안녕하세요. Google 데이터 저장소에서 linkedhashset을 검색하려고하는데 아무 것도 보이지 않습니다. 한 페이지에 GWT를 사용하여 그리드에 결과를 표시하고 싶습니다. 모든 클래스에서 system.out.println()을 사용하여 잘못된 부분을 보았습니다.하지만 오류가 발생하지는 않습니다. 저는 서버 패키지 (ContactDAOJdo/ContactServiceImpl)에서 6 클래스 2를 사용하고 클라이언트 패키지 (ContactService/ContactServiceAsync/ContactListDelegate/ContactListGui)에서 4 클래스 4를 사용합니다. 왜 누군가가 이것이 효과가 없으며 올바른 방향으로 나를 가리키며 설명 할 수 있기를 바랍니다.GWT는 serviceimpl을 통해 데이터 저장소에서 목록을 검색합니다.
public class ContactDAOJdo implements ContactDAO {
@SuppressWarnings("unchecked")
@Override
public LinkedHashSet<Contact> listContacts() {
PersistenceManager pm = PmfSingleton.get().getPersistenceManager();
String query = "select from " + Contact.class.getName();
System.out.print("ContactDAOJdo: ");
return (LinkedHashSet<Contact>) pm.newQuery(query).execute();
}
}
public class ContactServiceImpl extends RemoteServiceServlet implements ContactService{
private static final long serialVersionUID = 1L;
private ContactDAO contactDAO = new ContactDAOJdo() {
@Override
public LinkedHashSet<Contact> listContacts() {
LinkedHashSet<Contact> contacts = contactDAO.listContacts();
System.out.println("service imp "+contacts);
return contacts;
}
}
@RemoteServiceRelativePath("contact")
public interface ContactService extends RemoteService {
LinkedHashSet<Contact> listContacts();
}
public interface ContactServiceAsync {
void listContacts(AsyncCallback<LinkedHashSet <Contact>> callback);
}
public class ListContactDelegate {
private ContactServiceAsync contactService = GWT.create(ContactService.class);
ListContactGUI gui;
void listContacts(){
contactService.listContacts(new AsyncCallback<LinkedHashSet<Contact>>() {
public void onFailure(Throwable caught) {
gui.service_eventListContactenFailed(caught);
System.out.println("delegate "+caught);
}
public void onSuccess(LinkedHashSet<Contact> result) {
gui.service_eventListRetrievedFromService(result);
System.out.println("delegate "+result);
}
});
}
}
public class ListContactGUI {
protected Grid contactlijst;
protected ListContactDelegate listContactService;
private Label status;
public void init() {
status = new Label();
contactlijst = new Grid();
contactlijst.setVisible(false);
status.setText("Contact list is being retrieved");
placeWidgets();
}
public void service_eventListRetrievedFromService(LinkedHashSet<Contact> result){
System.out.println("1 service eventListRetreivedFromService "+result);
status.setText("Retrieved contactlist list");
contactlijst.setVisible(true);
this.contactlijst.clear();
this.contactlijst.resizeRows(1 + result.size());
int row = 1;
this.contactlijst.setWidget(0, 0, new Label ("Voornaam"));
this.contactlijst.setWidget(0, 1, new Label ("Achternaam"));
for(Contact contact: result) {
this.contactlijst.setWidget(row, 0, new Label (contact.getVoornaam()));
this.contactlijst.setWidget(row, 1, new Label (contact.getVoornaam()));
row++;
System.out.println("voornaam: "+contact.getVoornaam());
}
System.out.println("2 service eventListRetreivedFromService "+result);
}
public void placeWidgets() {
System.out.println("placewidget inside listcontactgui" + contactlijst);
RootPanel.get("status").add(status);
RootPanel.get("contactlijst").add(contactlijst);
}
public void service_eventListContactenFailed(Throwable caught) {
status.setText("Unable to retrieve contact list from database.");
}
}