Remote debugging java web start under JVM 1.8
I have a Java Web Start application, which I used to start through a shortcut:
"C:\Program Files\Java\jdk1.7.0_67\bin\javaws.exe" -J-Dfile.encoding=UTF-8 -J-Xdebug -J-Xnoagent -J-Xrunjdwp:transport=dt_socket,server=n,suspend=y,address=8200" http://xxx/yyy/zzz.jnlp
But after installing JDK 1.8 it all stopped working, my javaws don't see any of additional X||D params. I tried this way:
setenv JAVAWS_VM_ARGS "-Dfile.encoding=UTF-8 -Xdebug -Xnoagent -Xrunjdwp:transport=dt_socket,server=n,suspend=y,address=8200"
"C:\Program Files\Java\jdk1.8.0_25\bin\javaws.exe" http://pont/dms/InstallDMS_debug.jnlp
But no use.
The only solution I found is to set params using Java control panel, adding them directly to JVM.
Control Panel > Java > Java (tab) > View (button) > Runtime parameters (field)
How can I set params for 1.8 good old way?
P.S. JDK 1.6 x32 still works well with shortcuts. x64 1.7 starts but references to 1.8 libs, so I think all JDK x64 are in collusion.
Answer
Starting from the (approximately) version 1.7.0_022 java web start launcher significantly alters list of supplied JVM-arguments and properties by treating vast of them as unsecured.
You can set the JAVA_TOOL_OPTIONS environment variable with described above debug switches instead of java control panel parameters before running JNLP file. (See http://www.oracle.com/technetwork/java/javase/envvars-138887.html#gbmsy and http://docs.oracle.com/javase/8/docs/platform/jvmti/jvmti.html#tooloptions). This is the correction of the previous Ivan' answer.
For example, you can try the following batch-file which was tested for JDK 1.8.0_60:
setlocal
set JAVAWS_TRACE_NATIVE=1
set JAVA_TOOL_OPTIONS=-agentlib:jdwp=transport=dt_socket,address=8002,server=y,suspend=n %JAVA_TOOL_OPTIONS%
set JAVA_HOME_64=c:\Java\64\jdk1.8
set JAVA_HOME=%JAVA_HOME_64%
set JDK_JRE_HOME=%JAVA_HOME%\jre
set JRE_HOME=%JDK_JRE_HOME%
set ONLINE_JNLP_URL=http://pont/dms/InstallDMS_debug.jnlp
"%JRE_HOME%\bin\javaws" %ONLINE_JNLP_URL%
endlocal
Additionally, I would like to notice that for remote debugging of Java WS-applications it is essential to run JDK's JRE but not public JRE, otherwise you can observe that JVM terminates before executing your main class.