Script Directives Reference

// Basic dependency
//DEPS info.picocli:picocli:4.6.3

// Multiple dependencies
//DEPS com.fasterxml.jackson.core:jackson-core:2.15.2
//DEPS com.fasterxml.jackson.core:jackson-databind:2.15.2

// With classifier
//DEPS io.netty:netty-transport-native-kqueue:4.1.107.Final:osx-aarch_64

// Fatjar dependency (excludes transitive dependencies)
//DEPS eu.maveniverse.maven.plugins:toolbox:0.1.9:cli@fatjar

// BOM POM for version management
//DEPS io.quarkus:quarkus-bom:3.2.0@pom
//DEPS io.quarkus:quarkus-core

// Add custom repository
//REPOS https://repo.custom.com/maven2

// Multiple repositories with names
//REPOS central,jcenter,custom=https://repo.custom.com/maven2

// Common repository shortcuts
//REPOS central,google,jitpack

// Exact version
//JAVA 17

// Minimum version
//JAVA 11+

// For preview features
//JAVA 21+
//PREVIEW

//JAVA 21+
//PREVIEW

public class RecordExample {
    // Using preview features
    record Point(int x, int y) {}

    public static void main(String[] args) {
        var p = new Point(2, 4);
        System.out.println(p);
    }
}

// Enable preview features manually
//COMPILE_OPTIONS --enable-preview -source 17

// Compiler warnings
//COMPILE_OPTIONS -Xlint:unchecked -Xlint:deprecation

// Optimization
//COMPILE_OPTIONS -O -g:none

// Memory settings
//RUNTIME_OPTIONS -Xmx2g -Xms512m

// Garbage collection
//RUNTIME_OPTIONS -XX:+UseG1GC -XX:MaxGCPauseMillis=200

// System properties
//RUNTIME_OPTIONS -Dfile.encoding=UTF-8 -Duser.timezone=UTC

// Debug settings
//RUNTIME_OPTIONS -XX:+PrintGCDetails -XX:+PrintCommandLineFlags

// Performance optimization
//RUNTIME_OPTIONS -XX:+TieredCompilation -XX:TieredStopAtLevel=1

// Basic native image optimization
//NATIVE_OPTIONS -O2 --no-fallback

// Reflection configuration
//NATIVE_OPTIONS -H:ReflectionConfigurationFiles=reflection-config.json

// Resource inclusion
//NATIVE_OPTIONS -H:IncludeResources=.*\.properties

// Advanced options
//NATIVE_OPTIONS --gc=G1 -H:+UnlockExperimentalVMOptions

// Static executable
//NATIVE_OPTIONS -H:+StaticExecutableWithDynamicLibC

//GAV com.example:my-script:1.0.0

//JAVAC_OPTIONS -parameters -Xlint:unchecked

//MAIN com.example.AlternativeMain

class Primary {
    public static void main(String[] args) {
        System.out.println("Primary main");
    }
}

class AlternativeMain {
    public static void main(String[] args) {
        System.out.println("Alternative main - this will run");
    }
}

//MODULE com.example.myapp

package com.example.myapp;

public class ModularApp {
    public static void main(String[] args) {
        System.out.println("Running as module: com.example.myapp");
    }
}

// Basic manifest entries
//MANIFEST Built-By=Developer Sealed=true

// Version information
//MANIFEST Implementation-Version=1.0.0 Implementation-Vendor=MyCompany

// Boolean flag (no value = true)
//MANIFEST Custom-Flag Multi-Release

//CDS
//RUNTIME_OPTIONS -Xms256m

class FastStartup {
    public static void main(String[] args) {
        System.out.println("Fast startup with CDS");
    }
}

// Mark as agent (for building agents)
//JAVAAGENT

// Use external agent
//JAVAAGENT io.opentelemetry.javaagent:opentelemetry-javaagent:1.20.0

// Local agent with options
//JAVAAGENT myagent.jar=option1,option2

// Remote agent
//JAVAAGENT https://repo1.maven.org/maven2/agent.jar

///usr/bin/env jbang "$0" "$@" ; exit $?
//KOTLIN 2.0.21
//DEPS org.jetbrains.kotlin:kotlin-stdlib:2.0.21

fun main(args: Array<String>) {
    println("Hello from Kotlin ${args.firstOrNull() ?: "World"}")
}

