I'm trying to inject a ManagedBean in my FacesConverted the following way:
#ManagedBean
#RequestScoped
#FacesConverter(forClass = Group.class)
public class GroupConverter implements Converter {
#ManagedProperty("#{groupService}")
private GroupService groupService;
#Override
public Group getAsObject(FacesContext context, UIComponent arg1,
String groupName) {
return groupService.findGroupByName(groupName);
}
#Override
public String getAsString(FacesContext arg0, UIComponent arg1, Object group) {
return ((Group) group).getName();
}
public GroupService getGroupService() {
return groupService;
}
public void setGroupService(GroupService groupService) {
this.groupService = groupService;
}
}
The problem is that groupService isn't being injected and I get a NullPointerEx. Shouldn't it be autowired automatically since it's also a ManagedBean? It all works when I change "getAsObject" to "return new Group();" obviously.
Any ideas?
It is likely that you are not resolving the managed bean name.
#ManagedBean(name = "myConverter")
#RequestScoped
#FacesConverter(value = "myConverter")
public class MyConverter implements Converter {
For example, consider these two components:
<h:inputText converter="myConverter" value="#{foo.prop}" />
<h:inputText converter="#{myConverter}" value="#{bar.prop}" />
When the converter is set on the first component, it will be created by Application.createConverter. A converter is not a managed bean. The same rules apply if you match a converter by type.
In the second component, a value expression is used to return a class that implements Converter. This uses the usual managed bean mechanisms. In this case, the #FacesConverter annotation is irrelevant.
Related
Here is my code
Pojo
public class Deal implements Serializable {
private int id;
private String name;
private String description;
private Customer customer;
//getter setter omitted
}
public class Customer implements Serializable {
private int id;
private String name;
private String email;
private String phone;
//getter setter and equal hashcode omitted
}
Managed Bean
#ManagedBean(name="dealBean")
#ViewScoped
public class DealBean implements Serializable {
private List<Customer> customerList;
private List<Deal> dealList;
private Deal deal;
#PostConstruct
public void init() {
deal = new Deal();
dealList = new ArrayList<Deal>();
customerList = new ArrayList<Customer>();
customerList.add(new Customer(1, "MPRL", "mprl#mail.com", "1234455"));
customerList.add(new Customer(2, "Total", "total#mail.com", "3434323"));
customerList.add(new Customer(3, "Petronas", "petronas#mail.com", "8989876"));
}
//getter setter omitted
}
Customer Converter
#FacesConverter("customerConverter")
public class CustomerConverter implements Converter {
#Override
public Object getAsObject(FacesContext arg0, UIComponent arg1, String customerID) {
DealBean dealBean = (DealBean) FacesContext.getCurrentInstance().getExternalContext().getSessionMap().get("dealBean");
if (dealBean != null) {
List<Customer> customerList = dealBean.getCustomerList();
for (Customer customer : customerList) {
if (customerID.equals(String.valueOf(customer.getId()))) {
return customer;
}
}
}
return null;
}
#Override
public String getAsString(FacesContext arg0, UIComponent arg1, Object obj) {
if (obj != null) {
return String.valueOf(((Customer)obj).getId());
}
return null;
}
}
XHTML
Customer : <h:selectOneMenu id="customer" value="#{dealBean.deal.customer}">
<f:converter converterId="customerConverter" />
<f:selectItems value="#{dealBean.customerList}" var="cus"
itemLabel="#{cus.name}" itemValue="#{cus}" />
</h:selectOneMenu>
When the managed bean is in request or session scope, the Customer pojo is set correctly to Deal pojo. The problem is when the managed bean is in View scope, the Customer pojo is set to Deal pojo as NULL.
I am using JSF 2.2.0
Thanks much for the help in advance.
It's not the converter, is the view scoped the one broken:
Since you're using JSF tags, you cannot use #ViewScoped annotation, because it was removed from specification and recovered only for CDI usage. You could use omnifaces view scoped or the components of apache myFaces (I personally recommend omnifaces).
You can confirm this creating a
System.out.print("Creating");
in the constructor and checking how is called each Ajax request, so the bean is not recovered and since is marked as view and is a partial request, the values are not setted again (unless you send all the form, which is not a nice solution), other workaround could be making the bean request and recover all the data each request, making it Session (but will be alive for the session), or the #ConvesationScoped, in which you'll have to destroy and start the conversation manually.
