JSF 2.0 初学Demo

发表于

目录结构：


Root


–Web Pages


        –login.xhtml


        –index.html


        –error.html


        –WEB-INF


                  –web.xml


–sources Packages


        –org


                  –b3log


                            –application


                                      –Login.java


                            –entity


                                      –User.java


pom.xml


 



  • 去除 XML 配置



          JSF2.0省去了大量的陪值，主要原因是纳入了Facelets。省去了faces-config.xml中的大量配置。




    <managed-bean>
       <managed-bean-name>user</managed-bean-name>
       <managed-bean-class>
          com.corejsf.UserBean
       </managed-bean-class>
       <managed-bean-scope>session</managed-bean-scope>
    </managed-bean> 




  • 导航配置的简化



不需要


<navigation-rule>
  <navigation-case>
    <from-view-id>/pages/login.xhtml</from-view-id>
    <outcome>places</outcome>
    <to-view-id>/pages/places.xhtml</to-view-id>
  </navigation-case>
</navigation-rule>







 







这样复杂的导航规则，只需要通过约定进行绝对路径来进行导航便可。







例如







<h:form>
            <h:commandLink action="login" value="Back"/>
        </h:form>















就可以直接跳转到同一级目录下的login.xhtml页面。







也可以根据java 应用代码中返回的String来进行页面的跳转。







例如







public String login(final String password) {

        if (password.equals("Vanessa")) {

            return "index";

        }

        return "error";

    }










  • EL表达式的加强



以往 JSF 的表达式不支持参数的传递，现在我们可以通过配置相关的配置文件来实现


1.通过 Maven 获取需要的依赖


    <dependencies>
        <dependency>
            <groupId>javax.el</groupId>
            <artifactId>el-api</artifactId>
            <version>2.1.2-b05</version>
        </dependency>
        <dependency>
            <groupId>org.jboss.el</groupId>
            <artifactId>jboss-el</artifactId>
            <version>2.0.1.GA</version>
        </dependency>
    </dependencies>
<repositories>
        <repository>
            <id>sun</id>
            <url>http://download.java.net/maven/2/</url&gt;
        </repository>
        <repository>
            <id>java.net</id>
            <url>http://download.java.net/maven/2</url&gt;
        </repository>
        <repository>
            <id>jboss.org</id>
            <url>http://repository.jboss.org/maven2</url&gt;
        </repository>
    </repositories>



 


2. 在 web.xml 中配置一个 expressionFactory




   <context-param>

        <param-name>com.sun.faces.expressionFactory</param-name>

        <param-value>org.jboss.el.ExpressionFactoryImpl</param-value>

    </context-param>






3.就可以使用 EL 表达式传入一个对象


eg:


<h:commandButton value="Login" action="#{login.login(user.password)}"/>


 


 


应用解说


用户输入用户名和密码，进行登录


    1.登录成功–密码为“Vanessa”，进入 index.xhtml 页面，显示：Welcome，#{user.userName}!


    2.登录失败–密码不为“Vanessa”，进入 error.xhtml 页面，提示错误原因，点击Back后返回index.xhtml


 


 


部分代码


        –login.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"&gt;
<html xmlns="http://www.w3.org/1999/xhtml&quot;
      xmlns:h="http://java.sun.com/jsf/html"&gt;
    <head>
        <title>Welcome Login</title>
    </head>
    <body>
        <h:form>
            <h:panelGrid columns="2">
                <h:outputLabel for="userName" value="User Name"/>
                <h:inputText id="userName" value="#{user.userName}"/>
                <h:outputLabel for="password" value="Password"/>
                <h:inputSecret id="password" value="#{user.password}"/>
                <h:outputLabel value=""/>
                <h:commandButton value="Login" action="#{login.login(user.password)}"/>
            </h:panelGrid>
        </h:form>
    </body>
</html>



        –index.html


<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;
<html xmlns="http://www.w3.org/1999/xhtml"&gt;
    <head>
        <title>Index</title>
    </head>
    <body>
        Welcome, #{user.userName}!
    </body>
</html>



        –error.html


<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;
<html xmlns="http://www.w3.org/1999/xhtml&quot;
      xmlns:h="http://java.sun.com/jsf/html"&gt;
    <head>
        <title>Error</title>
    </head>
    <body>
        The Password is Error!
        <h:form>
            <h:commandLink action="login" value="Back"/>
        </h:form>
    </body>
</html>



        –Login.java


/
  To change this template, choose Tools | Templates
  and open the template in the editor.
 /
package org.b3log.application.jsf;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
import org.b3log.entity.User;
/
 
  @author Vanessa
 */
@ManagedBean(name = "login")
@SessionScoped
public class Login {
    public String login(final String password) {
        if (password.equals("Vanessa")) {
            return "index";
        }
        return "error";
    }
}



        –User.java


package org.b3log.entity;
import java.io.Serializable;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;
/
  This class depicts a user of B3log. This class only describes  user’s
  information basically, such as user name, email address, etc. The security
  information(i.e. user password, user roles, etc) is depicted in class
  <code>UserAccount</code>.
 
  @author <a href="mailto:lly219@gmail.com" mce_href="mailto:lly219@gmail.com">Liyuan Li</a>
  @version 1.0.0.0, Aug 4, 2009
  @see UserAccount
 */
@ManagedBean(name = "user")
@SessionScoped
public class User implements Serializable {
    private String userName;
    private String email;
    private String password;
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }
    public String getUserName() {
        return userName;
    }
    public void setUserName(String userName) {
        this.userName = userName;
    }
    public String getPassword() {
        return password;
    }
    public void setPassword(String password) {
        this.password = password;
    }
}