Getting Started with Æsh

This guide will help you get started with Æsh quickly.

Installation

Add the following dependency to your Maven project:

<dependency>
  <groupId>org.aesh</groupId>
  <artifactId>aesh</artifactId>
  <version>1.7</version>
</dependency>

For Gradle:

dependencies {
    implementation group: 'org.aesh', name: 'aesh', version: '1.7'
}

Your First Command

The simplest way to create a command is to annotate a class that implements the Command interface:

import org.aesh.command.Command;
import org.aesh.command.CommandDefinition;
import org.aesh.command.CommandResult;
import org.aesh.command.invocation.CommandInvocation;

@CommandDefinition(name = "hello", description = "Print a greeting")
public class HelloCommand implements Command<CommandInvocation> {

    @Override
    public CommandResult execute(CommandInvocation invocation) {
        invocation.println("Hello from Æsh!");
        return CommandResult.SUCCESS;
    }
}

Running your first Command

Use the AeshConsoleRunner to start an interactive console:

import org.aesh.AeshConsoleRunner;

public class Main {
    public static void main(String[] args) {
        AeshConsoleRunner.builder()
                .command(HelloCommand.class)
                .prompt("[myshell]$ ")
                .addExitCommand()
                .start();
    }
}

Adding Options

Add options to your command using the @Option annotation:

@CommandDefinition(name = "greet", description = "Greet someone")
public class GreetCommand implements Command<CommandInvocation> {

    @Option(shortName = 'n', description = "Name to greet")
    private String name = "World";

    @Override
    public CommandResult execute(CommandInvocation invocation) {
        invocation.println("Hello, " + name + "!");
        return CommandResult.SUCCESS;
    }
}

Now users can run greet (defaults to “World”) or greet --name Alice / greet -n Alice.

Multiple Commands

AeshConsoleRunner.builder()
        .command(HelloCommand.class)
        .command(GreetCommand.class)
        .prompt("[myshell]$ ")
        .addExitCommand()
        .start();

Next Steps

Now that you understand the basics:

Learn about Command Definitions to create more complex commands
Explore Options and Arguments for powerful command-line interfaces
Check out the Console and Runtime Runners for different execution modes
Browse complete working code in Examples and Tutorials

Working Examples

The aesh-examples repository contains several getting-started examples:

getting-started - Complete CLI example with multiple commands
getting-started-input - Examples showing how to handle different types of input
getting-started-runtime - Single command execution for CLI tools

See the Examples and Tutorials page for detailed information about all available examples.

Installation Command Definition