JSF-Datamodel&JPA父级用于离开导航。如何？
我的web应用程序是一个基于JSF2.0/JPA的CRUD web应用程序，使用JavaEE5和JDK1.6。在Glassfish 3.1上运行。IDE是Netbeans 7.0。我不使用EJB，也不使用CDI 问题 我现在可以实现的是在我的实体上执行CRUD。这很好。对于我拥有的每个实体： 列出datatable中该实体的所有Datamodel项的List.xhtml Create.xhtml创建新项的表单 View.xhtml用于查看项目的表单 Edit.xhtml用于编辑项目的表单 结构 实体包：实体。 控制器包：jpa控制器Javax持久性。。。 jsf包：每个实体会话作用域的托管bean。 但主要问题是父叶导航。我希望我的webapp与netbeans7.0附带的演示应用程序agilescrumtoys做同样的事情。或SpringFuse的演示webapp，否则： 例如：当你在一个列表中显示一个作者列表时，你有最后一个放置三个作者的位置，用于编辑、查看和删除所选行。 我想做的是在同一列中添加另一个，使我能够查看与所选行相关的子对象集合。 因此，我想显示一个特定作家所写的书的列表 作者1------*书一对多关系 当用户单击 它将其转发到/book/List.xhtml，此时将显示所选WRITEr行的列表。依此类推，从图书数据表中，从给定的行中，我单击以获取给定图书的参考文献列表。 @Matt给出的提示是使用《托管bean》一书中的一个方法：JSF-Datamodel&JPA父级用于离开导航。如何？,jsf,jpa,netbeans,crud,java-ee-5,Jsf,Jpa,Netbeans,Crud,Java Ee 5,我的web应用程序是一个基于JSF2.0/JPA的CRUD web应用程序，使用JavaEE5和JDK1.6。在Glassfish 3.1上运行。IDE是Netbeans 7.0。我不使用EJB，也不使用CDI 问题 我现在可以实现的是在我的实体上执行CRUD。这很好。对于我拥有的每个实体： 列出datatable中该实体的所有Datamodel项的List.xhtml Create.xhtml创建新项的表单 View.xhtml用于查看项目的表单 Edit.xhtml用于编辑项目的表单 结构
public showBooksForWriter(Writer writer) {
// TODO: get the selected writer
// Get the list of books for the selected writer
return "/book/List"; // Outcome
}
<h:datatable value="#{writerController.items}" var="w">
.....
<h:column>
<h:commandButton action="#{bookController.showBooksForWriter(w}" value="Show Books For Writer"/>
</h:column>
....
</h:datatable>
@ManagedBean(name = "writerController")
@SessionScoped
public class WriterController implements Serializable {
@Resource
private UserTransaction utx = null;
@PersistenceUnit(unitName = "writerPU")
private EntityManagerFactory emf = null;
private Writer current;
private DataModel items = null;
private WriterJpaController jpaController = null;
private PaginationHelper pagination;
private int selectedItemIndex;
public WriterController() {
}
public Writer getSelected() {
if (current == null) {
current = new Writer();
selectedItemIndex = -1;
}
return current;
}
private WriterJpaController getJpaController() {
if (jpaController == null) {
jpaController = new WriterJpaController(utx, emf);
}
return jpaController;
}
public PaginationHelper getPagination() {
if (pagination == null) {
pagination = new PaginationHelper(10) {
@Override
public int getItemsCount() {
return getJpaController().getWriterCount();
}
@Override
public DataModel createPageDataModel() {
return new ListDataModel(getJpaController().findWriterEntities(getPageSize(), getPageFirstItem()));
}
};
}
return pagination;
}
public String prepareList() {
recreateModel();
return "List";
}
public String prepareView() {
current = (Writer) getItems().getRowData();
selectedItemIndex = pagination.getPageFirstItem() + getItems().getRowIndex();
return "View";
}
public String prepareCreate() {
current = new Writer();
selectedItemIndex = -1;
return "Create";
}
public String create() {
try {
getJpaController().create(current);
