GSON not handlig initialized static list correctly - json

Question

If I do this:
public static volatile ArrayList<Process> processes = new ArrayList<Process>(){
{
add(new Process("News Workflow", "This is the workflow for the news segment", "image"));
}
};
and then this:
String jsonResponse = gson.toJson(processes);
jsonResponse is null.
But if I do this:
public static volatile ArrayList<Process> processes = new ArrayList<Process>();
processes.add(new Process("nam", "description", "image"));
String jsonResponse = gson.toJson(processes);
Json response is:
[{"name":"nam","description":"description","image":"image"}]
Why is that?

Answer 1

I do not know what is the problem with Gson, but do you know, that you are creating subclass of ArrayList here?
new ArrayList<Process>(){
{
add(new Process("News Workflow", "This is the workflow for the news segment", "image"));
}
};
You can check that by
System.out.println( processes.getClass().getName() );
it won't print java.util.ArrayList.
I think you wanted to use static initialization as
public static volatile ArrayList<Process> processes = new ArrayList<Process>();
static {
processes.add( new Process( "News Workflow", "This is the workflow for the news segment", "image" ) );
};
It seems that there is problem with anonymous classes, same problem is here
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
public class GSonAnonymTest {
interface Holder {
String get();
}
static Holder h = new Holder() {
String s = "value";
#Override
public String get() {
return s;
}
};
public static void main( final String[] args ) {
final GsonBuilder gb = new GsonBuilder();
final Gson gson = gb.create();
System.out.println( "h:" + gson.toJson( h ) );
System.out.println( h.get() );
}
}
UPD: look at Gson User Guide - Finer Points with Objects, last point "...anonymous classes, and local classes are ignored and not included in serialization or deserialization..."