Multiple Spark servers in a single JVM

Question

Is there any way to run multiple instances of Sparkjava server in the same JVM? I am using it in a "plugin" software and based on external circumstances multiple instances of my plugin might be started up which then cause

java.lang.IllegalStateException: This must be done before route mapping has begun
at spark.SparkBase.throwBeforeRouteMappingException(SparkBase.java:256)
at spark.SparkBase.port(SparkBase.java:101)
at com.foo.bar.a(SourceFile:59)

It seems to me by looking at the code that it is heavily built around static fields in the code, so I am thinking about a classloader trick or working with SparkServerFactory somehow eliminating SparkBase.

Answer 1

From Spark 2.5 you can use ignite():

http://sparkjava.com/news.html#spark25released

Example:

public static void main(String[] args) {
    igniteFirstSpark();
    igniteSecondSpark();
}

static void igniteSecondSpark() {
    Service http = ignite();

    http.get("/basicHello", (q, a) -> "Hello from port 4567!");
}

static void igniteFirstSpark() {
    Service http = ignite()
                      .port(8080)
                      .threadPool(20);

    http.get("/configuredHello", (q, a) -> "Hello from port 8080!");
}

I personally initialize them something like this:

import spark.Service

public static void main(String[] args) {
    Service service1 = Service.ignite().port(8080).threadPool(20)
    Service service2 = Service.ignite().port(8081).threadPool(10)
}

I recommend to read about how to use those services outside your main method, which I think would be a great use here.