Bean没有实例化 [英] Bean not instantiated
本文介绍了Bean没有实例化的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
正在使用的平台：
- Fedora 20;
- mariadb-5.5.34-2.fc20.x86_64;
- 来自www.eclipse.org的Eclipse Kepler服务版本;
- Apache TomEE plus 1.6 .0。
我正在实施示例
我正努力设法登录界面。我的问题是Login.xhtml的Java Bean尚未实例化。这怎么可能？我对java Beans非常熟悉，我检查了错误，这个例子来自一位专业的Java程序员。
我发现了这个问题，因为我没有设法登录，调试器没有显示任何变量。
Eclipse：调试Java EE中没有显示变量
我附上了login.xhtml和Java bean。我省略了GUI库，因为我认为它们不是问题的一部分。
Login.xhtml
< ui：composition template =/ templates / layout.xhtml
xmlns =http://www.w3.org/1999/xhtml
xmlns：f =http://java.sun.com/jsf/core
xmlns：h =http://java.sun.com/jsf/html
xmlns：ui =http://java.sun.com/jsf/facelets
xmlns：p =http://primefaces.org/ui
>
< ui：define name =content>
< h：form styleClass =loginPanelStyle>
< p：growl id =msgsshowDetail =truesticky =false/>
< p：panelGrid columns =2>
< f：facet name =header>
登录面板
< / f：facet>
< h：outputText value =用户名：>< / h：outputText>
< p：inputText id =usernamevalue =＃{loginController.username}required =truerequiredMessage =请输入用户名！消息= FC >
< f：validateLength minimum =1/>
< / p：inputText>
< h：outputText value =密码：>< / h：outputText>
< p：password id =passwordvalue =＃{loginController.password}required =truerequiredMessage =Please Enter password！>
< f：validateLength minimum =1/>
< / p：密码>
< f：facet name =footer>
< p：commandButton value =Submitupdate =msgsactionListener =＃{loginController.login}type =submiticon =ui-icon-checkstyle =margin：0 >< / p：的commandButton>
< / f：facet>
< / p：panelGrid>
< / h：form>
< / ui：define>
< / ui：composition>
LoginController.java
包控制器;
import util.DateUtility;
import java.io.IOException;
import java.io.Serializable;
import java.security.Principal;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.enterprise.context.SessionScoped;
import javax.faces.application.FacesMessage;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;
import javax.inject.Inject;
import javax.inject.Named;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
/ **
*登录控制器类仅允许经过身份验证的用户登录Web
*应用程序。
*
* @author Emre Simtay< emre@simtay.com>
* /
@Named
@SessionScoped
公共类LoginController实现Serializable {
@Inject
private transient Logger logger;
private String username;
私有字符串密码;
/ **
*创建一个新的LoginController实例
* /
public LoginController（）{
System.out.println（che diamine ）;
}
// Getters and Setters
/ **
* @return username
* /
public String getUsername（）{
返回用户名;
}
/ **
*
* @param username
* /
public void setUsername（String username）{
this.username = username;
}
/ **
*
* @return密码
* /
public String getPassword（）{
return密码;
}
/ **
*
* @param密码
* /
public void setPassword（String password）{
this.password =密码;
}
/ **
*听取＃{loginController.login}动作的按钮点击，
*验证用户输入的用户名和密码，导航到
*相应的页面。
*
* @param actionEvent
* /
public void login（ActionEvent actionEvent）{
System.out.println（CONSOLE PRINT TEST）;
FacesContext context = FacesContext.getCurrentInstance（）;
HttpServletRequest request =（HttpServletRequest）context.getExternalContext（）。getRequest（）;
try {
String navigateString =;
//检查用户名和密码是否有效，如果没有抛出ServletException
request.login（用户名，密码）;
//获取用户原则并导航到适当的页面
Principal principal = request.getUserPrincipal（）;
if（request.isUserInRole（Administrator））{
navigateString =/ admin /AdminHome.xhtml;
} else if（request.isUserInRole（Manager））{
navigateString =/ manager / ManagerHome.xhtml;
} else if（request.isUserInRole（User））{
navigateString =/ user / UserHome.xhtml;
}
尝试{
logger.log（Level.INFO，用户（{0}）登录＃+ DateUtility.getCurrentDateTime（），request.getUserPrincipal（）。getName（） ）;
context.getExternalContext（）。redirect（request.getContextPath（）+ navigateString）;
} catch（IOException ex）{
logger.log（Level.SEVERE，IOException，Login Controller+Username：+ principal.getName（），ex）;
context.addMessage（null，new FacesMessage（Error！，Exception Ocured））;
}
} catch（ServletException e）{
logger.log（Level.SEVERE，e.toString（））;
context.addMessage（null，new FacesMessage（Error！，您提供的用户名或密码与我们的记录不符。））;
}
}
/ **
*听取＃{loginController.logout}动作
*的退出按钮点击并导航到登录界面。
* /
public void logout（）{
HttpSession session =（HttpSession）FacesContext.getCurrentInstance（）。getExternalContext（）。getSession（false）;
HttpServletRequest request =（HttpServletRequest）FacesContext.getCurrentInstance（）。getExternalContext（）。getRequest（）;
logger.log（Level.INFO，User（{0}）loging out＃+ DateUtility.getCurrentDateTime（），request.getUserPrincipal（）。getName（））;
if（session！= null）{
session.invalidate（）;
}
FacesContext.getCurrentInstance（）。getApplication（）。getNavigationHandler（）。handleNavigation（FacesContext.getCurrentInstance（），null，/ LOGin.xhtml？facess-redirect = true）;
}
}
TomEE控制台：
web.xml
文件夹树：
$ tree
。 $ b $b├──build$ b $b│└──class$ b $b│├──Controller$ b $b││└──LoginController.class$ b $b│├──实体
││├──地址.class $ b $b││├──BaseEntity.class$ b $b││├──OrRole.class $ b $b││└──User.class$ b $b│ ├──META-INF $ b $b││└──persistence.xml$ b $b│└──util$ b $b│└──DateUtility.class$ b $b├──src
│├──控制器$ b $b││└──LoginController.java$ b $b│├──实体$ b $b││├──地址.java $ b $b││├──BaseEntity.java $ b $b││├──Role.java$ b $b││└──User.java$ b $b│├──META-INF $ b $b││└──persistence.xml
│└──util$ b $b│└──DateUtility.java $ b $b└──WebContent$ b $b├──admin$ b $b│├──AdminHome.xhtml$ b $b│└──UserList.xhtml$ b $b├──ErrorAccessDenied.xhtml$ b $b├──Login.xhtml$ b $b├──经理$ b $b│└──ManagerHome.xhtml$ b $b├──META-INF $ b $b│└──MANIFEST.MF$ b $b├──资源$ b $b│├──css$ b $b││└──default.css$ b $b│└──primefaces-nz $ b $b│├──图片
││├──ui-bg_flat_30_cccccc_40x100.png $ b $b││├──ui-bg_flat_50_5c5c5c_40x100.png $ b $b││├──ui-bg_glass_40_ffc73d_1x400.png $ b $b││├──ui- bg_highlight-hard_20_16475f_1x100.png $ b $b││├──ui-bg_highlight-soft_33_1258bf_1x100.png $ b $b││├──ui-bg_highlight-soft_35_222222_1x100.png
│├──ui-bg_highlight-soft_44_444444_1x100.png $ b $b││├──ui-bg_highlight-soft_80_1442c8_1x100.png $ b $b││├──ui-bg_inset-hard_30_dedede_1x100.png $ b $b││├ ──ui-icons_222222_256x240.png $ b $b││├──ui-icons_292cd1_256x240.png $ b $b││├──ui-icons_a83300_256x240.png $ b $b││├──ui-icons_cccccc_256x240.png $ b $b││└──ui-icons_ffffff_256x240.png $ b $b│└──meas.css$ b $b├──模板$ b $b│├──sqown.xhtml$ b $b│└─ ─瓷砖$ b $b│└──LeftMenu.xhtml$ b $b├──用户$ b $b│└──UserHome.xhtml$ b $b└──WEB-INF $ b $b├──面-config.xml $ b $b├──lib$ b $b└──web.xml
24个目录，41个文件
解决方案
你的web.xml是什么？你在* .html或* .jsf或其他地方映射了jsf页面吗？
如果你希望使用CDI，你在WEB-INF中有一个beans.xml吗？ / p>
Platform I am using:
- Fedora 20;
- mariadb-5.5.34-2.fc20.x86_64;
- Eclipse Kepler Service Release from www.eclipse.org;
- Apache TomEE plus 1.6.0.
I am implementing example
and I am trying to manage to work the login interface. My problem is that the Java Bean of Login.xhtml has not been instantiated. How is it possible? I am quite familiar with java Beans, I checked for errors and the example comes from an expert Java programmer. I found out this trouble because I did not manage to work the login, and the debugger showed no variables. Eclipse: no shown variables in debugging Java EE
I attach the login.xhtml and the Java bean. I omit the GUI libraries because I think they are not part of the problem.
Login.xhtml
<ui:composition template="/templates/layout.xhtml"
xmlns="http://www.w3.org/1999/xhtml"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:p="http://primefaces.org/ui"
>
<ui:define name="content">
<h:form styleClass="loginPanelStyle">
<p:growl id="msgs" showDetail="true" sticky="false" />
<p:panelGrid columns="2">
<f:facet name="header">
Login Panel
</f:facet>
<h:outputText value="Username : "></h:outputText>
<p:inputText id="username" value="#{loginController.username}" required="true" requiredMessage="Please Enter Username!" message="fc">
<f:validateLength minimum="1" />
</p:inputText>
<h:outputText value="Password : "></h:outputText>
<p:password id="password" value="#{loginController.password}" required="true" requiredMessage="Please Enter password!">
<f:validateLength minimum="1" />
</p:password>
<f:facet name="footer">
<p:commandButton value="Submit" update="msgs" actionListener="#{loginController.login}" type="submit" icon="ui-icon-check" style="margin:0"></p:commandButton>
</f:facet>
</p:panelGrid>
</h:form>
</ui:define>
</ui:composition>
LoginController.java
package controller;
import util.DateUtility;
import java.io.IOException;
import java.io.Serializable;
import java.security.Principal;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.enterprise.context.SessionScoped;
import javax.faces.application.FacesMessage;
import javax.faces.context.FacesContext;
import javax.faces.event.ActionEvent;
import javax.inject.Inject;
import javax.inject.Named;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
/**
* Login Controller class allows only authenticated users to log in to the web
* application.
*
* @author Emre Simtay <emre@simtay.com>
*/
@Named
@SessionScoped
public class LoginController implements Serializable {
@Inject
private transient Logger logger;
private String username;
private String password;
/**
* Creates a new instance of LoginController
*/
public LoginController() {
System.out.println("che diamine");
}
// Getters and Setters
/**
* @return username
*/
public String getUsername() {
return username;
}
/**
*
* @param username
*/
public void setUsername(String username) {
this.username = username;
}
/**
*
* @return password
*/
public String getPassword() {
return password;
}
/**
*
* @param password
*/
public void setPassword(String password) {
this.password = password;
}
/**
* Listen for button clicks on the #{loginController.login} action,
* validates the username and password entered by the user and navigates to
* the appropriate page.
