using jshell in executable UNIX scripts

Peter Levart peter.levart at
Mon Oct 10 11:03:09 UTC 2016


I don't know if this is the right list to discuss this, so please direct 
me to a more suitable place if there is one.

"jshell" command is a very nice interactive Java shell, but it could 
also be used for scripting. An executable script in any major UNIX OS is 
a textual file with executable permissions that starts with the 
following two characters: #!
The rest of the 1st line is the path to the interpreter executable and 
any arguments passed to it. The last argument passed to the interpreter 
is the path to the executable script. In case of jshell, one would want 
such script to be written like:


System.out.println("Hello World!");


The problem is that jshell tries to parse the 1st line using jshell 
syntax and the result of running above executable script is:

| Error:
|  illegal character: '#'
| #!/home/peter/Apps64/jdk9/bin/jshell
|  ^
|  Error:
|  illegal start of expression
|  #!/home/peter/Apps64/jdk9/bin/jshell
|    ^
Hello World!

The script is actually executed, but the syntax error encountered in the 
1st line is printed too.

Would it be possible for jshell to skip 1st line if it starts with 
characters #! like other shells do?

Regards, Peter

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