Head fisrt servlets and jsp:- unable to run the first example

Hi all,

I am newbie to servlets and jsp. when i was trying to execute simple helloworld servlet, it is giving an error "description The requested resource (/first/HelloWorld/) is not available."

OS- > Win7
Tomcat -> 5.5

HelloWorld.java

web.xml

my directory structure is
webapps->first->WEB-INF->web.xml
webapps->first->WEB-INF->classes->HelloWorld.class

I am accesing that servlet via http://localhost:8080/first/HelloWorld

due to this error im stuck with the first example. how can i resolve this?
NB:- All those servlets and jsp examples coming with tomcat is working fine

Jasim Aboobacker

Check your Tomcat logs to see if there are any errors happening at startup. (check the "logs" directory)

Christophe

In log i can see some java.io.UnsupportedEncodingException

Feb 2, 2011 11:06:25 AM org.apache.catalina.startup.ContextConfig applicationWebConfig
SEVERE: Parse error in application web.xml file at jndi:/localhost/first/WEB-INF/web.xml
java.io.UnsupportedEncodingException: ISO-8851-1
	at sun.nio.cs.StreamDecoder.forInputStreamReader(Unknown Source)
	at java.io.InputStreamReader.<init>(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLEntityScanner.createReader(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLEntityScanner.setEncoding(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanXMLDeclOrTextDecl(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$XMLDeclDriver.next(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
	at org.apache.tomcat.util.digester.Digester.parse(Digester.java:1562)
	at org.apache.catalina.startup.ContextConfig.applicationWebConfig(ContextConfig.java:352)
	at org.apache.catalina.startup.ContextConfig.start(ContextConfig.java:1044)
	at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:261)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4148)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:760)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:740)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:544)
	at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:926)
	at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:889)
	at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:492)
	at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1149)
	at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:311)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:120)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1022)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:736)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1014)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:448)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:700)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:552)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:295)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:433)

Hey,

Now its working. i replaced encoding="ISO-8851-1" with encoding="ISO-8859-1" in web.xml

Thank you

Whoa! I didn't know encoding could also affect successful running of an application.
As the book says, we needn't memorize this all and I frankly thought it may create a glitch or two but not a total failure of the app.

Thanks for bringing this up, I can make sure to check all these things in future. :-)