As per the JDI documentation it says for EventRequestManger.
 deleteEventRequests() "Removes a list of EventRequests."
 
 ***When list obtained from EventRequestManager.breakpointRequests()
 is passed directly to deleteEventRequests(List) the debugger VM terminates.
 But when a user defined list of the same requests is created and passed
 as an argument the requests are correctly deleted and the debugger VM
 runs to completion.
 
 But a certain unexpected behaviour has been observed in this case.

 Scenario:
 ------------
 Debugger: TestBug.java
 Debugee: EventDebugee5.java

 Three BreakpointRequests are created and events obtained.
 requestManager.deleteEventRequests(requestManager.breakpointRequests())
 does not delete all the requests and terminates the debugger VM.

 When creating a UserDefined list with the same list of breakpoint requests
 the deleteEventRequests(UserDefinedlist) deletes all the requests and
 program execution continues normally.

 Windows Testing done in (1.3-0-Z) build Hotspot and Classic.
 Solaris Testing done in (1.3.0.Z) build Hotspot and Classic..
 The output logfiles are attached for both the Windows and Solaris

Steps to reproduce the bug
 --------------------------
 The bug can be reproduced using the files in the location
 /net/sqesvr/export/disk5/toolsbugs/4331872
 Follow the instructions in README to reproduce the bug.


tim.bell@Eng 2000-10-0
New location of test is:
/net/sqesvr/export/xlt/Tools/toolsbugs/4331872

Added an ex.printStackTrace(); in the empty catch {} block.
Please don't write empty catch {} blocks.

The resulting error footprint is:

% java TestBug EventDebugee5
JVM version:1.4.0
JDI version: 1.3
JVM description: Java Debug Interface (Reference Implementation) version 1.3
Java Debug Wire Protocol (Reference Implementation) version 1.4
JVM Debug Interface version 1.0
JVM version 1.4.0 (Java HotSpot(TM) Core VM, interpreted mode)
###@###.###(java.lang.String[])+8 in thread main
In method first
###@###.###ndBreakpointMethod()+0 in thread main
In method second
###@###.###dBreakpointMethod()+0 in thread main
 first [breakpoint request EventDebugee5:20 (enabled), breakpoint request EventDebugee5:30 (enabled), breakpoint request EventDebugee5:34 (enabled)]
java.util.ConcurrentModificationException
        at java.util.AbstractList$Itr.checkForComodification(AbstractList.java:445)
        at java.util.AbstractList$Itr.next(AbstractList.java:418)
        at java.util.Collections$1.next(Collections.java:593)
        at com.sun.tools.jdi.EventRequestManagerImpl.deleteEventRequests(EventRequestManagerImpl.java:657)
        at TestBug.testRequest(TestBug.java:86)
        at TestBug.runTests(TestBug.java:51)
        at JDIScaffold.startTests(JDIScaffold.java:186)
        at TestBug.main(TestBug.java:32)