///usr/bin/env jbang "$0" "$@" ; exit $?
//GROOVY 3.0.19
//DEPS org.codehaus.groovy:groovy:3.0.19

def name = args.length > 0 ? args[0] : "World"
println "Hello from Groovy $name"

//SOURCES utils/Helper.java model/Person.java

class MainApp {
    public static void main(String[] args) {
        Helper helper = new Helper();
        Person person = new Person("Alice");
        helper.process(person);
    }
}

//FILES config.properties data.txt templates/

class FileProcessor {
    public static void main(String[] args) throws Exception {
        // These files are available in working directory
        Properties props = new Properties();
        props.load(new FileInputStream("config.properties"));

        List<String> lines = Files.readAllLines(Paths.get("data.txt"));
        System.out.println("Loaded " + lines.size() + " lines");
    }
}

//DESCRIPTION Database migration utility for MyApp
//DESCRIPTION Supports PostgreSQL and MySQL databases
//DEPS org.postgresql:postgresql:42.6.0

class DbMigrate {
    public static void main(String[] args) {
        System.out.println("Running database migration...");
    }
}

//DOCS guide=./readme.md
//DOCS guide=http://www.jbang.dev/documentation/guide/latest/index.html

jbang alias add --docs https://www.jbang.dev/documentation/guide/latest/javaversions.html itests/docsrun.java

//DOCS https://myproject.org/docs/usage.html
//DOCS docs/extra-info.md

///usr/bin/env jbang "$0" "$@" ; exit $?
//DESCRIPTION Production microservice with monitoring and metrics
//JAVA 17+
//DEPS io.quarkus:quarkus-bom:3.2.0@pom
//DEPS io.quarkus:quarkus-resteasy-reactive
//DEPS io.quarkus:quarkus-micrometer-registry-prometheus
//REPOS central,quarkus=https://repo1.maven.org/maven2/
//RUNTIME_OPTIONS -Xmx512m -XX:+UseG1GC
//NATIVE_OPTIONS --no-fallback -H:+ReportExceptionStackTraces
//MANIFEST Implementation-Version=1.0.0 Built-By=CI

// Your application code here

///usr/bin/env jbang "$0" "$@" ; exit $?
//JAVA 21+
//CDS
//RUNTIME_OPTIONS -XX:+TieredCompilation -XX:TieredStopAtLevel=1
//RUNTIME_OPTIONS -Xmx256m -XX:+UseSerialGC
//COMPILE_OPTIONS -O -g:none

// Fast-starting script

///usr/bin/env jbang "$0" "$@" ; exit $?
//SOURCES kotlin/Utils.kt groovy/Scripts.groovy
//DEPS org.jetbrains.kotlin:kotlin-stdlib:2.0.21
//DEPS org.codehaus.groovy:groovy:3.0.19
//FILES config/ templates/

// Mixed-language application

///usr/bin/env jbang "$0" "$@" ; exit $?
//DESCRIPTION Your script description
//JAVA 17+
//PREVIEW

//JAVAAGENT agent.jar
//MAIN com.example.Main
//MODULE com.example.module

//REPOS custom-repo
//DEPS dependency1
//DEPS dependency2

//SOURCES additional-files
//FILES resource-files

//MANIFEST Built-By=Developer
//COMPILE_OPTIONS -Xlint:all
//RUNTIME_OPTIONS -Xmx1g
//NATIVE_OPTIONS --no-fallback
//CDS

// Use environment variables in directives
//DEPS org.postgresql:postgresql:${env.DB_VERSION:42.6.0}
//RUNTIME_OPTIONS -Xmx${env.MAX_MEMORY:1g}

// Different options based on OS
//NATIVE_OPTIONS ${os.detected.name:linux}=-H:+StaticExecutableWithDynamicLibC
//DEPS org.openjfx:javafx-graphics:17.0.2:${os.detected.jfxname}