我正在尝试获取我能找到的与 Tomcat 一起使用的最简单的 JSF 示例:JavaEE 7 SDK 下载中的 javaee-tutorial/examples/web/jsf/hello1 示例。这是 official tutorial 的示例用来向您介绍 JSF。 (完全公开——我是 JSF 的新手，但不是 Java 或 Tomcat。)所有文件都直接来自 JavaEE SDK 示例——当然，Oracle 希望你使用 Glassfish 和 Netbeans，而不是 Tomcat 和 IntelliJ，所以我我正在尝试添加必要的依赖项以使其编译和运行。
到目前为止它编译并运行良好，但是当我按下表单上的“提交”按钮时，而不是另一个页面显示“你好，你的名字在这里!”我收到一个错误页面:
An Error Occurred:
/index.xhtml @20,43 value="#{hello.name}": Target Unreachable, identifier 'hello' resolved to null
- Stack Trace
javax.el.PropertyNotFoundException: /index.xhtml @20,43 value="#{hello.name}": Target Unreachable, identifier 'hello' resolved to null
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:100)
at com.sun.faces.renderkit.html_basic.HtmlBasicInputRenderer.getConvertedValue(HtmlBasicInputRenderer.java:95)
at javax.faces.component.UIInput.getConvertedValue(UIInput.java:1046)
at javax.faces.component.UIInput.validate(UIInput.java:976)
at javax.faces.component.UIInput.executeValidate(UIInput.java:1249)
at javax.faces.component.UIInput.processValidators(UIInput.java:712)
at javax.faces.component.UIForm.processValidators(UIForm.java:253)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1258)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1258)
at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1195)
at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76)
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:198)
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:646)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.doRun(AprEndpoint.java:2440)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:2429)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:744)
Caused by: javax.el.PropertyNotFoundException: Target Unreachable, identifier 'hello' resolved to null
at org.apache.el.parser.AstValue.getTarget(AstValue.java:97)
at org.apache.el.parser.AstValue.getType(AstValue.java:81)
at org.apache.el.ValueExpressionImpl.getType(ValueExpressionImpl.java:171)
at com.sun.faces.facelets.el.TagValueExpression.getType(TagValueExpression.java:98)
... 34 more
- Component Tree
<UIViewRoot id="j_id1" inView="true" locale="en_US" renderKitId="HTML_BASIC" rendered="true" transient="false" viewId="/index.xhtml">
javax_faces_location_HEAD
<ComponentResourceContainer id="javax_faces_location_HEAD" inView="true" rendered="true" transient="false">
<UIOutput id="__rf_skinning_resource" inView="true" rendered="true" transient="false"/>
</ComponentResourceContainer>
<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
<UIOutput id="j_idt2" inView="true" rendered="true" transient="false">
<title>Facelets Hello Greeting</title>
</UIOutput>
<HtmlBody id="j_idt4" inView="true" rendered="true" transient="false">
<HtmlForm enctype="application/x-www-form-urlencoded" id="j_idt5" inView="true" prependId="true" rendered="true" submitted="true" transient="false">
<HtmlGraphicImage alt="Duke waving his hand" id="j_idt6" inView="true" ismap="false" rendered="true" transient="false" url="/hello1/javax.faces.resource/duke.waving.gif.xhtml?ln=images" value="/hello1/javax.faces.resource/duke.waving.gif.xhtml?ln=images"/>
<h2>Hello, my name is Duke. What's yours?</h2>
<HtmlInputText disabled="false" id="username" immediate="false" inView="true" localValueSet="false" maxlength="25" readonly="false" rendered="true" required="true" requiredMessage="Error: A name is required." size="-2147483648" submittedValue="yournamehere" title="My name is: " transient="false" valid="true"/>
<p/>
<HtmlCommandButton action="response" actionExpression="response" disabled="false" id="submit" immediate="false" inView="true" readonly="false" rendered="true" transient="false" type="submit" value="Submit"/>
<HtmlCommandButton disabled="false" id="reset" immediate="false" inView="true" readonly="false" rendered="true" transient="false" type="reset" value="Reset"/>
</HtmlForm>
<div class="messagecolor">
<HtmlMessages errorStyle="color: #d20005" globalOnly="false" id="j_idt10" inView="true" infoStyle="color: blue" layout="list" redisplay="true" rendered="true" showDetail="false" showSummary="true" tooltip="false" transient="false"/>
</div>
</HtmlBody>
</html>
</UIViewRoot>
- Scoped Variables
Request Parameters
Name Value
j_idt5 j_idt5
j_idt5:submit Submit
j_idt5:username yournamehere
View Attributes
Name Value
None
Request Attributes
Name Value
None
Flash Attributes
Name Value
None
Session Attributes
Name Value
None
Application Attributes
Name Value
csfcff [ ]
Mar 21, 2015 11:15:56 AM - Generated by Mojarra/Facelets
我试过清理目标目录、重建项目、谷歌搜索这个错误——没有成功。而且这个错误看起来非常严重 - 我没有做任何改变。
显然某处存在断开连接，但我不知道它会是什么，并且如果没有一个工作示例来与之比较就很难弄清楚。
这是我修改过的 POM 文件，其他都是现成的，来自 Oracle 示例:
<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.glassfish.javaeetutorial</groupId>
<artifactId>hello1</artifactId>
<version>7.0.5</version>
<packaging>war</packaging>
<name>${project.artifactId}</name>
<properties>
<javaee.api.version>7.0</javaee.api.version>
<jsfVersion>2.2.6</jsfVersion>
<tomcat.version>7.0.55</tomcat.version>
</properties>
<dependencies>
<!-- ********************* JavaEE stuff ************************* -->
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-api</artifactId>
<version>${javaee.api.version}</version>
<scope>provided</scope>
</dependency>
<!-- ********************** JSF Dependencies ************************************* -->
<dependency>
<groupId>com.sun.faces</groupId>
<artifactId>jsf-impl</artifactId>
<version>${jsfVersion}</version>
</dependency>
<dependency>
<groupId>com.sun.faces</groupId>
<artifactId>jsf-api</artifactId>
<version>${jsfVersion}</version>
</dependency>
<dependency>
<groupId>com.sun.faces</groupId>
<artifactId>jsf-impl</artifactId>
<version>${jsfVersion}</version>
</dependency>
<!-- **************************** RichFaces Dependencies *********************** -->
<dependency>
<groupId>org.richfaces</groupId>
<artifactId>richfaces</artifactId>
<version>4.5.3.Final</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.1.2.Final</version>
</dependency>
<!-- ************************** Tomcat dependency to get web.xml stuff to resolve in Intellij -->
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>tomcat-catalina</artifactId>
<version>7.0.55</version>
<scope>provided</scope>
</dependency>
</dependencies>
</project>
有人能发现什么吗？
最佳答案
如果您想在 Tomcat 中使用该示例，您有两个选项，将 CDI 添加到 tomcat，您可以查看此 link这也描述了您面临的问题，或者您可以以这种方式使用 JSF ManagedBeans 而不是 CDI
import javax.faces.bean.ManagedBean
import javax.faces.bean.RequestScoped
@ManagedBean
@RequestScoped
public class Hello {
private String name;
public Hello() {
}
public String getName() {
return name;
}
public void setName(String user_name) {
this.name = user_name;
}
}
检查导入它们是与示例不同的包
关于jsf - Oracle Java EE 7 JSF 示例不适用于 Tomcat，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/29186417/