double-cliick fails to run program.jar

[zweibieren]

On Windows 8 with a newly installed Java, double-clicking a program.jar file does not run the program. A cmd window flashes, but goes away before I can read it. There is no problem when I open a cmd window and type:

java -jar program.jar

The manifest file has got a Main-Class declaration:

Manifest-Version: 1.0
Ant-Version: Apache Ant 1.8.3
Created-By: 1.7.0_11-b21 (Oracle Corporation)
Class-Path: lib/Debug.jar lib/UI.jar lib/commons-lang3-3.1-sources.jar
  lib/commons-lang3-3.1.jar
Built-By: Zweibieren
Implementation-Vendor: physpics.com
Implementation-Title: Indexer
Implementation-Version: 3.7 (344zb Jan 22, 2013)
Main-Class: com.physpics.indexer.Indexer

Windows 8 is vastly "simplified" in file association setting. There seems to be nothing I can do.

Have you any ideas that might help???

[sehudson]

When you right click the jar, and select 'open with', do you see a Java Runtime listed? If it is, you can make it the default to open .jar files, that should work.

[zweibieren]

Thanks, I'll try this next week when I get back to the project.

Though I do wonder why a standalone JRE should differ from the JRE in the JDK that I have been using.

[jairoh_]

of the above suggestion doesn't work, try reinstalling java and it will automatically set default

[zweibieren]

Loading a jre does not help.

After many clicks to generate the flashing window. I have been able to read the error message. When I double click on U:\Fred\java\test\dist\test.jar the error is

Error: Could not find or load main class U:\Fred\java\test\dist\test.jar

This is exactly the same error I get when I give the command

java u:\Fred\java\test\dist\test.jar

It is my belief that the new file association tool is broken. It does nothing more than pass the clicked file as an argument to the associated application. That means that the crucial " -jar " is omitted from the command, as above.

The obvious answer is that java.exe should be smart enough to know the difference between a package name and a jar file.

I have had no luck attaching a .bat file as a file association.

Perhaps a C program can work.

[Norm]

Is there a command line somewhere that can be modified: insert the "-jar" option?

[zweibieren]

AHHA. The new file association scheme omits the " -jar " in trying to run the jar file.

I wrote a trivial C program to bridge th gap:

#include <string.h>
#include <stdlib.h>
void main (int argc, char **args) {
    char *jarfile = args[1];
    int n = strlen(jarfile);
    char *cmd = (char *)malloc(n+50);
    strcpy(cmd, "java -jar \'");
    strcat(cmd, jarfile);
    strcat(cmd, "\'&");
    system(cmd);
}

Compiled with "cc -o runjar.exe runjar.c" if you happen to have cygwin installed. (Attaching does not seem possible at the moment.)

To use this trick, set your file association for .jar to be runjar.exe. Then double-click on an executable jar file and it will run.

[zweibieren]

Is there a command line somewhere that can be modified: insert the "-jar" option?

Sigh. The new file association scheme for Windows 8 does away with all sorts of things, including a command line.

[Norm]

What about using the regedit program to fix the command line for .jar files?

[zweibieren]

What about using the regedit program to fix the command line for .jar files?
If you don't understand my response, don't ignore it, ask a question.

Okay, here's my question: which registry key contains the command line for .jar files?

[Norm]

Find the entry for .jar. It has the key for the entry with the command lines. On my win7 system:

The .jar entry:

[HKEY_CLASSES_ROOT\.jar]
@="jarfile_MINE"

Then the jarfile_MINE entry:

Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\jarfile_MINE]
@="Executable Jar File"

[HKEY_CLASSES_ROOT\jarfile_MINE\shell]

[HKEY_CLASSES_ROOT\jarfile_MINE\shell\Check_Referen ces]
"EditFlags"=hex:01,00,00,00
@="Check References"

[HKEY_CLASSES_ROOT\jarfile_MINE\shell\Check_Referen ces\command]
@="java.exe -cp D:\\JavaDevelopment\\runtime\\CheckClassRefs.jar;. CheckClassRefs -jar \"%1\""

[HKEY_CLASSES_ROOT\jarfile_MINE\shell\open]

[HKEY_CLASSES_ROOT\jarfile_MINE\shell\open\command]
@="\"C:\\Program Files\\Java\\jre6\\bin\\javaw.exe\" -jar \"%1\" %*"

[HKEY_CLASSES_ROOT\jarfile_MINE\shell\open_in_1.7]

[HKEY_CLASSES_ROOT\jarfile_MINE\shell\open_in_1.7\c ommand]
@="\"C:\\Program Files\\Java\\jre7_7\\bin\\java.exe\" -jar \"%1\" %*"


I use a unique name to keep installs from replacing my entry which has several right-click items.

[zweibieren]

[QUOTE=Norm;320403]Find the entry for .jar. It has the key for the entry with the command lines. On my win7 system:

[HKEY_CLASSES_ROOT\.jar]
@="jarfile_MINE"

Then the jarfile_MINE entry:
...
[HKEY_CLASSES_ROOT\jarfile_MINE\shell\open\command]
@="\"C:\\Program Files\\Java\\jre6\\bin\\javaw.exe\" -jar \"%1\" %*"

Curious. My registry has corresponding entries. No mention of runjar.exe. But for sure, runjar.exe is being run for .jar files. Sigh. My entries:

[HKEY_CLASSES_ROOT\.jar]
@="jar_auto_file"

[HKEY_CLASSES_ROOT\jar_auto_file]

[HKEY_CLASSES_ROOT\jar_auto_file\shell]

[HKEY_CLASSES_ROOT\jar_auto_file\shell\open]

[HKEY_CLASSES_ROOT\jar_auto_file\shell\open\command]
@="\"C:\\Program Files\\Java\\jdk1.7.0_11\\jre\\bin\\java.exe\" \"%1\""
NOTE MISSING "-jar"

I added the missing "-jar"
and double-click now runs .jar files. Without runjar.exe

To find how the file association is working, I searched the registry for runjar.
Its all over the place. The operative entries seem to be

[HKEY_CURRENT_USER\Software\Microsoft\Windows\Curre ntVersion\ApplicationAssociationToasts]
...
"Applications\\runjar.exe_.jar"=dword:00000000
...

[HKEY_CURRENT_USER\Software\Classes\Applications\ru njar.exe\shell\open\command]
@="\"U:\\Fred\\java\\Tools\\runjar.exe\" \"%1\""