yfkwon/cli-java-prototype

Few prototypes using different API in order to use the CLI in Java

cli-java-prototype

Exemple of code related to the article CLI prototypes in Java
or in French Command Line Interface en Java

This exemple will explore how to use the Command Line Interface (CLI) in Java. We will try few API who solve the complexity of parsing the CLI:

• commoncli
• jopt-simple
• jcommando
• jcommander
• clajr
• naturalcli

How to use

The project is build with maven who make it easier to import with Eclipse.

Import project to Eclipse

First you will need to install maven on your system. Then in the console go to the project folder and run the following maven command.

cd /path/to/folder/cli-java-prototype/
mvn eclipse:eclipse

The project is now set to be import in eclipse. Open eclipse. Go to File > import...

Select Existing project into eclipse. Click Next.

CLI argument from eclipse

In order to "simulate" a your program to run from eclipse with CLI parameters, you need to create a Run or Debug Configuration.

Now hit the debug button.

Your can retrive your debug configuration in:

Compile into a jar

A executable jar need to be self-contained. It mean that all the class need to be embeded into on jar.
It's also the case with third party jar (or need to be load explicitly by reflexion)

The maven pom.xml files are using maven-assembly-plugin who make it easier to merge all those compiled .jar class into a single executable jar with the command:

mvn clean install

You can run this command at the root of the project to compile all the projects.
Or you can run this command within each sub-project to compile only this sub-project.

This command will create an executable into the "target" directory.
For the sub-project "commoncli" you will find the executable jar in /cli-java-prototype/commoncli/target/commoncli-1-jar-with-dependencies.jar

Specify the Main() of your executable jar

When creating the executable jar you need to specify where is the Main class to run.

Kind of the entry point using:

public static void main(String[] args) {
}

It also the maven-assembly-plugin who is in charge of specify this class to run from the CLI as the entry point.
Look into the pom.xml file of each project. You will find something like:

<archive>
	<manifest>
    	<addClasspath>true</addClasspath>
    	<mainClass>com.doduck.prototype.cli.jcommando.Main</mainClass>
	</manifest>
</archive>

In this case the Main class is specify to be "com.doduck.prototype.cli.jcommando.Main"

In reallity a jar file is just a zip file.
By unziping it we can notice a /META-INF/MANIFEST.MF file who contain the address of the Main class

Main-Class: com.doduck.prototype.cli.jcommando.Main

who will also find the compile .java file into .class files.

Run the jar

In the command line go to your executable jar into the /cli-java-prototype/commoncli/target/commoncli-1-jar-with-dependencies.jar directory for exemple. Then execute the following command:

java -jar commoncli-1-jar-with-dependencies.jar -myCmd -helloWorld 3

it should generate to following output in your console:

myCommand() just get call
Hello world !
Hello world !
Hello world !

Running the CLI exemples

Commoncli

Command:

java -jar commoncli-1-jar-with-dependencies.jar -myCmd -helloWorld 3

Result:

myCommand() just get call
Hello world !
Hello world !
Hello world !

Jcommando

Command:

java -jar jcommando-1-jar-with-dependencies.jar -d 3 -sendEmail -smtp smtp.mysrv.com -login myLogin -pwd myPwd

Result:

send a file by Email
smtp:smtp.mysrv.com
login:myLogin
password:myPwd

Command:

java -jar jcommando-1-jar-with-dependencies.jar -sendFtp -isSftp -host myhost.com -login myLogin -pwd mypassword -d 3

Result:

send a file by FTP
over the protocole SFTP
host:myhost.com
login:myLogin
password:mypassword

With JCommando you can create a xml file who define your command line. See /cli-java-prototype/jcommando/cli.xml
This file will generate class implementation "Cli.java" when you run the Ant command:

ant genCLI

Then you need to extend this class to overwrite the setters and the doExecute() function to process actions. See the Cli.java file.

JCommander

Command:

java -jar jcommender-1-jar-with-dependencies.jar -file /path/to/file.txt -srv ftp.mySrv.com -debug

Result:

sending file: /path/to/file.txt
to srv: ftp.mySrv.com
debug enable: true

jopt-simple

Command:

java -jar joptsimple-1-jar-with-dependencies.jar -ftp -user myUser -pass myPassword

Result:

user:myUser pass:myPassword

Command:

java -jar joptsimple-1-jar-with-dependencies.jar -f

Result:

-f exist
-f with : null

Command:

java -jar joptsimple-1-jar-with-dependencies.jar -c foo

Result:

-c exist with:foo

naturalcli

Command:

java -jar naturalcli-1-jar-with-dependencies.jar send file /home/doduck/myFile.txt to ftp://ftpsrv/dir notify theBoss with "Please, see myFile.txt on the ftp"

Result:

the file '/home/doduck/myFile.txt' was sent sucessfully
to 'ftp://ftpsrv/dir' and the user 'theBoss'
get notify with the message 'Please, see myFile.txt on the ftp'

clajr

Command:

java -jar clajr-1-jar-with-dependencies.jar -p ok -i

Result:

let's print =>ok
Here is some information

Contact

Developed by Martin Magakian
dev.martin.magakian@gmail.com
for doduck java prototype

License

MIT License (MIT)

by Anomaly Detection