.synchronizedMap`.

~~Please note that ''I have not'' tested it yet -- I need to figure out how to run a `jnlp` from a local source. I may end up having to spin up a server for it.~~


Steps to reproduce:
1) Start josm.jnlp (josm-latest.jnlp works as well)
2) 'http://localhost:8111/load_and_zoom?left=-47.8898656&bottom=-15.8114964&right=-47.8875375&top=-15.8092976' is the test area
3) Open `Imagery` menu"	defect	closed	normal	20.01	Core imagery	latest	fixed	jnlp, imagery