JsfUtil.addSuccessMessage(ResourceBundle.getBundle("/Bundle").getString("WriterCreated"));
return prepareCreate();
} catch (Exception e) {
JsfUtil.addErrorMessage(e, ResourceBundle.getBundle("/Bundle").getString("PersistenceErrorOccured"));
return null;
}
}
public String prepareEdit() {
current = (Writer) getItems().getRowData();
selectedItemIndex = pagination.getPageFirstItem() + getItems().getRowIndex();
return "Edit";
}
public String update() {
try {
getJpaController().edit(current);
JsfUtil.addSuccessMessage(ResourceBundle.getBundle("/Bundle").getString("WriterUpdated"));
return "View";
} catch (Exception e) {
JsfUtil.addErrorMessage(e, ResourceBundle.getBundle("/Bundle").getString("PersistenceErrorOccured"));
return null;
}
}
public String destroy() {
current = (Writer) getItems().getRowData();
selectedItemIndex = pagination.getPageFirstItem() + getItems().getRowIndex();
performDestroy();
recreateModel();
return "List";
}
public String destroyAndView() {
performDestroy();
recreateModel();
updateCurrentItem();
if (selectedItemIndex >= 0) {
return "View";
} else {
// all items were removed - go back to list
recreateModel();
return "List";
}
}
private void performDestroy() {
try {
getJpaController().destroy(current.getWriterid());
JsfUtil.addSuccessMessage(ResourceBundle.getBundle("/Bundle").getString("WriterDeleted"));
} catch (Exception e) {
JsfUtil.addErrorMessage(e, ResourceBundle.getBundle("/Bundle").getString("PersistenceErrorOccured"));
}
}
private void updateCurrentItem() {
int count = getJpaController().getWriterCount();
if (selectedItemIndex >= count) {
// selected index cannot be bigger than number of items:
selectedItemIndex = count - 1;
// go to previous page if last page disappeared:
if (pagination.getPageFirstItem() >= count) {
pagination.previousPage();
}
}
if (selectedItemIndex >= 0) {
current = getJpaController().findWriterEntities(1, selectedItemIndex).get(0);
}
}
public DataModel getItems() {
if (items == null) {
items = getPagination().createPageDataModel();
}
return items;
}
private void recreateModel() {
items = null;
}
public String next() {
getPagination().nextPage();
recreateModel();
return "List";
}
public String previous() {
getPagination().previousPage();
recreateModel();
return "List";
}
public SelectItem[] getItemsAvailableSelectMany() {
return JsfUtil.getSelectItems(getJpaController().findWriterEntities(), false);
}
public SelectItem[] getItemsAvailableSelectOne() {
return JsfUtil.getSelectItems(getJpaController().findWriterEntities(), true);
}
@FacesConverter(forClass = Writer.class)
public static class WriterControllerConverter implements Converter {
public Object getAsObject(FacesContext facesContext, UIComponent component, String value) {
if (value == null || value.length() == 0) {
return null;
}
WriterController controller = (WriterController) facesContext.getApplication().getELResolver().
