Question

I am creating a simple REST service, which owns only REST resource (java class with Jersey annotations). This REST resource needs several Java objects to work. These Java objects are very big, a few hundred MB, so it’s slow to load them into RAM. Therefore, I am trying to add these objects as static members of this REST class. However, when I send a request to the REST service, it always throws a NullPonterException. Can anyone explain why these static members are not instantiated before the REST resources(classes) are loaded? Or it’s some other reasons?

Thanks you guys in advance.

Note: those static members are just some Maps, and Lists objects, created by a class in a dependency jar.

Edit: assume the InfoConstructor below is one utility class which is responsible for creating those static objects.

code for my REST resource class is as below:

@Path("test")
public class TestResource {
    public static Map<String, Integer> vocMap = InfoConstructor.getVocMap();

    @Get
    @Produce(Media.TEXT_HTML)
    public String testGet() {
         return vocMap.hashCode();
    }
}

Answer 1

Based on the comments it sounds like the static resources are initialized correctly. More of an issue resolving class path resources. Have a look at Classpath resource within jar