jjs Man page

jjs Basic Tools jjs


jjs – Invokes the Nashorn engine.


jjs [options] [script-files] [– arguments]

One or more options of the jjs command, separated by spaces. For
more information, see Options.

One or more script files which you want to interpret using Nashorn,
separated by spaces. If no files are specified, an interactive
shell is started.

All values after the double hyphen marker (–) are passed through
to the script or the interactive shell as arguments. These values
can be accessed by using the arguments property (see Example 3).


The jjs command-line tool is used to invoke the Nashorn engine. You can
use it to interpret one or several script files, or to run an
interactive shell.


The options of the jjs command control the conditions under which
scripts are interpreted by Nashorn.

-cp path
-classpath path
Specifies the path to the supporting class files To set multiple
paths, the option can be repeated, or you can separate each path
with a colon (:).

Sets a system property to be passed to the script by assigning a
value to a property name. The following example shows how to invoke
Nashorn in interactive mode and assign myValue to the property
named myKey:

>> jjs -DmyKey=myValue
jjs> java.lang.System.getProperty(“myKey”)

This option can be repeated to set multiple properties.

Provides a full stack trace when an error occurs. By default, only
a brief error message is printed.

Prints the full Nashorn version string.

Launches the script as a JavaFX application.

Prints the list of options and their descriptions.

–language=[es5] Specifies the ECMAScript language version. The default version is

–optimistic-types=[true|false] Enables or disables optimistic type assumptions with deoptimizing
recompilation. Running with optimistic types will yield higher
final speed, but may increase warmup time.

Enables shell scripting features.

Enables strict mode, which enforces stronger adherence to the
standard (ECMAScript Edition 5.1), making it easier to detect
common coding errors.

Sets the specified time zone for script execution. It overrides the
time zone set in the OS and used by the Date object.

Prints the Nashorn version string.

Example 1 Running a Script with Nashorn

jjs script.js

Example 2 Running Nashorn in Interactive Mode

>> jjs
jjs> println(“Hello, World!”)
Hello, World!
jjs> quit()

Example 3 Passing Arguments to Nashorn

>> jjs — a b c
jjs> arguments.join(“, “)
a, b, c



JDK 8 03 March 2015 jjs