Extend JNI system time implementation (incomplete)

source/ls-std/time/system-time/jni/com_lynarstudios_ls_std_time_systemtime_SystemTimeJni.cpp

@@ -3,22 +3,33 @@
 * Company:         Lynar Studios
 * E-Mail:          webmaster@lynarstudios.com
 * Created:         2023-03-16
-* Changed:         2023-04-03
+* Changed:         2023-04-04
 *
 * */
 
+#include <ls-std/core/evaluator/NullPointerEvaluator.hpp>
 #include <ls-std/time/system-time/SystemTime.hpp>
 #include <ls-std/time/system-time/jni/com_lynarstudios_ls_std_time_systemtime_SystemTimeJni.h>
+#include <memory>
 
+using ls::std::core::NullPointerEvaluator;
 using ls::std::time::DateParameter;
 using ls::std::time::SystemTime;
 using ls::std::time::type::Day;
+using std::make_shared;
+using std::shared_ptr;
 
 JNIEXPORT jboolean JNICALL Java_com_lynarstudios_ls_std_time_systemtime_SystemTimeJni_set(JNIEnv *_environment, jobject _object, jobject _dateParameter)
 {
-  jclass dateParameterClass = _environment->GetObjectClass(_dateParameter);
-  jmethodID getDayMethodId = _environment->GetMethodID(dateParameterClass, "getDay", "byte");
+  jclass dateParameterClass = _environment->FindClass("com.lynarstudios.ls.std.time.systemtime.DateParameter");
+  NullPointerEvaluator(dateParameterClass, R"lit("DateParameter" class could not be found and is null!)lit").evaluate();
+
+  jmethodID getDayMethodId = _environment->GetMethodID(dateParameterClass, "getDay", "()B");
+  NullPointerEvaluator(getDayMethodId, R"lit("getDay" method could not be found and is null!)lit").evaluate();
+
   DateParameter dateParameter{};
+  Day day = _environment->CallByteMethod((jobject) _environment, getDayMethodId, getDayMethodId);
+  dateParameter.setDay(day);
 
   return SystemTime{}.set(dateParameter);
 }