MVEL (MVFLEX Expression Language) Version 1.3
Fork of MVEL Version 1.3.14 which is still in user by certain projects.
Documentation can be found in the Wiki.
The more recent 2.* releases of MVEL can be found here
Download the mvel .jar file from the target directory. MVEL 1.3 is available as a single .jar file with no external dependencies.
MVEL comes with a simple shell. You can start the shell with the following command:
$ java -jar mvel-1.3.14.jar
Welcome to MVEL!The shell command help; gives some hints on how to use the shell. Shell commands must end with a ';'.
mvel$ help;
Commands
--------
echo - toggles output echo on/off
template - use the template parser shell
stacktrace - toggles stacktraces on/off
benchmark - toggles benchmark mode on/off
exectime - toggles execution time display on/off
clear - clears all variables
quit - exits the shell
The Shell allows to try out the various features of MVEL:
mvel$ 3 + 5
OUT: 8
mvel$ map = ['key':'value', 'color':'green']
OUT: {color=green, key=value}
mvel$ map.class
OUT: class java.util.HashMap
mvel$
The shell will store variables entered while the shell runs:
mvel$ x = 5
OUT: 5
mvel$ y = x + 7
OUT: 12
When you enter multiple statements on a single line the statements have to be seperated by a semi-colon. The result of the expression is the result of the last statement:
mvel$ firstName = "John"; lastName = "Doe"
OUT: Doe
You can use clear; to clear all variables stored at runtime of the shell.
mvel$ clear;
CLEARED VARIABLES.