ClassNotFoundException after canceling a plugin download

[naoliv]

I was installing RoadSigns plugin but it was taking too long to download. Then I clicked Cancel and got this:

ERRO: org.openstreetmap.josm.plugins.PluginException: Um erro ocorreu com o plugin RoadSigns. Causa: java.lang.ClassNotFoundException: org.openstreetmap.josm.plugins.roadsigns.RoadSignsPlugin
org.openstreetmap.josm.plugins.PluginException: Um erro ocorreu com o plugin RoadSigns
	at org.openstreetmap.josm.plugins.PluginInformation.loadClass(PluginInformation.java:353)
	at org.openstreetmap.josm.plugins.PluginHandler.loadPlugin(PluginHandler.java:697)
	at org.openstreetmap.josm.plugins.PluginHandler.loadPlugins(PluginHandler.java:760)
	at org.openstreetmap.josm.gui.preferences.PreferenceTabbedPane$PluginDownloadAfterTask.run(PreferenceTabbedPane.java:172)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:312)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:738)
	at java.awt.EventQueue.access$300(EventQueue.java:103)
	at java.awt.EventQueue$3.run(EventQueue.java:699)
	at java.awt.EventQueue$3.run(EventQueue.java:697)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:708)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:91)
Caused by: java.lang.ClassNotFoundException: org.openstreetmap.josm.plugins.roadsigns.RoadSignsPlugin
	at java.net.URLClassLoader$1.run(URLClassLoader.java:366)
	at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Class.java:274)
	at org.openstreetmap.josm.plugins.PluginInformation.loadClass(PluginInformation.java:351)
	... 17 more

JOSM

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2015-09-16 01:32:12
Last Changed Author: Klumbumbus
Revision: 8761
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Relative URL: ^/trunk
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2015-09-15 16:31:20 +0200 (Tue, 15 Sep 2015)
Last Changed Rev: 8761

Identification: JOSM/1.5 (8761 pt_BR) Linux Debian GNU/Linux testing (stretch)
Memory Usage: 452 MB / 9102 MB (201 MB allocated, but free)
Java version: 1.7.0_75, Oracle Corporation, OpenJDK 64-Bit Server VM
Java package: openjdk-7-jre:amd64-7u75-2.5.4-2
VM arguments: [-Dawt.useSystemAAFontSettings=on, -Dsun.java2d.opengl=true]

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