JVMTI RedefineClasses will crash if class definition list includes a class representing a primitive or array type. Here is a sample err file for an array type :-

#
# An unexpected error has been detected by HotSpot Virtual Machine:
#
# Internal Error (C:\ws\service_hs_baseline\src\share\vm\runtime\handles.hpp, 236), pid=1256, tid=2020
#
# Java VM: Java HotSpot(TM) Client VM (1.5-internal-debug mixed mode)
#
# Error: assert(SharedSkipVerify || is_null() || obj->klass_part()->oop_is_instance(),"illegal type")

--------------- T H R E A D ---------------

Current thread (0x0023a228): JavaThread "main" [_thread_in_vm, id=2020]

Stack: [0x00030000,0x00070000), sp=0x0006edf4, free space=251k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
V [jvm_g.dll+0x34fc9b]
V [jvm_g.dll+0x160ce9]
V [jvm_g.dll+0xd9fbf]
V [jvm_g.dll+0x25c87d]
V [jvm_g.dll+0x25c209]
V [jvm_g.dll+0x35e0ad]
V [jvm_g.dll+0x242095]
V [jvm_g.dll+0x398d9f]
C [instrument_g.dll+0x47e2]
C [instrument_g.dll+0x1ed4]
j sun.instrument.InstrumentationImpl.redefineClasses0([Ljava/lang/instrument/ClassDefinition;)V+0
j sun.instrument.InstrumentationImpl.redefineClasses([Ljava/lang/instrument/ClassDefinition;)V+69
j Test.premain(Ljava/lang/String;Ljava/lang/instrument/Instrumentation;)V+74
v ~StubRoutines::call_stub
V [jvm_g.dll+0x1cb724]
V [jvm_g.dll+0x2ab67d]
V [jvm_g.dll+0x1cb3ef]
V [jvm_g.dll+0x2d537f]
V [jvm_g.dll+0x2d722e]
V [jvm_g.dll+0x225ba1]
C [java_g.dll+0xa7a8]
j sun.reflect.NativeMethodAccessorImpl.invoke0(Ljava/lang/reflect/Method;Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;+0
j sun.reflect.NativeMethodAccessorImpl.invoke(Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;+87
j sun.reflect.DelegatingMethodAccessorImpl.invoke(Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;+6
j java.lang.reflect.Method.invoke(Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;+111
j sun.instrument.InstrumentationImpl.loadClassAndCallPremain(Ljava/lang/String;Ljava/lang/String;)V+51
v ~StubRoutines::call_stub
V [jvm_g.dll+0x1cb724]
V [jvm_g.dll+0x2ab67d]
V [jvm_g.dll+0x1cb3ef]
V [jvm_g.dll+0x1d7c9d]
V [jvm_g.dll+0x1db88b]
C [instrument_g.dll+0x3acc]
C [instrument_g.dll+0x34fd]
C [instrument_g.dll+0x3430]
C [instrument_g.dll+0x23fc]
V [jvm_g.dll+0x24e83a]
V [jvm_g.dll+0x31cfb8]
V [jvm_g.dll+0x1edf15]
C [java_g.exe+0x2b47]
C [java_g.exe+0x12d2]
C [java_g.exe+0xabbf]
C [KERNEL32.DLL+0x11af6]

Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
j sun.instrument.InstrumentationImpl.redefineClasses0([Ljava/lang/instrument/ClassDefinition;)V+0
j sun.instrument.InstrumentationImpl.redefineClasses([Ljava/lang/instrument/ClassDefinition;)V+69
j Test.premain(Ljava/lang/String;Ljava/lang/instrument/Instrumentation;)V+74
v ~StubRoutines::call_stub
j sun.reflect.NativeMethodAccessorImpl.invoke0(Ljava/lang/reflect/Method;Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;+0
j sun.reflect.NativeMethodAccessorImpl.invoke(Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;+87
j sun.reflect.DelegatingMethodAccessorImpl.invoke(Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;+6
j java.lang.reflect.Method.invoke(Ljava/lang/Object;[Ljava/lang/Object;)Ljava/lang/Object;+111
j sun.instrument.InstrumentationImpl.loadClassAndCallPremain(Ljava/lang/String;Ljava/lang/String;)V+51
v ~StubRoutines::call_stub

