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我正在尝试开发一个简单的 Jsf 2.2.1 应用程序。我浏览了一些页面并找到了示例应用程序。我想尝试其中一个样品。我设置了每个依赖项和注释；但是，backing bean 不工作。我想做的是在 Jsf 页面上通过 bean 显示一些文本字段并呈现一些输入文本。Jsf 标记工作正常，但 bean 值未显示在页面上。在页面中，我有一个输入文本区域和一个命令按钮。这些组件显示在页面上，但我输入一些文本并按下命令按钮时遇到以下问题。我正在使用“mvn clean package”构建应用程序，然后将其部署在 Tomcat 7.x 上。

错误：

serverError: class javax.el.PropertyNotFoundException Target Unreachable, identifier 'helloWorld' resolved to null

在以下内容中，我将共享我的所有文件。

网页.xml：

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<display-name>helloworld</display-name>
<welcome-file-list>
    <welcome-file>home.xhtml</welcome-file>
</welcome-file-list>
<servlet>
    <servlet-name>Faces Servlet</servlet-name>
    <servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
    <servlet-name>Faces Servlet</servlet-name>
    <url-pattern>*.xhtml</url-pattern>
</servlet-mapping>
<context-param>
    <param-name>javax.faces.PROJECT_STAGE</param-name>
    <param-value>Development</param-value>
</context-param>

pom.xml：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.test</groupId>
<artifactId>helloworld</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>helloworld Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>com.sun.faces</groupId>
        <artifactId>jsf-api</artifactId>
        <version>2.2.1</version>
        <scope>compile</scope>
    </dependency>
    <dependency>
        <groupId>com.sun.faces</groupId>
        <artifactId>jsf-impl</artifactId>
        <version>2.2.1</version>
        <scope>compile</scope>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>servlet-api</artifactId>
        <version>2.5</version>
    </dependency>
            <dependency>
        <groupId>javax.el</groupId>
        <artifactId>el-api</artifactId>
        <version>2.2</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.glassfish.web</groupId>
        <artifactId>el-impl</artifactId>
        <version>2.2</version>
        <scope>provided</scope>
    </dependency>
</dependencies>

<build>
    <finalName>helloworld</finalName>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>2.3.1</version>
            <configuration>
                <source>1.5</source>
                <target>1.5</target>
            </configuration>
        </plugin>

    </plugins>
</build>
<repositories>
    <repository>
        <id>maven2-repository.dev.java.net</id>
        <name>java.net Repository for Maven</name>
        <url>http://download.java.net/maven/2</url>
    </repository>
</repositories>

Java Bean：HelloWorld.java

import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;
import javax.faces.bean.SessionScoped;

@ManagedBean(name="helloWorld")
@SessionScoped
public class HelloWorld {
private String name="Zaman Safari";
@ManagedProperty(value = "#{demoService}")
private Service service;
public HelloWorld(){
    System.out.println("HELLOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO");
}
public String getName(){
    return name;
}

public void setName(String name){
    this.name = name;
}

public void setService(Service service){
    this.service = service;
}

public String getReverse(){
    return service.reverse(name);
}
}

服务.java：

import javax.faces.bean.ApplicationScoped;
import javax.faces.bean.ManagedBean;

@ManagedBean(name="demoService")
@ApplicationScoped
public class Service {

public String reverse(String name) {
    return new StringBuffer(name).reverse().toString().toLowerCase();
}
}

我的文件中究竟缺少什么？

4

1 回答 1

0

PropertyNotFoundException意味着您的支持 bean 中没有getter/setter 属性方法。

HelloWorldBean.java

@ManagedBean(name="HelloWorldBean")
public calss HelloWorldBean {

    private String getHelloWorld() {
        return "Hello World!";
    }
}

我的页面

    <h:outputText value="#{HelloWorldBean.helloWorld}"/>
于 2013-07-17T09:45:58.290 回答