The Java 9 Module System

module A {
    requires B;
}

module B {
    exports p;
}

public static void main(String[] args) {
    List<SurpriseFactory> factories = asList(
        new ChocolateFactory(), new QuoteFactory());
    Calendar cal = Calendar.create(factories);
    println(cal.asText());
}

# compile all modules at once
$ javac -d classes
    --module-source-path "src"
    --module advent
# package one by one, eventually advent
$ jar --create
    --file mods/advent.jar
    --main-class advent.Main
    ${*.class}
# launch the application
$ java --module-path mods --module advent

public static Calendar create(
        List<SurpriseFactory> factories) {
    // ...
}

module A {
    requires transitive B;
}

module calendar {
    requires transitive surprise;
    // ...
}

module adventcalendar {
    requires transitive calendar;
    requires transitive factories;
    requires transitive surprise;
}

module factories {
    requires transitive factory.api;
    requires transitive factory.chocolate;
    requires transitive factory.quotes;
}

module calendar {
    requires transitive adventcalendar;
}

module factories {
    requires transitive adventcalendar;
}

module surprise {
    requires transitive adventcalendar;
}

module factories {
    requires transitive surprisefactories;
}

module A {
    requires static B;
}

module advent {
    requires calendar;
    requires surprise;
    requires static factory.chocolate;
    requires static factory.quote;
}

Optional<SurpriseFactory> createChocolateFactory() {
    if (isModulePresent("factory.chocolate"))
        return Optional.of(new ChocolateFactory());
    else
        return Optional.empty();
}

module uber.lib {
    requires static com.google.guava;
    requires static org.apache.commons.lang;
    requires static io.vavr;
    requires static com.aol.cyclops;
}

// consumer
module A {
    uses some.Service;
}

// provider
module B {
    provides some.Service
        with some.Type;
}

ServiceLoader.load(Service.class)

module advent {
    requires surprise;
    uses surprise.SurpriseFactory;
}

module factory.chocolate {
    requires surprise;
    provides surprise.SurpriseFactory
        with factory.quote.ChocolateFactory;
}

module factory.quote {
    requires surprise;
    provides surprise.SurpriseFactory
        with factory.quote.QuoteFactory;
}

public static void main(String[] args) {
    List<SurpriseFactory> factories = ServiceLoader
        .load(SurpriseFactory.class).stream()
        .map(Provider::get)
        .collect(toList());
    Calendar cal = Calendar.create(factories);
    System.out.println(cal.asText());
}

module A {
    exports some.pack to B;
}

module factory {
    requires transitive surprise;
    exports factory
        to factory.chocolate, factory.quote;
}

module A {
    opens some.pack;
}

open module A {
    // no more `opens` directives
}

$ jdeps sh-2.6.3.jar

> sh-2.6.3.jar -> java.base
> sh-2.6.3.jar -> java.datatransfer
> sh-2.6.3.jar -> java.desktop
# ... truncated more module dependencies ...
>    edu.udo.sh -> com.beust.jcommander  not found
>    edu.udo.sh -> edu.udo.sh.data       sh-2.6.3.jar
>    edu.udo.sh -> edu.udo.sh.gui        sh-2.6.3.jar
>    edu.udo.sh -> edu.udo.sh.gui.util   sh-2.6.3.jar
>    edu.udo.sh -> edu.udo.sh.util       sh-2.6.3.jar
>    edu.udo.sh -> java.io               java.base
>    edu.udo.sh -> java.lang             java.base
>    edu.udo.sh -> javax.swing           java.desktop
# ... truncated many more package dependencies ...

$ jdeps
    --class-path 'libs/*' -recursive
    sh-2.6.3.jar

# ... truncated split package warnings ...
# ... truncated some module/JAR dependencies...
> sh-2.6.3.jar -> libs/commons-codec-1.6.jar
> sh-2.6.3.jar -> libs/commons-io-2.4.jar
> sh-2.6.3.jar -> libs/dom4j-1.6.1.jar
> sh-2.6.3.jar -> libs/exp4j-0.1.38.jar
> sh-2.6.3.jar -> libs/guava-18.0.jar
# ... truncated more module/JAR dependencies...
# ... truncated many, many package dependencies ...

$ jdeps
    --class-path 'libs/*' -recursive
    --dot-output dots
    sh-2.6.3.jar
# sed -i 's/-1.0-SNAPSHOT.jar//g' summary.dot
# sed -i '/java.base/d' summary.dot
$ dot -Tpng -O dots/summary.dot

$ jdeps
    --class-path 'libs/*' -recursive
    --jdk-internals
    sh-2.6.3.jar

$ jlink
#   define output folder for the image
    --output jdk
#   where to find modules?
    --module-path $JAVA_HOME/jmods
#   which modules to add (includes dependencies!)
    --add-modules java.base

$ jdk/bin/java --list-modules
> java.base

$ jlink
    --output jdk
    --module-path $JAVA_HOME/jmods
    --add-modules java.xml.ws,java.xml,java.xml.bind
    --add-modules java.sql,java.logging

$ jdk/bin/java --list-modules
> java.activation
> java.base
> java.compiler
> java.datatransfer
> java.desktop
> java.logging
> java.management
> java.prefs
> java.sql
> java.xml
> java.xml.bind
> java.xml.ws
> java.xml.ws.annotation
> jdk.httpserver
> jdk.unsupported

$ jlink
    --output jdk
    --module-path $JAVA_HOME/jmods:mods
    --add-modules advent
#   services are not resolves automatically
    --add-modules factory.surprise,factory.chocolate

jdk/bin/java --module advent

$ jlink
    --output jdk
    --module-path $JAVA_HOME/jmods:mods
    --add-modules advent,...
#   --launcher <name>=<module>[/<mainclass>]
    --launcher calendar=advent

jdk/bin/calendar