Java Virtual Machine Tutorials

Hey Everyone,
Does anybody know where a good tutorial on the workings of the Java Virtual Machine can be found? I am particularly looking for information on how class loading takes place. Ideally I am looking for a tutorial that isn't to specifications orientated, something that is quite wordy and very descriptive.
If anybody can point me in the right direction I will be greatly appreciative.
Regards
David

Check this out, free online chapters of Bill Venners' Inside the Java Virtual Machine: http://www.artima.com/insidejvm/ed2/index.html Excellent book IMO.
You might also find this useful, a comparison of three JVM books: http://www.javaworld.com/jw-03-1998/jw-03-bookreview.html The one thing to note is that this comparison is rather old, and may not be entirely applicable to all the books today. Don't forget to read through the official JVM specification too, available online.
Tons of neat stuff about JVM internals can also be found at JavaWorld: http://www.javaworld.com/channel_content/jw-jvm-index.shtml

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If your library was working on your computer and then popped up empty all of a sudden then this might be what you need...
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Could not find a valid Java virtual machine to load

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tried executing the following cmd, below is the following error:
<<command i executed>>
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The crash happened outside the java virtual machine in native code

Hi,
I have a biometric device with which I am given some C++ dlls. I am trying to call methods inside these using java (jna). I am loading the dll "zkemsdk.dll+" as follows:
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Then, I am calling the function:
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This returns me true or false based on whether am connected to the biometric device or not.Thus I am able to invoke this method without issues. But for other methods inside the dll, run time exception is thrown in console:
Can someone help me resolve this issue. ??? Following is the content of the log file generated.
# A fatal error has been detected by the Java Runtime Environment:
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x0351fe3b, pid=1664, tid=3832
# JRE version: 6.0_20-b02
# Java VM: Java HotSpot(TM) Client VM (16.3-b01 mixed mode, sharing windows-x86 )
# Problematic frame:
# C [zkemsdk.dll+0xfe3b]
# If you would like to submit a bug report, please visit:
# http://www.java.net/external?url=http://java.sun.com/webapps/bugreport/crash.jsp
# The crash happened outside the Java Virtual Machine in native code.
# See problematic frame for where to report the bug.
--------------- T H R E A D ---------------
Current thread (0x003a9000): JavaThread "main" [_thread_in_native, id=3832, stack(0x008c0000,0x00910000)]
siginfo: ExceptionCode=0xc0000005, reading address 0x00000106
Registers:
EAX=0x0090f7c4, EBX=0x00000001, ECX=0x00000000, EDX=0x00000001
ESP=0x0090f7b4, EBP=0x0090f848, ESI=0x00000096, EDI=0x003a9000
EIP=0x0351fe3b, EFLAGS=0x00010216
Top of Stack: (sp=0x0090f7b4)
0x0090f7b4: 00000000 0090f930 000003fc 00000103
0x0090f7c4: 0090f800 6d9532d0 373e92a0 00912ec5
0x0090f7d4: 00000401 0090f7d8 369860d1 0090f800
0x0090f7e4: 37390050 00000000 37390f90 00000000
