Error number 4001 in 4: Error while parsing velocity page /templates/xwikivars.vm Wrapped Exception: Invocation of method 'hasAccessLevel' in class com.xpn.xwiki.api.XWiki threw exception java.lang.NullPointerException @ /templates/xwikivars.vm[4,24]

Error number 4001 in 4: Error while parsing velocity page /templates/xwikivars.vm
Wrapped Exception: Invocation of method 'hasAccessLevel' in  class com.xpn.xwiki.api.XWiki threw exception java.lang.NullPointerException @ /templates/xwikivars.vm[4,24]
com.xpn.xwiki.XWikiException: Error number 4001 in 4: Error while parsing velocity page /templates/xwikivars.vm
Wrapped Exception: Invocation of method 'hasAccessLevel' in  class com.xpn.xwiki.api.XWiki threw exception java.lang.NullPointerException @ /templates/xwikivars.vm[4,24]
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:160)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1429)
	at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:598)
...
	at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:318)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1469)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1402)
	at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:598)
	at sun.reflect.GeneratedMethodAccessor147.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
	at org.apache.velocity.util.introspection.UberspectImpl$VelMethodImpl.invoke(UberspectImpl.java:295)
...
	at org.apache.velocity.runtime.parser.node.SimpleNode.render(SimpleNode.java:318)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1429)
	at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:108)
	at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:51)
	at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:263)
...
	at com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
...


Wrapped Exception:

java.lang.NullPointerException
	at com.xpn.xwiki.api.XWiki.hasAccessLevel(XWiki.java:1375)
...
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1429)
	at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:598)
...
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1469)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1402)
	at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:598)
	at sun.reflect.GeneratedMethodAccessor147.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	at java.lang.reflect.Method.invoke(Method.java:597)
...
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1429)
	at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:108)
	at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:51)
	at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:263)
...
	at com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
...


Error number 4001 in 4: Error while parsing velocity page /skins/workspaces/htmlheader.vm Wrapped Exception: Invocation of method 'parseContent' in class com.xpn.xwiki.api.XWiki threw exception java.lang.NullPointerException @ /skins/workspaces/htmlheader.vm[13,16]

Error number 4001 in 4: Error while parsing velocity page /skins/workspaces/htmlheader.vm
Wrapped Exception: Invocation of method 'parseContent' in  class com.xpn.xwiki.api.XWiki threw exception java.lang.NullPointerException @ /skins/workspaces/htmlheader.vm[13,16]
com.xpn.xwiki.XWikiException: Error number 4001 in 4: Error while parsing velocity page /skins/workspaces/htmlheader.vm
Wrapped Exception: Invocation of method 'parseContent' in  class com.xpn.xwiki.api.XWiki threw exception java.lang.NullPointerException @ /skins/workspaces/htmlheader.vm[13,16]
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:160)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1469)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1402)
	at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:598)
...
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1469)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1402)
	at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:598)
...
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1429)
	at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:108)
	at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:51)
	at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:263)
...
	at com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
...

Wrapped Exception:

java.lang.NullPointerException
	at java.util.Hashtable.put(Hashtable.java:394)
	at com.xpn.xwiki.render.DefaultXWikiRenderingEngine.renderText(DefaultXWikiRenderingEngine.java:232)
	at com.xpn.xwiki.render.DefaultXWikiRenderingEngine.interpretText(DefaultXWikiRenderingEngine.java:150)
	at com.xpn.xwiki.XWiki.parseContent(XWiki.java:1389)
	at com.xpn.xwiki.api.XWiki.parseContent(XWiki.java:545)
...
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1469)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1402)
	at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:598)
...
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1469)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1402)
	at com.xpn.xwiki.api.XWiki.parseTemplate(XWiki.java:598)
...
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:241)
	at com.xpn.xwiki.render.XWikiVelocityRenderer.evaluate(XWikiVelocityRenderer.java:155)
	at com.xpn.xwiki.XWiki.parseTemplate(XWiki.java:1429)
	at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:108)
	at com.xpn.xwiki.web.Utils.parseTemplate(Utils.java:51)
	at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:263)
...
	at com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
...

$doc.web  
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Detailed information:

        Error number 0 in 11: Uncaught exception
Wrapped Exception: String index out of range: -1
com.xpn.xwiki.XWikiException: Error number 0 in 11: Uncaught exception
Wrapped Exception: String index out of range: -1
	at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:223)
...
	at com.xpn.xwiki.web.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:117)
...


Wrapped Exception:

java.lang.StringIndexOutOfBoundsException: String index out of range: -1
	at java.lang.String.substring(String.java:1938)
	at java.lang.String.substring(String.java:1905)
	at com.xpn.xwiki.XWiki.getDocumentNameFromPath(XWiki.java:1192)
	at com.xpn.xwiki.XWiki.getDocumentName(XWiki.java:4205)
	at com.xpn.xwiki.XWiki.prepareDocuments(XWiki.java:4235)
	at com.xpn.xwiki.web.XWikiAction.execute(XWikiAction.java:173)
	...