package pkg

fun main(args: Array<String>) {
    println(Java.getGreeting())

                @Internal
                public Property<String> getGreeting() {
                    return greeting;
                }

                @TaskAction
                public void run() {
                    System.out.println(getGreeting().get());
                }
            }
        """

        buildFile << """

package pkg;

public class Java {
    public static String getGreeting() {
        return "Hello world!";
    }

[source,java]
----
package authoring.tutorial;

import com.gradle.CustomLib;

public class App {
    public String getGreeting() {
        return "CustomLib identifier is: " + CustomLib.identifier;
    }

    public static void main(String[] args) {
        System.out.println(new App().getGreeting());
    }
}
----

Next, let's run the task with `./gradlew :app:license`:

[source,text]
----

package org.gradle.sample;

import java.io.InputStream;
import org.apache.log4j.LogManager;

public class Greeter {
    public String getGreeting() throws Exception {
        LogManager.getRootLogger().info("Just checking if we can use external dependencies....");
        return "hello Gradle";
    }

            public class App {
                public String getGreeting() {
                    return new Producer().sayHello("Stranger");
                }

                public static void main(String[] args) {
                    System.out.println(new App().getGreeting());
                }
            }
        """

        createDirs("producer")

.App.java
[source, java]
----
package authoring.tutorial;

public class App {
    public String getGreeting() {
        return "Hello World!";
    }

    public static void main(String[] args) {
        System.out.println(new App().getGreeting());
    }
}
----

The code prints out a simple "Hello World" greeting to the screen.

The Java code in `App.java` simply prints "Hello World" to the screen:
[source,java]
----
public class App {
    public String getGreeting() {
        return "Hello World!";
    }
    public static void main(String[] args) {
        System.out.println(new App().getGreeting());
    }
}
----

[.text-right]

[source,java]
----
package authoring.tutorial;

import com.gradle.CustomLib;

public class App {
    public String getGreeting() {
        return "CustomLib identifier is: " + CustomLib.identifier;
    }

    public static void main(String[] args) {
        System.out.println(new App().getGreeting());
    }
}
----

Finally, let's run the `app` with the command `./gradlew run`:

[source]
----

            @DisableCachingByDefault(because = "test task")
            abstract class MyTask extends DefaultTask {

                @Input
                @Optional
                abstract Property<String> getGreeting();

                @Input
                Provider<String> message = greeting.map(it -> it + " from Gradle");

                @TaskAction
                void printMessage() {