0x0090f7f4: 0090f800 0090f930 003a9000 0090f830
0x0090f804: 10008fd8 0090f840 0090f930 00000008
0x0090f814: 0090f88c 0090fa28 0090f8f4 0090f848
0x0090f824: eb53f637 0351ffdc 00000096 00000003
Instructions: (pc=0x0351fe3b)
0x0351fe2b: 0f 53 50 8d 44 24 18 50 e8 58 7c 00 00 83 c4 0c
0x0351fe3b: 8b 4e 70 51 8b 0e 83 c3 04 53 6a 64 8d 54 24 18
Stack: [0x008c0000,0x00910000], sp=0x0090f7b4, free space=13d0090f2e8k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C [zkemsdk.dll+0xfe3b]
C [jna5972695927945545932.tmp+0x9182]
C [jna5972695927945545932.tmp+0x2161]
C [jna5972695927945545932.tmp+0x2849]
j com.sun.jna.Function.invokeInt(I[Ljava/lang/Object;)I+0
j com.sun.jna.Function.invoke([Ljava/lang/Object;Ljava/lang/Class;)Ljava/lang/Object;+90
j com.sun.jna.Function.invoke(Ljava/lang/Class;[Ljava/lang/Object;Ljava/util/Map;)Ljava/lang/Object;+194
j com.sun.jna.Library$Handler.invoke(Ljava/lang/Object;Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;+344
j $Proxy0.Z_Beep(J)Z+19
j com.rfarrays.bhabs.fingerPrint.main([Ljava/lang/String;)V+84
v ~StubRoutines::call_stub
V [jvm.dll+0xf049c]
V [jvm.dll+0x17fcf1]
V [jvm.dll+0xf051d]
V [jvm.dll+0xf9bc5]
V [jvm.dll+0x10181d]
C [javaw.exe+0x2155]
C [javaw.exe+0x8614]
C [kernel32.dll+0xb729]
Java frames: (J=compiled Java code, j=interpreted, Vv=VM code)
j com.sun.jna.Function.invokeInt(I[Ljava/lang/Object;)I+0
j com.sun.jna.Function.invoke([Ljava/lang/Object;Ljava/lang/Class;)Ljava/lang/Object;+90
j com.sun.jna.Function.invoke(Ljava/lang/Class;[Ljava/lang/Object;Ljava/util/Map;)Ljava/lang/Object;+194
j com.sun.jna.Library$Handler.invoke(Ljava/lang/Object;Ljava/lang/reflect/Method;[Ljava/lang/Object;)Ljava/lang/Object;+344
j $Proxy0.Z_Beep(J)Z+19
j com.rfarrays.bhabs.fingerPrint.main([Ljava/lang/String;)V+84
v ~StubRoutines::call_stub
--------------- P R O C E S S ---------------
Java Threads: ( => current thread )
0x02b10c00 JavaThread "Low Memory Detector" daemon [_thread_blocked, id=1976, stack(0x02dc0000,0x02e10000)]
0x02b0a400 JavaThread "CompilerThread0" daemon [_thread_blocked, id=1280, stack(0x02d70000,0x02dc0000)]
0x02b08c00 JavaThread "Attach Listener" daemon [_thread_blocked, id=1984, stack(0x02d20000,0x02d70000)]
0x02b07800 JavaThread "Signal Dispatcher" daemon [_thread_blocked, id=2160, stack(0x02cd0000,0x02d20000)]
0x02b02400 JavaThread "Finalizer" daemon [_thread_blocked, id=2052, stack(0x02c80000,0x02cd0000)]
0x02afd800 JavaThread "Reference Handler" daemon [_thread_blocked, id=752, stack(0x02c30000,0x02c80000)]
=>0x003a9000 JavaThread "main" [_thread_in_native, id=3832, stack(0x008c0000,0x00910000)]
Other Threads:
0x02afc400 VMThread [stack: 0x02be0000,0x02c30000] [id=1504]
0x02b1b800 WatcherThread [stack: 0x02e10000,0x02e60000] [id=1980]
VM state:not at safepoint (normal execution)
VM Mutex/Monitor currently owned by a thread: None
Heap
def new generation total 4928K, used 2455K [0x22970000, 0x22ec0000, 0x27ec0000)
eden space 4416K, 55% used [0x22970000, 0x22bd5db0, 0x22dc0000)
from space 512K, 0% used [0x22dc0000, 0x22dc0000, 0x22e40000)
to space 512K, 0% used [0x22e40000, 0x22e40000, 0x22ec0000)
tenured generation total 10944K, used 0K [0x27ec0000, 0x28970000, 0x32970000)
the space 10944K, 0% used [0x27ec0000, 0x27ec0000, 0x27ec0200, 0x28970000)
compacting perm gen total 12288K, used 343K [0x32970000, 0x33570000, 0x36970000)
