APEX SOAP Service

ParkLocator

public class ParkLocator {
    
        public static List<String> country(String country){
           	ParkService.ParksImplPort prkSvc = new ParkService.ParksImplPort();       
			return prkSvc.byCountry(country);
    }
    
	
}

ParkLocatorTest.asxc

@isTest
public class ParkLocatorTest {
    
    @isTest public static void countyTest(){
    	Test.setMock(WebServiceMock.class, new ParkServiceMock());    
        String country = 'United States';
        System.assertEquals(new List<String>{'Yosemite','Sequonia','Crater Lake'}, ParkLocator.country(country));
              
    }
    
	
    
}

ParkService.apxc

//Generated by wsdl2apex

public class ParkService {
    public class byCountryResponse {
        public String[] return_x;
        private String[] return_x_type_info = new String[]{'return','http://parks.services/',null,'0','-1','false'};
        private String[] apex_schema_type_info = new String[]{'http://parks.services/','false','false'};
        private String[] field_order_type_info = new String[]{'return_x'};
    }
    public class byCountry {
        public String arg0;
        private String[] arg0_type_info = new String[]{'arg0','http://parks.services/',null,'0','1','false'};
        private String[] apex_schema_type_info = new String[]{'http://parks.services/','false','false'};
        private String[] field_order_type_info = new String[]{'arg0'};
    }
    public class ParksImplPort {
        public String endpoint_x = 'https://th-apex-soap-service.herokuapp.com/service/parks';
        public Map<String,String> inputHttpHeaders_x;
        public Map<String,String> outputHttpHeaders_x;
        public String clientCertName_x;
        public String clientCert_x;
        public String clientCertPasswd_x;
        public Integer timeout_x;
        private String[] ns_map_type_info = new String[]{'http://parks.services/', 'ParkService'};
        public String[] byCountry(String arg0) {
            ParkService.byCountry request_x = new ParkService.byCountry();
            request_x.arg0 = arg0;
            ParkService.byCountryResponse response_x;
            Map<String, ParkService.byCountryResponse> response_map_x = new Map<String, ParkService.byCountryResponse>();
            response_map_x.put('response_x', response_x);
            WebServiceCallout.invoke(
              this,
              request_x,
              response_map_x,
              new String[]{endpoint_x,
              '',
              'http://parks.services/',
              'byCountry',
              'http://parks.services/',
              'byCountryResponse',
              'ParkService.byCountryResponse'}
            );
            response_x = response_map_x.get('response_x');
            return response_x.return_x;
        }
    }
}

ParkServiceMock.apxc

@isTest
global class ParkServiceMock implements WebServiceMock {
    
    global void doInvoke(
        Object stub,
        Object request,
        Map<String, Object> response,
        String endpoint,
        String soapAction,
        String requestName,
        String responseNS,
        String responseName,
        String responseType) {
            // start - specify the response you want to send
            parkService.byCountryResponse response_x = new parkService.byCountryResponse();
            response_x.return_x = new List<String>{'Yosemite','Sequonia','Crater Lake'};
            // end
            response.put('response_x', response_x); 
   }

}