Use the Clikt framework to perform command line interactions of the Java class library
Use the Clikt framework to perform command line interactions of the Java class library
Clikt is a command line interactive framework written in Kotlin. It provides a simple and elegant way to create command line tools.Through Clikt, you can build a complete command line interface by defining commands, sub -commands, parameters, and options, and use the powerful features of Clikt to process the command line parameters and options.
In order to use the CLIKT framework for the command line of the Java class library, you need to complete the following steps:
1. Add dependencies: First, you need to add the dependency item of the CLIKT framework to the project construction file.Clikt's dependencies can be obtained from the Maven Central Storage.For example, in the Maven project, you can add the following content to the pom.xml file:
<dependencies>
<dependency>
<groupId>com.github.ajalt</groupId>
<artifactId>clikt</artifactId>
<version>2.8.0</version>
</dependency>
</dependencies>
2. Create a Clikt application: Next, you need to create an application class extended from the CLIKTCOMMAND class.This class will be responsible for parsing the row parameters and options and performing the corresponding operation.The following is a simple example:
import com.github.ajalt.clikt.core.CliktCommand
import com.github.ajalt.clikt.parameters.arguments.argument
import com.github.ajalt.clikt.parameters.options.option
import com.github.ajalt.clikt.parameters.types.int
class MyApp : CliktCommand(name = "myapp", help = "A simple CLI app") {
private val numberOfPeople by option("-n", "--number", help = "Number of people").int().required()
private val message by argument(help = "Message to display")
override fun run() {
echo("Number of people: $numberOfPeople")
echo("Message: $message")
}
}
fun main(args: Array<String>) = MyApp().main(args)
In this example, we created a CliktCommand subclass called MyApp.We define an option called NumberoFPELE and a parameter called Message.The option is defined using the `Option ()` method, and the parameter uses the `argument () method to define.Then, we implemented the `Run ()" method to perform the actual application logic.In this example, we simply print out the parameters and options.
3. Run application: After completing the application of the application class, you can test it by running the application.In the command line, you can use the following command to run the application and pass the parameters and options:
$ java -jar myapp.jar --number 5 "Hello, Clikt!"
This will print a similar output:
Number of people: 5
Message: Hello, Clikt!
By reading the document of the CLIKT framework, you can learn more about the premium usage such as defining sub -commands, processing input verification, and displaying help information.In addition, Clikt also provides a flexible customized option to provide methods. By defining the `CLIKTCOMMAND` subcate's` context`, you can access the relevant final analysis options and parameters, and further process it in the following code.
In summary, the command line interaction of the Java class library using the CLIKT framework is very simple.By defining commands, sub -commands, parameters and options, and implementing corresponding logic, you can quickly build a powerful command line tool.