the space 12288K, 2% used [0x32970000, 0x329c5f20, 0x329c6000, 0x33570000)
ro space 10240K, 51% used [0x36970000, 0x36e9ae00, 0x36e9ae00, 0x37370000)
rw space 12288K, 54% used [0x37370000, 0x37a072d8, 0x37a07400, 0x37f70000)
Dynamic libraries:
0x00400000 - 0x00424000 C:\Program Files\Java\jre6\bin\javaw.exe
0x7c900000 - 0x7c9b2000 C:\WINDOWS\system32\ntdll.dll
0x7c800000 - 0x7c8f6000 C:\WINDOWS\system32\kernel32.dll
0x77dd0000 - 0x77e6b000 C:\WINDOWS\system32\ADVAPI32.dll
0x77e70000 - 0x77f03000 C:\WINDOWS\system32\RPCRT4.dll
0x77fe0000 - 0x77ff1000 C:\WINDOWS\system32\Secur32.dll
0x7e410000 - 0x7e4a1000 C:\WINDOWS\system32\USER32.dll
0x77f10000 - 0x77f59000 C:\WINDOWS\system32\GDI32.dll
0x76390000 - 0x763ad000 C:\WINDOWS\system32\IMM32.DLL
0x7c340000 - 0x7c396000 C:\Program Files\Java\jre6\bin\msvcr71.dll
0x6d800000 - 0x6da97000 C:\Program Files\Java\jre6\bin\client\jvm.dll
0x76b40000 - 0x76b6d000 C:\WINDOWS\system32\WINMM.dll
0x6d7b0000 - 0x6d7bc000 C:\Program Files\Java\jre6\bin\verify.dll
0x6d330000 - 0x6d34f000 C:\Program Files\Java\jre6\bin\java.dll
0x6d290000 - 0x6d298000 C:\Program Files\Java\jre6\bin\hpi.dll
0x76bf0000 - 0x76bfb000 C:\WINDOWS\system32\PSAPI.DLL
0x6d7f0000 - 0x6d7ff000 C:\Program Files\Java\jre6\bin\zip.dll
0x68000000 - 0x68036000 C:\WINDOWS\system32\rsaenh.dll
0x77c10000 - 0x77c68000 C:\WINDOWS\system32\msvcrt.dll
0x769c0000 - 0x76a74000 C:\WINDOWS\system32\USERENV.dll
0x5b860000 - 0x5b8b5000 C:\WINDOWS\system32\netapi32.dll
0x6d610000 - 0x6d623000 C:\Program Files\Java\jre6\bin\net.dll
0x71ab0000 - 0x71ac7000 C:\WINDOWS\system32\WS2_32.dll
0x71aa0000 - 0x71aa8000 C:\WINDOWS\system32\WS2HELP.dll
0x71a50000 - 0x71a8f000 C:\WINDOWS\System32\mswsock.dll
0x76f20000 - 0x76f47000 C:\WINDOWS\system32\DNSAPI.dll
0x76d60000 - 0x76d79000 C:\WINDOWS\system32\iphlpapi.dll
0x76fb0000 - 0x76fb8000 C:\WINDOWS\System32\winrnr.dll
0x76f60000 - 0x76f8c000 C:\WINDOWS\system32\WLDAP32.dll
0x76fc0000 - 0x76fc6000 C:\WINDOWS\system32\rasadhlp.dll
0x10000000 - 0x10052000 C:\Documents and Settings\bkonwar\Local Settings\Temp\jna5972695927945545932.tmp
0x03510000 - 0x03546000 C:\WINDOWS\system32\zkemsdk.dll
0x03560000 - 0x03574000 C:\WINDOWS\system32\commpro.dll
0x662b0000 - 0x66308000 C:\WINDOWS\system32\hnetcfg.dll
0x71a90000 - 0x71a98000 C:\WINDOWS\System32\wshtcpip.dll
VM Arguments:
jvm_args: -Dfile.encoding=Cp1252
java_command: com.xyz.bhabs.fingerPrint
Launcher Type: SUN_STANDARD
Environment Variables:
PATH=C:/Program Files/Java/jre6/bin/client;C:/Program Files/Java/jre6/bin;C:/Program Files/Java/jre6/lib/i386;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;;C:\Program Files\Java\jre1.6.0_07\bin;C:\Program Files\Android\android-sdk-windows\tools;C:\Program Files\TortoiseSVN\bin
USERNAME=BKonwar
OS=Windows_NT
PROCESSOR_IDENTIFIER=x86 Family 6 Model 15 Stepping 13, GenuineIntel
--------------- S Y S T E M ---------------
OS: Windows XP Build 2600 Service Pack 3
CPU:total 2 (2 cores per cpu, 1 threads per core) family 6 model 15 stepping 13, cmov, cx8, fxsr, mmx, sse, sse2, sse3, ssse3
Memory: 4k page, physical 2085780k(1286036k free), swap 4024188k(3249652k free)
vm_info: Java HotSpot(TM) Client VM (16.3-b01) for windows-x86 JRE (1.6.0_20-b02), built on Apr 12 2010 13:52:23 by "java_re" with MS VC++ 7.1 (VS2003)
time: Wed May 25 10:02:24 2011
elapsed time: 21 seconds
Regards,
Bhabs
Edited by: 861222 on May 25, 2011 12:19 AM