getValue(facesContext.getELContext(), null, "writerController");
return controller.getJpaController().findWriter(getKey(value));
}
java.lang.Integer getKey(String value) {
java.lang.Integer key;
key = Integer.valueOf(value);
return key;
}
String getStringKey(java.lang.Integer value) {
StringBuffer sb = new StringBuffer();
sb.append(value);
return sb.toString();
}
public String getAsString(FacesContext facesContext, UIComponent component, Object object) {
if (object == null) {
return null;
}
if (object instanceof Writer) {
Writer o = (Writer) object;
return getStringKey(o.getWriterid());
} else {
throw new IllegalArgumentException("object " + object + " is of type " + object.getClass().getName() + "; expected type: " + WriterController.class.getName());
}
}
}
}
public class JsfUtil {
public static SelectItem[] getSelectItems(List<?> entities, boolean selectOne) {
int size = selectOne ? entities.size() + 1 : entities.size();
SelectItem[] items = new SelectItem[size];
int i = 0;
if (selectOne) {
items[0] = new SelectItem("", "---");
i++;
}
for (Object x : entities) {
items[i++] = new SelectItem(x, x.toString());
}
return items;
}
public static void addErrorMessage(Exception ex, String defaultMsg) {
String msg = ex.getLocalizedMessage();
if (msg != null && msg.length() > 0) {
addErrorMessage(msg);
} else {
addErrorMessage(defaultMsg);
}
}
public static void addErrorMessages(List<String> messages) {
for (String message : messages) {
addErrorMessage(message);
}
}
public static void addErrorMessage(String msg) {
FacesMessage facesMsg = new FacesMessage(FacesMessage.SEVERITY_ERROR, msg, msg);
FacesContext.getCurrentInstance().addMessage(null, facesMsg);
}
public static void addSuccessMessage(String msg) {
FacesMessage facesMsg = new FacesMessage(FacesMessage.SEVERITY_INFO, msg, msg);
FacesContext.getCurrentInstance().addMessage("successInfo", facesMsg);
}
public static String getRequestParameter(String key) {
return FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap().get(key);
}
public static Object getObjectFromRequestParameter(String requestParameterName, Converter converter, UIComponent component) {
String theId = JsfUtil.getRequestParameter(requestParameterName);
return converter.getAsObject(FacesContext.getCurrentInstance(), component, theId);
}
}
@ManagedBean(name = "writerController")
@SessionScoped
public class WriterController implements Serializable {
@Resource
private UserTransaction utx = null;
@PersistenceUnit(unitName = "writerPU")
private EntityManagerFactory emf = null;
private Writer current;
private DataModel items = null;
private WriterJpaController jpaController = null;
private PaginationHelper pagination;
private int selectedItemIndex;
public WriterController() {
}
public Writer getSelected() {
if (current == null) {
current = new Writer();
selectedItemIndex = -1;
}
return current;
}
private WriterJpaController getJpaController() {
if (jpaController == null) {
jpaController = new WriterJpaController(utx, emf);
}
return jpaController;
}
public PaginationHelper getPagination() {
if (pagination == null) {
pagination = new PaginationHelper(10) {
@Override
public int getItemsCount() {
return getJpaController().getWriterCount();
}
@Override
public DataModel createPageDataModel() {
return new ListDataModel(getJpaController().findWriterEntities(getPageSize(), getPageFirstItem()));
}
};
}
return pagination;
}
public String prepareList() {
recreateModel();
return "List";
}
public String prepareView() {
current = (Writer) getItems().getRowData();
selectedItemIndex = pagination.getPageFirstItem() + getItems().getRowIndex();
return "View";
}
public String prepareCreate() {
current = new Writer();
selectedItemIndex = -1;
return "Create";
}
public String create() {
try {
getJpaController().create(current);
JsfUtil.addSuccessMessage(ResourceBundle.getBundle("/Bundle").getString("WriterCreated"));
return prepareCreate();
