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[英]Why is it possible to @Inject a @Stateless EJB into a @SessionScoped Managed Bean?
[英]Why Managed Bean List becomes including null elements in sessionscoped?
我想獲取有關聯系人的一些信息並將其顯示在表格中。 我使用了兩個由PersonalContact
和BusinessContact
命名的托管bean和一個由Contact
命名的抽象類,其中包括mphone
派生的firstName
, lastName
, ID
, email
和mphone
屬性。還有一個通用類將bean添加到數組列表中。 我在這里僅將BusinessContact
作為一個bean,將Business作為XHTML和tableBusiness
作為一個表以及泛型類AddressBook
,personal文件與它們平行。
從屏幕獲取的輸入被分配給bean的屬性,但是當bean進入要添加的Arraylist
,其內容將為空。 這是為什么? 那是關於范圍的嗎?
這是我的豆子:
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ViewScoped;
@ManagedBean
@ViewScoped
public class BusinessContact extends Contact{
private String companyName,workPhone;
public BusinessContact() {}
public BusinessContact(String companyName, String workPhone, String ID, String firstName, String lastName, String email, String mphone) {
super(ID, firstName, lastName, email, mphone);
this.companyName = companyName;
this.workPhone = workPhone;
}
/**
* Creates a new instance of BusinessContact
*/
public String getCompanyName() {
return companyName;
}
public void setCompanyName(String companyName) {
this.companyName = companyName;
}
public String getWorkPhone() {
return workPhone;
}
public void setWorkPhone(String workPhone) {
this.workPhone = workPhone;
}
}
這是我的business.xhtml:
<?xml version='1.0' encoding='UTF-8' ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org /TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html"
xmlns:f="http://xmlns.jcp.org/jsf/core"
xmlns:ui="http://xmlns.jcp.org/jsf/facelets">
<h:head>
<title>Contact</title>
</h:head>
<h:body>
<h:form>
<h:panelGrid columns="2">
First Name:
<h:inputText id="firstName" required="true"
requiredMessage="Can not be blank" value="#{businessContact.firstName}">
</h:inputText>
ID:
<h:inputText id="id" required="true"
requiredMessage="Can not be blank" value="#{businessContact.ID}">
</h:inputText>
Last Name:
<h:inputText id="lastName" required="true"
requiredMessage="Can not be blank" value="#{businessContact.lastName}">
</h:inputText>
E-mail:
<h:inputText id="email" required="true"
requiredMessage="Can not be blank" value="#{businessContact.email}">
</h:inputText>
Mobile Phone:
<h:inputText id="mphone" required="true"
requiredMessage="Can not be blank" value="#{businessContact.mphone}">
</h:inputText>
Company Name:
<h:inputText id="companyName" required="true"
requiredMessage="Can not be blank" value="#{businessContact.companyName}">
</h:inputText>
Work Phone:
<h:inputText id="workPhone" required="true"
requiredMessage="Can not be blank" value="#{businessContact.workPhone}">
</h:inputText>
</h:panelGrid>
<h:commandButton value="Add" id="add" action="#{addressBook.add(BusinessContact)}"></h:commandButton>
<h:commandButton value="Delete" id="delete" action="#{addressBook.remove(BusinessContact)}"></h:commandButton>
<h:outputLink id="t" value="tableBusiness.xhtml"> Click see the table</h:outputLink>
<ui:debug hotkey="k" rendered="true"/>
</h:form>
</h:body>
這是用於將bean放入arraylist的通用類:
import java.util.ArrayList;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
@ManagedBean
@SessionScoped
public class AddressBook <T extends Contact> {
private ArrayList<T> list = new ArrayList<T>();
T clas;
public ArrayList<T> getList() {
return list;
}
public void setList(ArrayList<T> list) {
this.list = list;
}
public void add(T obj) {
this.clas=obj;
//System.out.println(obj.getFirstName()+" ");
list.add(obj);
}
public void remove(T obj)
{
list.remove(obj);
}
/**
* Creates a new instance of AddressBook
*/
public AddressBook() {}
}
最后,此xhmtl用於在表中顯示arraylist:
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:h="http://xmlns.jcp.org/jsf/html"
xmlns:f="http://xmlns.jcp.org/jsf/core">
<h:head>
</h:head>
<h:body>
<h:form>
"#{businessContact.firstName}"
<h:dataTable value="#{addressBook.list}" var="BusinessContact">
<h:column>
<f:facet name="header">
First Name
</f:facet>
<h:outputText value="#{businessContact.firstName}">
</h:outputText>
</h:column>
<h:column>
<f:facet name="header">
Last Name
</f:facet>
#{businessContact.lastName}
</h:column>
<h:column>
<f:facet name="header">
Mobile Phone
</f:facet>
#{businessContact.mphone}
</h:column>
<h:column>
<f:facet name="header">
E-mail
</f:facet>
#{businessContact.email}
</h:column>
<h:column>
<f:facet name="header">
Company Name
</f:facet>
#{businessContact.companyName}
</h:column>
<h:column>
<f:facet name="header">
Work Phone
</f:facet>
#{businessContact.workPhone}
</h:column>
</h:dataTable>
</h:form>
</h:body>
</html>
您正在命名var="BusinessContact"
但嘗試將其用作"businessContact"
更改此行
<h:dataTable value="#{addressBook.list}" var="BusinessContact">
對此
<h:dataTable value="#{addressBook.list}" var="businessContact">
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