Again, my first recommendation could be change to a Java ee server compliant and use the CDI annotations since JSF are being depreciated and not updated anymore
I'm trying to Write my own converter
I want to Inject my EJBs into my converter with #EJB .
my #EJB works in Other my ManagedBean but it doesn't work here in my converter
#ManagedBean
#ViewScoped
public class ServerTypeConverter implements Converter {
#EJB
private ServerTypeFacade serverTypeFacade;
#Override
public Object getAsObject(FacesContext context, UIComponent component, String value) {
if (value == null || value.isEmpty()) {
return null;
} else {
int id = Integer.parseInt(value);
return serverTypeFacade.findById(id);
}
}
#Override
public String getAsString(FacesContext context, UIComponent component, Object value) {
if (value == null || value.equals("")) {
return "";
} else {
Integer id = ((ServerType) value).getServer_type_id();
return String.valueOf(id);
}
}
}
ServerTypeFacade returns null. why ?
here is the way i use converter
<h:selectOneMenu value="#{serverMB.selectedServerType}">
<f:converter converterId="serverTypeConverter"/>
<f:selectItems value="#{serverMB.serverTypesList}" var="servertypes" itemLabel="#{servertypes.server_type_name}" />
<f:ajax listener="#{serverMB.changeServerType}" render="dd" />
</h:selectOneMenu>
The #EJB in converter works only if you declare it as a managed bean by #ManagedBean and use it as managed bean by #{serverTypeConverter}.
However, you're using the converter as a faces converter by converterId="serverTypeConverter". Apparently you've also declared it as a faces converter by #FacesConverter on the class or <converter> in faces-config.xml.
Those two ways of declaring and using the converter are mutually exclusive. In order to get #EJB to work, you should be using the converter as a managed bean:
<f:converter binding="#{serverTypeConverter}" />
See also:
CDI Injection into a FacesConverter
I want to get the value with the getter method, but it doesn't work. I use SessionScoped into my two managed-beans.
<h:outputLabel for="commentInput" value="Comment:" />
<p:inputTextarea id="commentInput" value="#{dashboardBean.currentComment}" rows="6" cols="25" label="commentInput" required="true"/>
#ManagedBean
#SessionScoped
public class DashboardBean implements Serializable
{
private String _currentComment = null;
public String getCurrentComment() {
return this._currentComment;
}
public void setCurrentComment(String _currentComment) {
this._currentComment = _currentComment;
}
}
If i call getter in this class, it's works.
But in the other class:
#ManagedBean
#SessionScoped
public class PanelListener extends AjaxBehaviorListenerImpl
{
private DashboardBean _dashDashboardBean = null;
public void editMemo(ActionEvent actionEvent)
{
System.out.println("Statements ==== [ " + _dashDashboardBean.getCurrentComment() + " ]");
}
}
I have an NullPointerException.
You need to use #ManagedProperty annotation to inject one bean into another.
#ManagedProperty("#{dashboardBean}")
private DashboardBean bean;
public DashboardBean getBean(){
return this.bean;
}
public void setBean(DashboardBean bean){
this.bean = bean;
}
Make sure the scope of the ManagedProperty is greater than or equal to the scope of bean in which you are injecting.
so here, DashBoardBean should have scope greater than or equal to PanelListener
Please note that JSF needs public getters and setters to access the fields
You have to use #ManagedProperty annotation. So try this in PanelListener, note that you need a setter to perform the bean injection. You can also only inject beana with greater or same scope to the bean with lower scopes (so for example you can inject SessionScoped to the RequestScoped but not the other way around).
#ManagedProperty("#{dashboardBean}")
private DashboardBean bean;
private void setDashboardBean(DashboardBean bean) {
this.bean = bean;
}
I have a JSF web application with a view-scoped bean and a session-scoped bean. I'd like to modify the session bean's members from the view bean, and I followed this guide from a certain well-known JSF guy, but I can't seem to get it to work without a runtime exception. The reference to the managed session bean, "home" is null when referenced, similar to this question except I've already followed the advice of the accepted answer.
package brian.canadaShipping;
import java.io.Serializable;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;
import javax.faces.bean.ViewScoped;
#ManagedBean(name= "requestBean")
#ViewScoped
public class CpstcRequestBean implements Serializable {
#ManagedProperty(value="#{home}")
private CpstcHomeBean homeBean;
public CpstcHomeBean getHomeBean() {
return homeBean;
}
public void setHomeBean(CpstcHomeBean homeBean) {
this.homeBean = homeBean;
}
private static final long serialVersionUID = -5066913533772933899L;
public String testVar = "hello world";
private boolean displayOutput = false;
public boolean isDisplayOutput() {
return displayOutput;
}
public void setDisplayOutput(boolean displayOutput) {
this.displayOutput = displayOutput;
}
public String getTestVar() {
return testVar;
}
public void setTestVar(String testVar) {
this.testVar = testVar;
}
public CpstcRequestBean()
{
System.out.println("TEST: " + homeBean.toString());
System.out.println("Hello, ResuestBean!");
}
}
The first bit of my "home" bean is as follows:
#ManagedBean(name= "home")
#SessionScoped
public class CpstcHomeBean implements Serializable {
...