} catch (Exception e) {
JsfUtil.addErrorMessage(e, ResourceBundle.getBundle("/Bundle").getString("PersistenceErrorOccured"));
return null;
}
}
public String prepareEdit() {
current = (Writer) getItems().getRowData();
selectedItemIndex = pagination.getPageFirstItem() + getItems().getRowIndex();
return "Edit";
}
public String update() {
try {
getJpaController().edit(current);
JsfUtil.addSuccessMessage(ResourceBundle.getBundle("/Bundle").getString("WriterUpdated"));
return "View";
} catch (Exception e) {
JsfUtil.addErrorMessage(e, ResourceBundle.getBundle("/Bundle").getString("PersistenceErrorOccured"));
return null;
}
}
public String destroy() {
current = (Writer) getItems().getRowData();
selectedItemIndex = pagination.getPageFirstItem() + getItems().getRowIndex();
performDestroy();
recreateModel();
return "List";
}
public String destroyAndView() {
performDestroy();
recreateModel();
updateCurrentItem();
if (selectedItemIndex >= 0) {
return "View";
} else {
// all items were removed - go back to list
recreateModel();
return "List";
}
}
private void performDestroy() {
try {
getJpaController().destroy(current.getWriterid());
JsfUtil.addSuccessMessage(ResourceBundle.getBundle("/Bundle").getString("WriterDeleted"));
} catch (Exception e) {
JsfUtil.addErrorMessage(e, ResourceBundle.getBundle("/Bundle").getString("PersistenceErrorOccured"));
}
}
private void updateCurrentItem() {
int count = getJpaController().getWriterCount();
if (selectedItemIndex >= count) {
// selected index cannot be bigger than number of items:
selectedItemIndex = count - 1;
// go to previous page if last page disappeared:
if (pagination.getPageFirstItem() >= count) {
pagination.previousPage();
}
}
if (selectedItemIndex >= 0) {
current = getJpaController().findWriterEntities(1, selectedItemIndex).get(0);
}
}
public DataModel getItems() {
if (items == null) {
items = getPagination().createPageDataModel();
}
return items;
}
private void recreateModel() {
items = null;
}
public String next() {
getPagination().nextPage();
recreateModel();
return "List";
}
public String previous() {
getPagination().previousPage();
recreateModel();
return "List";
}
public SelectItem[] getItemsAvailableSelectMany() {
return JsfUtil.getSelectItems(getJpaController().findWriterEntities(), false);
}
public SelectItem[] getItemsAvailableSelectOne() {
return JsfUtil.getSelectItems(getJpaController().findWriterEntities(), true);
}
@FacesConverter(forClass = Writer.class)
public static class WriterControllerConverter implements Converter {
public Object getAsObject(FacesContext facesContext, UIComponent component, String value) {
if (value == null || value.length() == 0) {
return null;
}
WriterController controller = (WriterController) facesContext.getApplication().getELResolver().
getValue(facesContext.getELContext(), null, "writerController");
return controller.getJpaController().findWriter(getKey(value));
}
java.lang.Integer getKey(String value) {
java.lang.Integer key;
key = Integer.valueOf(value);
return key;
}
String getStringKey(java.lang.Integer value) {
StringBuffer sb = new StringBuffer();
sb.append(value);
return sb.toString();
}
public String getAsString(FacesContext facesContext, UIComponent component, Object object) {
if (object == null) {
return null;
}
if (object instanceof Writer) {
Writer o = (Writer) object;
return getStringKey(o.getWriterid());
} else {
throw new IllegalArgumentException("object " + object + " is of type " + object.getClass().getName() + "; expected type: " + WriterController.class.getName());
}
}
}
}
public class JsfUtil {
public static SelectItem[] getSelectItems(List<?> entities, boolean selectOne) {
int size = selectOne ? entities.size() + 1 : entities.size();
SelectItem[] items = new SelectItem[size];
int i = 0;
if (selectOne) {
items[0] = new SelectItem("", "---");
i++;
}
for (Object x : entities) {
items[i++] = new SelectItem(x, x.toString());
}
return items;
}
