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I have read this tutorials it's an ebook and I'm stuck at deploying the JSP page to my tomcat server by the way it's a jsp page but it's using JSF tags I already put my javax.faces-2.1.13 jar at the lib, where is should really belong to..
Here is my JSP page title hello.jsp:
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@ taglib prefix="f" uri="http://java.sun.com/jsf/core"%>
<%@ taglib prefix="h" uri="http://java.sun.com/jsf/html"%>
<html>
<head>
<title>JSF In Action</title>
</head>
<body>
<f:view>
<h:form id="welcome-form">
<h:outputText id="welcomeOutput" value="Welcome to JavaServer Faces!" style="font-family: Arial, Sans-serif; font-size: 24; color: green;" />
<p><h:message id="error" for="helloInput" style="color: red;" /></p>
<p><h:outputLabel for="helloInput">
<h:outputText id="helloInputLabel" value="Enter Number of Controls to Display:" />
</h:outputLabel>
<h:inputText id="helloInput" value="#{ helloBean.numcontrol }" required="true">
<f:validateLongRange minimum="1" maximum="500" />
</h:inputText></p>
<p><h:panelGrid id="controlPanel" binding="#{ helloBean.controlPanel }" columns="20" border="1" cellspacing="0">
</h:panelGrid></p>
<h:commandButton id="redisplaycommand" type="submit" value="Redisplay" actionListener="#{ helloBean.addControl }" />
<h:commandButton id="goodbyecommand" type="submit" value="GoodBye" action="#{ helloBean.goodbye }" immediate="true" />
</h:form>
</f:view>
</body>
</html>
And this is the stack trace error that I get:
SEVERE: Servlet.service() for servlet [jsp] in context with path [/SampleJSF1] threw exception [An exception occurred processing JSP page /hello.jsp at line 5
2: <%@ taglib uri="http://java.sun.com/jsf/core" prefix="f" %>
3: <%@ taglib uri="http://java.sun.com/jsf/html" prefix="h" %>
4:
5: <f:view>
6: <html>
7: <head>
8: <title>
Stacktrace:] with root cause
java.lang.NullPointerException
at javax.faces.webapp.UIComponentClassicTagBase.setJspId(UIComponentClassicTagBase.java:1858)
at org.apache.jsp.hello_jsp._jspx_meth_f_005fview_005f0(hello_jsp.java:126)
at org.apache.jsp.hello_jsp._jspService(hello_jsp.java:100)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1002)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:585)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)
Anyone that can help guys I really appreciate it. :)
The
FacesContextisnullat that point. This means that theFacesServletdidn't do its job. The stacktrace is also evidence of this; the lineat javax.faces.webapp.FacesServlet.service()is missing.The request URL needs to match the
<url-pattern>of theFacesServletas you've configured in/WEB-INF/web.xmlin order to properly invoke it.So, if it's for example
<url-pattern>*.jsf</url-pattern>, then you should open the page by/hello.jsfinstead of/hello.jspin browser address bar.Unrelated to the concrete problem, JSP is deprecated since JSF 2.0. You should be discarding this legacy view technology and be looking at its successor Facelets. You should make absolutely sure that you aren't reading books/tutorials/resources targeted on JSF 1.x instead of JSF 2.x. A lot of things are done differently in JSF 2.x as opposed to 1.x, which would in long term only lead to confusion among starters.
See also: