"Join areas internal error" : polygon cannot merge itself at overlapping areas

[anonymous]

What steps will reproduce the problem?

1. Trying to rework the shape of a polygon of water I created an island and tried to connect by choosing to merge overlapping shapes
2. The program gave an error message

What is the expected result?

The polygon merges itself.

What happens instead?

It couldn't merge itself

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

Relative:URL: ^/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2019-07-10 00:52:47 +0200 (Wed, 10 Jul 2019)
Revision:15238
Build-Date:2019-07-10 01:30:51
URL:https://josm.openstreetmap.de/svn/trunk

Identification: JOSM/1.5 (15238 nl) Linux Mint 19.1 Tessa
Memory Usage: 1091 MB / 2800 MB (241 MB allocated, but free)
Java version: 11.0.3+7-Ubuntu-1ubuntu218.04.1, Oracle Corporation, OpenJDK 64-Bit Server VM
Screen: :0.0 1440x900
Maximum Screen Size: 1440x900
Java package: openjdk-11-jre:amd64-11.0.3+7-1ubuntu2~18.04.1
fonts-noto: fonts-noto:all-20171026-2
VM arguments: [-Djosm.restart=true, -Djava.net.useSystemProxies=true]
Dataset consistency test: No problems found

Plugins:
+ BuildingGeneralization (23)
+ ColorPlugin (1537115529)
+ CustomizePublicTransportStop (35039)
+ DxfImport (1013)
+ ImportImagePlugin (34908)
+ PicLayer (35030)
+ apache-commons (34908)
+ buildings_tools (34982)
+ ejml (35049)
+ geochat (34977)
+ geotools (34908)
+ importvec (34908)
+ indoorhelper (34977)
+ jaxb (35014)
+ jts (35064)
+ log4j (34908)
+ measurement (35051)
+ opendata (34997)
+ osm-obj-info (51)
+ utilsplugin2 (34977)

Map paint styles:
+ <josm.userdata>/styles/sit.mapcss

Last errors/warnings:
- W: No configuration settings found.  Using hardcoded default values for all pools.
- W: Kan geen ondersteunde projectie vinden voor laag AHN2 maaiveld hillshade (OSM + Private Licence !! OK)(wms). Gebruik EPSG:3857.
- W: Kan geen ondersteunde projectie vinden voor laag AHN2 maaiveld hillshade (OSM + Private Licence !! OK)(wms). Gebruik EPSG:3857.
- W: Kan geen ondersteunde projectie vinden voor laag AHN3 maaiveld hillshade (OSM + Private Licence !! OK)(wms). Gebruik EPSG:3857.
- W: Kan geen ondersteunde projectie vinden voor laag AHN3 maaiveld hillshade (OSM + Private Licence !! OK)(wms). Gebruik EPSG:3857.
- E: Handled by bug report queue: org.openstreetmap.josm.tools.JosmRuntimeException: Join areas internal error.


=== REPORTED CRASH DATA ===
BugReportExceptionHandler#handleException:
No data collected.

Warning issued by: BugReportExceptionHandler#handleException

=== STACK TRACE ===
Thread: AWT-EventQueue-0 (17) of main
org.openstreetmap.josm.tools.JosmRuntimeException: Join areas internal error.
	at org.openstreetmap.josm.actions.JoinAreasAction.findBoundaryPolygons(JoinAreasAction.java:1187)
	at org.openstreetmap.josm.actions.JoinAreasAction.joinAreas(JoinAreasAction.java:664)
	at org.openstreetmap.josm.actions.JoinAreasAction.join(JoinAreasAction.java:540)
	at org.openstreetmap.josm.actions.JoinAreasAction.actionPerformed(JoinAreasAction.java:475)
	at java.desktop/javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1967)
	at java.desktop/javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2308)
	at java.desktop/javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:405)
	at java.desktop/javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:262)
	at java.desktop/javax.swing.AbstractButton.doClick(AbstractButton.java:369)
	at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:1020)
	at java.desktop/javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:1064)
	at java.desktop/java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:297)
	at java.desktop/java.awt.Component.processMouseEvent(Component.java:6632)
	at java.desktop/javax.swing.JComponent.processMouseEvent(JComponent.java:3342)
	at java.desktop/java.awt.Component.processEvent(Component.java:6397)
	at java.desktop/java.awt.Container.processEvent(Container.java:2263)
	at java.desktop/java.awt.Component.dispatchEventImpl(Component.java:5008)
	at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2321)
	at java.desktop/java.awt.Component.dispatchEvent(Component.java:4840)
	at java.desktop/java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4918)
	at java.desktop/java.awt.LightweightDispatcher.processMouseEvent(Container.java:4547)
	at java.desktop/java.awt.LightweightDispatcher.dispatchEvent(Container.java:4488)
	at java.desktop/java.awt.Container.dispatchEventImpl(Container.java:2307)
	at java.desktop/java.awt.Window.dispatchEventImpl(Window.java:2772)
	at java.desktop/java.awt.Component.dispatchEvent(Component.java:4840)
	at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:772)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:721)
	at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:715)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:95)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:745)
	at java.desktop/java.awt.EventQueue$5.run(EventQueue.java:743)
	at java.base/java.security.AccessController.doPrivileged(Native Method)
	at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:85)
	at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:742)
	at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
	at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
	at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

[GerdP]

Closed as duplicate of #10511.