public static void addErrorMessage(Exception ex, String defaultMsg) {
String msg = ex.getLocalizedMessage();
if (msg != null && msg.length() > 0) {
addErrorMessage(msg);
} else {
addErrorMessage(defaultMsg);
}
}
public static void addErrorMessages(List<String> messages) {
for (String message : messages) {
addErrorMessage(message);
}
}
public static void addErrorMessage(String msg) {
FacesMessage facesMsg = new FacesMessage(FacesMessage.SEVERITY_ERROR, msg, msg);
FacesContext.getCurrentInstance().addMessage(null, facesMsg);
}
public static void addSuccessMessage(String msg) {
FacesMessage facesMsg = new FacesMessage(FacesMessage.SEVERITY_INFO, msg, msg);
FacesContext.getCurrentInstance().addMessage("successInfo", facesMsg);
}
public static String getRequestParameter(String key) {
return FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap().get(key);
}
public static Object getObjectFromRequestParameter(String requestParameterName, Converter converter, UIComponent component) {
String theId = JsfUtil.getRequestParameter(requestParameterName);
return converter.getAsObject(FacesContext.getCurrentInstance(), component, theId);
}
}
package jsf.util;
import javax.faces.model.DataModel;
public abstract class PaginationHelper {
private int pageSize;
private int page;
public PaginationHelper(int pageSize) {
this.pageSize = pageSize;
}
public abstract int getItemsCount();
public abstract DataModel createPageDataModel();
public int getPageFirstItem() {
return page * pageSize;
}
public int getPageLastItem() {
int i = getPageFirstItem() + pageSize - 1;
int count = getItemsCount() - 1;
if (i > count) {
i = count;
}
if (i < 0) {
i = 0;
}
return i;
}
public boolean isHasNextPage() {
return (page + 1) * pageSize + 1 <= getItemsCount();
}
public void nextPage() {
if (isHasNextPage()) {
page++;
}
}
public boolean isHasPreviousPage() {
return page > 0;
}
public void previousPage() {
if (isHasPreviousPage()) {
page--;
}
}
public int getPageSize() {
return pageSize;
}
} // END of CLASS
当然，您真的在使用JavaEE5吗？换句话说，您的web.xml是根据Servlet2.5规范声明的吗？这意味着EL 2.1，在此EL版本中不支持在EL中传递方法参数。Glassfish 3.1是一个Java EE 6容器，它支持Servlet 3.0，并且隐式支持EL 2.2，其中支持在EL中传递方法参数。如果将web.xml重新声明为Servlet 3.0，那么应该能够在EL中传递方法参数。这样您就不一定需要数据模型了。@BalusC对不起！我不知道你的评论。天哪！！实际上是2.5@BalusC I被命令使用JSF数据模型，这就是我哭泣的原因：我已经使用了一个方法：{ddnController.setPatientitem.id}，该方法在数据表中运行良好。我一直认为我从一开始就在使用EL2.2，因为我的web中使用的默认库是与Glassfish 3.1捆绑在一起的库，并且在使用诸如：{myproperty.size}或{empty bean.att或bean.toto.equalssoso}等新特性时没有问题
package jsf.util;
import javax.faces.model.DataModel;
public abstract class PaginationHelper {
private int pageSize;
private int page;
public PaginationHelper(int pageSize) {
this.pageSize = pageSize;
}
public abstract int getItemsCount();
public abstract DataModel createPageDataModel();
public int getPageFirstItem() {
return page * pageSize;
}
public int getPageLastItem() {
int i = getPageFirstItem() + pageSize - 1;
int count = getItemsCount() - 1;
if (i > count) {
i = count;
}
if (i < 0) {
i = 0;
}
return i;
}
public boolean isHasNextPage() {
return (page + 1) * pageSize + 1 <= getItemsCount();
}
public void nextPage() {
if (isHasNextPage()) {
page++;
}
}
public boolean isHasPreviousPage() {
return page > 0;
}
public void previousPage() {
if (isHasPreviousPage()) {
page--;
}
}
public int getPageSize() {
return pageSize;
}
} // END of CLASS
package jpa.controllers;
import entities.Writer;
// other imports here
public class WriterJpaController implements Serializable {
public WriterJpaController(UserTransaction utx, EntityManagerFactory emf) {
this.utx = utx;
this.emf = emf;
}
private UserTransaction utx = null;
private EntityManagerFactory emf = null;
public EntityManager getEntityManager() {
return emf.createEntityManager();
}
public void create(Writer writer) throws RollbackFailureException, Exception {
if (writer.getTopicList() == null) {
writer.setTopicList(new ArrayList<Topic>());
}
if (writer.getEvaluationList() == null) {