861222 wrote:
# A fatal error has been detected by the Java Runtime Environment:
# EXCEPTION_ACCESS_VIOLATION (0xc0000005) at pc=0x0351fe3b, pid=1664, tid=3832Not much to tell here. This line here looks suspiciously like a null-pointer error happening in the native code. It is impossible to say how, where and why. Go back to your code and start debugging I'd say, see where invalid data can be passed to the native code.

Could not initialize the Java Virtual Machine

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Fatal exception occured. Program will exit.
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Hello Guys!
I have a problem here and i cant find the solution!
somebody can help me?
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Copyright (C) 1999, 2005, Oracle. All rights
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"Hi,
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334758064 238778016 335544320
46294096 46294096 46399488 5.319209 >
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240036512 242217264 335544320
46317184 46317184 46399488 5.206192 >
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Rob Woollen <[email protected]> wrote:
You'd probably be better off asking this question to HP.
-- Rob
Martial wrote:
The object of this mail is the Hewlett-Packard 1.3.1.01 Hotspot JavaVirtual Machine
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http://www.hp.com/products1/unix/java/infolibrary/prog_guide/java1_3/hotspot.html#-Xverbosegc
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335544320 46118384 46118384 46137344 5.514721 >
<GC: 1 385876.530728 544 1258496 1 161087488 0 161087488 20119552 020119552 334969696
255530640 335544320 46121664 46106304 46137344 6.768760 >
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1.
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Could you please clarify this issue and/or give more information aboutgarbage
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Error occurred during initialization of VM
Could Not reserve enough space for object heap
Anyone do give me advise on how to solve this issue. Thank's alot.

What I did was:
Use
Windows Explorer to browse to C:\Users\user\AppData\Roaming\sqldeveloper\1.0.0.0.0Open
product.conf with wordpad
Go
to the bottom of the file
Uncomment
the 32 bit entry and change it to:Add32VMOption -Xmx512m

SDDM 4 EA3: Unable to launch the Java Virtual Machine (Win 7 64bit)

SQL Developer v4 EA3 is working fine, but I decided to download the stand-alone SQL Developer Data Modeler because I had seen people recommending using it in favor of the one bundled with SQLDEV.
Windows 7 64-bit
Java (64 bit) installed into C:\Program Files\Java\jdk1.7.0_25
When I double-click the short-cut to start SDDM I get the following pop-up dialog error:
Title: Oracle SQL Developer Data Modeler
Unable to launch the Java Virtual Machine
Located at path:
C:\Program Files\Java\jdk1.7.0_25\bin\msvcr100.dll
***NewsFlash***
I think I stumbled on the solution just prior to posting, so here is what worked for me in case anyone else runs into this....
I had created a desktop short-cut to "C:\Program Files\datamodeler\datamodeler.exe", which I am guessing is the 32bit version of the binary file.
I was able to launch successfully by pointing to "C:\Program Files\datamodeler\datamodeler64.exe"

That path is incorrect - strip everything after the jdk1.7.0_45\

Java Virtual Machine Tutorials

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