This bug was originally marked as duplicate of bug 247651, that is already resolved. This bug is still valid, so this seems to be another bug, but it might be related.

Build: NetBeans IDE 8.0.2 (Build 201411181905)
VM: Java HotSpot(TM) 64-Bit Server VM, 24.60-b09, Java(TM) SE Runtime Environment, 1.7.0_60-b19
OS: Linux

User Comments:
GUEST: Attempting to debug, again. with it dying, again.

GUEST: java.util.concurrent.CancellationException
	at java.util.concurrent.FutureTask.report(FutureTask.java:121)
	at java.util.concurrent.FutureTask.get(FutureTask.java:202)
	at org.netbeans.modules.php.dbgp.breakpoints.LineBreakpoint.isValid(LineBreakpoint.java:151)
	at org.netbeans.modules.php.dbgp.breakpoints.LineBreakpoint.refreshValidity(LineBreakpoint.java:145)
	at org.netbeans.modules.php.dbgp.annotations.BrkpntAnnotation.<init>(BrkpntAnnotation.java:63)
	at org.netbeans.modules.php.dbgp.breakpoints.BreakpointAnnotationListener.addAnnotation(BreakpointAnnotationListener.java:105)
	at org.netbeans.modules.php.dbgp.breakpoints.BreakpointAnnotationListener.breakpointAdded(BreakpointAnnotationListener.java:82)
[catch] at org.netbeans.api.debugger.DebuggerManager.fireBreakpointCreated(DebuggerManager.java:883)
	at org.netbeans.api.debugger.DebuggerManager.addBreakpoint(DebuggerManager.java:536)
	at org.netbeans.modules.php.dbgp.breakpoints.BreakpointActionProvider.addBreakpoints(Breakpoint

GUEST: <Please provide a description of the problem or the steps to reproduce>

GUEST: opening application

GUEST: not sure what I was doing - just noticed the error

GUEST: this happening almost 5 times a day

GUEST: Toggling breakpoints

jeffreymb: Set a breakpoint. It shows up in the breakpoints list but the ui wasn't updated.

GUEST: Not sure

GUEST: Toggling breakpoint on line

herent: Not sure, honestly. It happened, then I installed some updates and restarted and it happened again while checking for external changes. The entire app has started running really slow after that.

GUEST: Tried to toggle a breakpoint in a PHP project. Based on the Breakpoints window, the breakpoint was created, but the indicator is not showing in the editor.

jeffreymb: Attempted to set a breakpoint

GUEST: a

GUEST: The error occured probably when I was removing breakpoint. Computer was under quiet a heavy laod, so Netbeans was running rather slow.

GUEST: I was just trying to debug my php page with xdebug

GUEST: This fucking IDE is really too slow

GUEST: silent exception

GUEST: sd

GUEST: running a debug project command

GUEST: nothing

GUEST: very lags and error 
when i try use breakpoint

GUEST: na

GUEST: Stopping the debugging

GUEST: endless scanning

fabriciobedoya: My Neatbeans is freezing all the time, background scanning of project take so long

GUEST: Adding a breakpoint at the same time that background scanning was in progress. After this exception - the entire IBE grinds to a crawl and requires a restart to fix it.

GUEST: debug

GUEST: <Please provide a description of the problem or the steps to reproduce>
Only clicked on the line number to set a breakpoint and the exception is done

GUEST: Trying to control click a class function in php

GUEST: try to set breakpoint




Stacktrace: 
java.util.concurrent.CancellationException
   at java.util.concurrent.FutureTask.report(FutureTask.java:0)
   at java.util.concurrent.FutureTask.get(FutureTask.java:0)
   at org.netbeans.modules.php.dbgp.breakpoints.LineBreakpoint.isValid(LineBreakpoint.java:151)
   at org.netbeans.modules.php.dbgp.breakpoints.LineBreakpoint.refreshValidity(LineBreakpoint.java:145)
   at org.netbeans.modules.php.dbgp.annotations.BrkpntAnnotation.<init>(BrkpntAnnotation.java:63)
   at org.netbeans.modules.php.dbgp.breakpoints.BreakpointAnnotationListener.addAnnotation(BreakpointAnnotationListener.java:105)