import graphql.schema.GraphQLObjectType;
import graphql.schema.GraphQLSchema;

import graphql.execution.RxExecutionStrategy;
import graphql.execution.RxExecutionResult;

import static graphql.Scalars.GraphQLString;
import static graphql.schema.GraphQLFieldDefinition.newFieldDefinition;
import static graphql.schema.GraphQLObjectType.newObject;

public class HelloWorld {

    public static void main(String[] args) {

        GraphQLObjectType queryType = newObject()
                        .name("helloWorldQuery")
                        .field(newFieldDefinition()
                                .type(GraphQLString)
                                .name("hello")
                                .staticValue(Observable.just("world")))
                                .build())
                        .build();

        GraphQLSchema schema = GraphQLSchema.newSchema()
                        .query(queryType)
                        .build();

        Observable<?> result = ((RxExecutionResult)new GraphQL(schema, new RxExecutionStrategy()).execute("{hello}")).getDataObservable();

        result.subscribe(System.out::println);
        // Prints: {hello=world}
    }
}