JOSM Validator crashes with school holidays

[FvGordon]

What steps will reproduce the problem?

1. Add SH to opening_hours or create an object with opening_hours=SH
2. Try to upload your changes -> nothing happens (no dialog window to enter your changes - validator has crashed in background)
3. Call the validator directly -> you will get a popup window, which tells about an unexpected error. After clock on the button to report the error, you will see the text below in an extra window.

What is the expected result?

What happens instead?

Please provide any additional information below. Attach a screenshot if possible.

Happens in Version 8491 (tested) and also in latest (8658).

Revision: 8491
Repository Root: http://josm.openstreetmap.de/svn
Relative URL: ^/trunk
Last Changed Author: Don-vip
Last Changed Date: 2015-06-16 23:27:08 +0200 (Tue, 16 Jun 2015)
Build-Date: 2015-06-16 21:45:58
URL: http://josm.openstreetmap.de/svn/trunk
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last Changed Rev: 8491

Identification: JOSM/1.5 (8491 de) Windows 8.1 64-Bit
Memory Usage: 269 MB / 494 MB (145 MB allocated, but free)
Java version: 1.8.0_31, Oracle Corporation, Java HotSpot(TM) Client VM
Dataset consistency test: No problems found

Plugins:
- imageryadjust (31241)
- kendzi3d (1.0.184)
- kendzi3d-jogl (37)
- log4j (31231)
- measurement (31289)
- reverter (31241)
- turnlanes (31241)
- turnrestrictions (31241)
- undelete (31241)
- utilsplugin2 (31463)

Last errors/warnings:
- W: JCS TMS Cache - error creating URL for tile 18/138618/87273@Bing Luftbild: Attribution is not loaded yet
- W: No url returned for: 18/138618/87273@Bing Luftbild, skipping
- E: java.lang.ClassCastException: Cannot cast jdk.nashorn.internal.scripts.JO12 to jdk.nashorn.internal.scripts.JO16

java.lang.ClassCastException: Cannot cast jdk.nashorn.internal.scripts.JO12 to jdk.nashorn.internal.scripts.JO16
	at java.lang.invoke.MethodHandleImpl.newClassCastException(Unknown Source)
	at java.lang.invoke.MethodHandleImpl.castReference(Unknown Source)
	at jdk.nashorn.internal.scripts.Script$\^eval\_$5.L:3155$L:3156$parseHoliday$L:5120$L:5120(<eval>:5157)
	at jdk.nashorn.internal.scripts.Script$\^eval\_$7.L:3155$L:3156$L:6034(<eval>:6057)
	at jdk.nashorn.internal.scripts.Script$\^eval\_$7.L:3155$L:3156$L:6332$L:6333(<eval>:6338)
	at jdk.nashorn.internal.scripts.Script$\^eval\_$6.L:3155$L:3156$L:6332(<eval>:6333)
	at jdk.nashorn.internal.scripts.Script$\^eval\_$7.L:3155$L:3156$L:6457(<eval>:6458)
	at jdk.nashorn.internal.runtime.ScriptFunctionData.invoke(ScriptFunctionData.java:535)
	at jdk.nashorn.internal.runtime.ScriptFunction.invoke(ScriptFunction.java:209)
	at jdk.nashorn.internal.runtime.ScriptRuntime.apply(ScriptRuntime.java:378)
	at jdk.nashorn.api.scripting.ScriptObjectMirror.callMember(ScriptObjectMirror.java:185)
	at jdk.nashorn.api.scripting.NashornScriptEngine.invokeImpl(NashornScriptEngine.java:505)
	at jdk.nashorn.api.scripting.NashornScriptEngine.invokeMethod(NashornScriptEngine.java:236)
	at org.openstreetmap.josm.data.validation.tests.OpeningHourTest.checkOpeningHourSyntax(OpeningHourTest.java:210)
	at org.openstreetmap.josm.data.validation.tests.OpeningHourTest.checkOpeningHourSyntax(OpeningHourTest.java:181)
	at org.openstreetmap.josm.data.validation.tests.OpeningHourTest.check(OpeningHourTest.java:251)
	at org.openstreetmap.josm.data.validation.tests.OpeningHourTest.check(OpeningHourTest.java:258)
	at org.openstreetmap.josm.data.validation.Test$TagTest.visit(Test.java:118)
	at org.openstreetmap.josm.data.osm.Node.accept(Node.java:211)
	at org.openstreetmap.josm.data.validation.Test.visit(Test.java:201)
	at org.openstreetmap.josm.actions.ValidateAction$ValidationTask.realRun(ValidateAction.java:169)
	at org.openstreetmap.josm.gui.PleaseWaitRunnable.doRealRun(PleaseWaitRunnable.java:93)
	at org.openstreetmap.josm.gui.PleaseWaitRunnable.run(PleaseWaitRunnable.java:161)
	at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
	at java.util.concurrent.FutureTask.run(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
	at java.lang.Thread.run(Unknown Source)

[Don-vip]

Closed as duplicate of #10423.
This has been already fixed by Oracle, please update your version of Java.