UPDATE: I've followed Jordan's suggestions and I have the following in my view-scoped bean:
#ManagedBean(name= "requestBean")
#ViewScoped
public class CpstcRequestBean implements Serializable {
#Inject #Named("home") CpstcHomeBean homeBean;
public CpstcHomeBean getHomeBean() {
return homeBean;
}
public void setHomeBean(CpstcHomeBean homeBean) {
this.homeBean = homeBean;
}
public CpstcRequestBean()
{
System.out.println("TEST: " + homeBean.toString());
System.out.println("Hello, ResuestBean!");
}
...
as well as this in my session-scoped bean:
#Named("home")
#SessionScoped
public class CpstcHomeBean implements Serializable {
...
yet my "home" bean reference is still null. Any ideas?
UPDATE 2: It turns out that you must use #Named in both classes, not just the injected class. My web app now loads but some elements are blank. In my console log, I see, "Target Unreachable, identifier 'home' resolved to null." I'm running on Tomcat 7, if that affects things. Any ideas?
You can either change your session bean's #ManagedBean to #Named and then just inject it into your view scoped bean OR you can reference the session bean as is like this:
FacesContext fc = FacesContext.getCurrentInstance()
private CpstcHomeBean homeBean = (CpstcHomeBean) fc.getApplication().evaluateExpressionGet(fc, "#{home}", CpstcHomeBean.class);
I have this SearchBean:
#ManagedBean(name = "searchBean")
#RequestScoped
public class SearchBean implements Serializable
{
private String input = null;
// getter methods
public String getInput() {
return input;
}
// setter method
public void setInput(String input) {
this.input = input;
}
public String Submit() {
return null;
}
}
Can I inject it into another bean using #ManagedProperty. For example:
#ManagedBean(name = "bookBean")
#RequestScoped
public class BookBean implements Serializable
{
#ManagedProperty(value = "#{searchBean}")
private SearchBean searchBean;
#PostConstruct
public void init()
{
System.out.println("Value: " + searchBean.getInput());
}
public SearchBean getSearchBean() {
return searchBean;
}
public void setSearchBean(SearchBean searchBean) {
this.searchBean = searchBean;
}
}
And the Facelet (search.xhtml):
<h:form id="formSearch">
<h:commandButton value="Search" action="#{searchBean.Submit}" />
</h:form>
UPDATE: I have search.xhtml inserted into book.xhtml via a ui:insert component as follow:
<h:form id="formBooks">
<ui:insert name="search">
<ui:include src="/templates/common/search.xhtml"/>
</ui:insert>
</h:form>
The searchBean.getInput() method above should return a value as a result of a form's submission. Is the above method of injection possible?
I assume that SearchBean.input will be bound to an input field:
public class SearchBean implements Serializable {
private String input = null;
Something like this:
<h:inputText value="#{searchBean.input}" />
If so, then this will be null:
#PostConstruct
public void init()
{
System.out.println("Value: " + searchBean.getInput());
}
But, assuming a value has been set, it will not be null when this method is invoked:
public String Submit() {
return null;
}
Image from Richard Hightower's JSF for nonbelievers: The JSF application lifecycle.
The reason is due to how the JSF lifecycle works:
When #{searchBean...} is first resolved and found not to exist:
The bean is instantiated
Any dependency injections are performed (there aren't any in this case)
#PostConstruct method is invoked
The bean is placed into scope
Assuming the Apply Request Values and Validations phases succeed, SearchBean.setInput(String) is invoked in the Update Model Values phase
SearchBean.Submit() is invoked in the Invoke Application phase
This process is defined in the JSF specification.
Now, if SearchBean.input were injected directly from the parameter map, it would not be null during #PostConstruct:
#ManagedProperty(value = "#{param.someParamName}")
private String input;
However, there aren't any real advantages to this - you're skipping any input validation and you can't use SearchBean.input as a field binding because it will be overwritten in the Update Model Values phase.
The SearchBean.Submit() method is where your application logic for performing the search should go.