--------------- P R O C E S S ---------------

Java Threads: ( => current thread )
  0x009aeda0 JavaThread "Finalizer" daemon [_thread_blocked, id=1816]
  0x009ad290 JavaThread "Reference Handler" daemon [_thread_blocked, id=1424]
=>0x0023a228 JavaThread "main" [_thread_in_vm, id=2020]

Other Threads:
  0x009a71f0 VMThread [id=932]

VM state:not at safepoint (normal execution)

VM Mutex/Monitor currently owned by a thread: None

Heap
 def new generation total 576K, used 315K [0x10270000, 0x10310000, 0x10750000)
  eden space 512K, 61% used [0x10270000, 0x102bee70, 0x102f0000)
  from space 64K, 0% used [0x102f0000, 0x102f0000, 0x10300000)
  to space 64K, 0% used [0x10300000, 0x10300000, 0x10310000)
 tenured generation total 1408K, used 0K [0x10750000, 0x108b0000, 0x14270000)
   the space 1408K, 0% used [0x10750000, 0x10750000, 0x10750200, 0x108b0000)
 compacting perm gen total 8192K, used 1396K [0x14270000, 0x14a70000, 0x18270000)
   the space 8192K, 17% used [0x14270000, 0x143cd110, 0x143cd200, 0x14a70000)
No shared spaces configured.

Dynamic libraries:
0x00400000 - 0x00411000 c:\ws\service_sdk_baseline\build\windows-i586\bin\java_g.exe
0x77f80000 - 0x77ffd000 C:\WINNT\system32\ntdll.dll
0x7c2d0000 - 0x7c332000 C:\WINNT\system32\ADVAPI32.dll
0x7c570000 - 0x7c628000 C:\WINNT\system32\KERNEL32.DLL
0x77d30000 - 0x77da1000 C:\WINNT\system32\RPCRT4.DLL
0x10200000 - 0x10264000 C:\WINNT\system32\MSVCRTD.dll
0x08000000 - 0x08632000 c:\ws\service_sdk_baseline\build\windows-i586\bin\client\jvm_g.dll
0x77e10000 - 0x77e75000 C:\WINNT\system32\USER32.dll
0x77f40000 - 0x77f7e000 C:\WINNT\system32\GDI32.DLL
0x77570000 - 0x775a0000 C:\WINNT\system32\WINMM.dll
0x10000000 - 0x1000a000 c:\ws\service_sdk_baseline\build\windows-i586\bin\hpi_g.dll
0x690a0000 - 0x690ab000 C:\WINNT\system32\PSAPI.DLL
0x00900000 - 0x00915000 c:\ws\service_sdk_baseline\build\windows-i586\bin\instrument_g.dll
0x00a30000 - 0x00a40000 c:\ws\service_sdk_baseline\build\windows-i586\bin\verify_g.dll
0x00a40000 - 0x00a64000 c:\ws\service_sdk_baseline\build\windows-i586\bin\java_g.dll
0x00a70000 - 0x00a86000 c:\ws\service_sdk_baseline\build\windows-i586\bin\zip_g.dll

VM Arguments:
jvm_args: -javaagent:Test.jar
java_command: Test

Environment Variables:
PATH=c:\ws\service_sdk_baseline\build\windows-i586\bin;C:\PROGRA~1\MKSTOO~1\bin;C:\PROGRA~1\MKSTOO~1\bin\X11;C:\PROGRA~1\MKSTOO~1\mksnt;C:\WINNT\system32;C:\WINNT;C:\WINNT\System32\Wbem
USERNAME=ab23780
SHELL=C:/PROGRA~1/MKSTOO~1/mksnt/sh.exe
DISPLAY=:0.0
OS=Windows_NT
PROCESSOR_IDENTIFIER=x86 Family 15 Model 2 Stepping 7, GenuineIntel


--------------- S Y S T E M ---------------

OS: Windows 2000 Build 2195 Service Pack 4

CPU:total 1 family 15, cmov, cx8, fxsr, mmx, sse, sse2, ht

Memory: 4k page, physical 523272k(187856k free), swap 1277784k(1086364k free)

vm_info: Java HotSpot(TM) Client VM (1.5-internal) for windows-x86, built on Jun 17 2004 09:36:27 by ab23780 with MS VC++ 6.0
###@###.### 10/7/04 00:17 GMT