writer.setEvaluationList(new ArrayList<Evaluation>());
}
if (writer.getBookList() == null) {
writer.setBookList(new ArrayList<Book>());
}
EntityManager em = null;
try {
utx.begin();
em = getEntityManager();
List<Topic> attachedTopicList = new ArrayList<Topic>();
for (Topic topicListTopicToAttach : writer.getTopicList()) {
topicListTopicToAttach = em.getReference(topicListTopicToAttach.getClass(), topicListTopicToAttach.getTopicname());
attachedTopicList.add(topicListTopicToAttach);
}
writer.setTopicList(attachedTopicList);
List<Evaluation> attachedEvaluationList = new ArrayList<Evaluation>();
for (Evaluation evaluationListEvaluationToAttach : writer.getEvaluationList()) {
evaluationListEvaluationToAttach = em.getReference(evaluationListEvaluationToAttach.getClass(), evaluationListEvaluationToAttach.getEvaluationPK());
attachedEvaluationList.add(evaluationListEvaluationToAttach);
}
writer.setEvaluationList(attachedEvaluationList);
List<Book> attachedBookList = new ArrayList<Book>();
for (Book bookListBookToAttach : writer.getBookList()) {
bookListBookToAttach = em.getReference(bookListBookToAttach.getClass(), bookListBookToAttach.getBookPK());
attachedBookList.add(bookListBookToAttach);
}
writer.setBookList(attachedBookList);
em.persist(writer);
for (Topic topicListTopic : writer.getTopicList()) {
topicListTopic.getWriterList().add(writer);
topicListTopic = em.merge(topicListTopic);
}
for (Evaluation evaluationListEvaluation : writer.getEvaluationList()) {
Writer oldWriterOfEvaluationListEvaluation = evaluationListEvaluation.getWriter();
evaluationListEvaluation.setWriter(writer);
evaluationListEvaluation = em.merge(evaluationListEvaluation);
if (oldWriterOfEvaluationListEvaluation != null) {
oldWriterOfEvaluationListEvaluation.getEvaluationList().remove(evaluationListEvaluation);
oldWriterOfEvaluationListEvaluation = em.merge(oldWriterOfEvaluationListEvaluation);
}
}
for (Book bookListBook : writer.getBookList()) {
Writer oldWriterOfBookListBook = bookListBook.getWriter();
bookListBook.setWriter(writer);
bookListBook = em.merge(bookListBook);
if (oldWriterOfBookListBook != null) {
oldWriterOfBookListBook.getBookList().remove(bookListBook);
oldWriterOfBookListBook = em.merge(oldWriterOfBookListBook);
}
}
utx.commit();
} catch (Exception ex) {
try {
utx.rollback();
} catch (Exception re) {
throw new RollbackFailureException("An error occurred attempting to roll back the transaction.", re);
}
throw ex;
} finally {
if (em != null) {
em.close();
}
}
}
public void edit(Writer writer) throws IllegalOrphanException, NonexistentEntityException, RollbackFailureException, Exception {
// remainder of code goes here
}
public void destroy(Integer id) throws IllegalOrphanException, NonexistentEntityException, RollbackFailureException, Exception {
// remainder of code goes here
}
public List<Writer> findWriterEntities() {
return findWriterEntities(true, -1, -1);
}
public List<Writer> findWriterEntities(int maxResults, int firstResult) {
return findWriterEntities(false, maxResults, firstResult);
}
private List<Writer> findWriterEntities(boolean all, int maxResults, int firstResult) {
EntityManager em = getEntityManager();
try {
CriteriaQuery cq = em.getCriteriaBuilder().createQuery();
cq.select(cq.from(Writer.class));
Query q = em.createQuery(cq);
if (!all) {
q.setMaxResults(maxResults);
q.setFirstResult(firstResult);
}
return q.getResultList();
} finally {
em.close();
}
}
public Writer findWriter(Integer id) {
EntityManager em = getEntityManager();
try {
return em.find(Writer.class, id);
} finally {
em.close();
}
}
public int getWriterCount() {
EntityManager em = getEntityManager();
try {
CriteriaQuery cq = em.getCriteriaBuilder().createQuery();
Root<Writer> rt = cq.from(Writer.class);
cq.select(em.getCriteriaBuilder().count(rt));
Query q = em.createQuery(cq);
return ((Long) q.getSingleResult()).intValue();
} finally {
em.close();
}
}
}