*
* @param actionEvent
*/
public void login(ActionEvent actionEvent) {
System.out.println("CONSOLE PRINT TEST");
FacesContext context = FacesContext.getCurrentInstance();
HttpServletRequest request = (HttpServletRequest) context.getExternalContext().getRequest();
try {
String navigateString = "";
// Checks if username and password are valid if not throws a ServletException
request.login(username, password);
// gets the user principle and navigates to the appropriate page
Principal principal = request.getUserPrincipal();
if (request.isUserInRole("Administrator")) {
navigateString = "/admin/AdminHome.xhtml";
} else if (request.isUserInRole("Manager")) {
navigateString = "/manager/ManagerHome.xhtml";
} else if (request.isUserInRole("User")) {
navigateString = "/user/UserHome.xhtml";
}
try {
logger.log(Level.INFO, "User ({0}) loging in #" + DateUtility.getCurrentDateTime(), request.getUserPrincipal().getName());
context.getExternalContext().redirect(request.getContextPath() + navigateString);
} catch (IOException ex) {
logger.log(Level.SEVERE, "IOException, Login Controller" + "Username : " + principal.getName(), ex);
context.addMessage(null, new FacesMessage("Error!", "Exception occured"));
}
} catch (ServletException e) {
logger.log(Level.SEVERE, e.toString());
context.addMessage(null, new FacesMessage("Error!", "The username or password you provided does not match our records."));
}
}
/**
* Listen for logout button clicks on the #{loginController.logout} action
* and navigates to login screen.
*/
public void logout() {
HttpSession session = (HttpSession) FacesContext.getCurrentInstance().getExternalContext().getSession(false);
HttpServletRequest request = (HttpServletRequest) FacesContext.getCurrentInstance().getExternalContext().getRequest();
logger.log(Level.INFO, "User ({0}) loging out #" + DateUtility.getCurrentDateTime(), request.getUserPrincipal().getName());
if (session != null) {
session.invalidate();
}
FacesContext.getCurrentInstance().getApplication().getNavigationHandler().handleNavigation(FacesContext.getCurrentInstance(), null, "/Login.xhtml?faces-redirect=true");
}
}
TomEE console:
web.xml
folder tree:
$ tree
.
├── build
│ └── classes
│ ├── controller
│ │ └── LoginController.class
│ ├── entity
│ │ ├── Address.class
│ │ ├── BaseEntity.class
│ │ ├── Role.class
│ │ └── User.class
│ ├── META-INF
│ │ └── persistence.xml
│ └── util
│ └── DateUtility.class
├── src
│ ├── controller
│ │ └── LoginController.java
│ ├── entity
│ │ ├── Address.java
│ │ ├── BaseEntity.java
│ │ ├── Role.java
│ │ └── User.java
│ ├── META-INF
│ │ └── persistence.xml
│ └── util
│ └── DateUtility.java
└── WebContent
├── admin
│ ├── AdminHome.xhtml
│ └── UserList.xhtml
├── ErrorAccessDenied.xhtml
├── Login.xhtml
├── manager
│ └── ManagerHome.xhtml
├── META-INF
│ └── MANIFEST.MF
├── resources
│ ├── css
│ │ └── default.css
│ └── primefaces-nz
│ ├── images
│ │ ├── ui-bg_flat_30_cccccc_40x100.png
│ │ ├── ui-bg_flat_50_5c5c5c_40x100.png
│ │ ├── ui-bg_glass_40_ffc73d_1x400.png
│ │ ├── ui-bg_highlight-hard_20_16475f_1x100.png
│ │ ├── ui-bg_highlight-soft_33_1258bf_1x100.png
│ │ ├── ui-bg_highlight-soft_35_222222_1x100.png
│ │ ├── ui-bg_highlight-soft_44_444444_1x100.png
│ │ ├── ui-bg_highlight-soft_80_1442c8_1x100.png
│ │ ├── ui-bg_inset-hard_30_dedede_1x100.png
│ │ ├── ui-icons_222222_256x240.png
│ │ ├── ui-icons_292cd1_256x240.png
│ │ ├── ui-icons_a83300_256x240.png
│ │ ├── ui-icons_cccccc_256x240.png
│ │ └── ui-icons_ffffff_256x240.png
│ └── theme.css
├── templates
│ ├── layout.xhtml
│ └── tiles
│ └── LeftMenu.xhtml
├── user
│ └── UserHome.xhtml
└── WEB-INF
├── faces-config.xml
├── lib
└── web.xml
24 directories, 41 files
解决方案
What's your web.xml? did you map jsf pages on *.html or *.jsf or other?
Do you have a beans.xml in WEB-INF if you expect to use CDI?
这篇关于Bean没有实例化的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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