I'm fairly new to java servlets and have been following this tutorial. I have several issues initializing parameters; all values retrieved from web.xml seem to be NULL. The code that throws the exception is:
public class LoginServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public void init() throws ServletException {
//we can create DB connection resource here and set it to Servlet context
System.out.println("Check the string getServletContext().getInitParameter(\"dbURL\") = " + getServletContext().getInitParameter("dbURL")); // <== exception is thrown at this line
if(getServletContext().getInitParameter("dbURL").equals("jdbc:mysql://localhost/mysql_db") &&
getServletContext().getInitParameter("dbUser").equals("mysql_user") &&
getServletContext().getInitParameter("dbUserPwd").equals("mysql_pwd"))
getServletContext().setAttribute("DB_Success", "True");
else throw new ServletException("DB Connection error");
}
...
}
getServletContext.getInitParameter("anyParameter") returns the NULL string for every parameter value passed.
The web.xml file has the following entries:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID" version="3.0">
<display-name>DynamicWebProject1</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
<welcome-file>login.html</welcome-file>
</welcome-file-list>
<context-param>
<param-name>dbURL</param-name>
<param-value>jdbc:mysql://localhost/mysql_db</param-value>
</context-param>
<context-param>
<param-name>dbUser</param-name>
<param-value>mysql_user</param-value>
</context-param>
<context-param>
<param-name>dbUserPwd</param-name>
<param-value>mysql_pwd</param-value>
</context-param>
</web-app>
I am currently using eclipse kepler, jdk 7 and apache-tomcat-7.0.47 on a Win 7 x64 platform.
Edit:
The stacktrace:
javax.servlet.ServletException: Servlet.init() for servlet sebi.first.LoginServlet threw exception
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
java.lang.Thread.run(Unknown Source)
root cause
java.lang.NullPointerException
javax.servlet.GenericServlet.getServletContext(GenericServlet.java:125)
sebi.first.LoginServlet.init(LoginServlet.java:32)
javax.servlet.GenericServlet.init(GenericServlet.java:160)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041)org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
java.lang.Thread.run(Unknown Source)
I am not sure why you get org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
in the stacktrace. But if you are overriding init(config) try this:
public void init(ServletConfig config) throws ServletException {
super.init(config);
/* and rest of the things here */
}
Related
I have a jax rs web services in eclipse, they run well on our test server but throw an exception on my local machine when i try to run them in eclipse.
Below is the error it throws
Message Servlet.init() for servlet ServletAdaptor threw exception
Description The server encountered an unexpected condition that
prevented it from fulfilling the request.
Exception
javax.servlet.ServletException: Servlet.init() for servlet
ServletAdaptor threw exception
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:494)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1136)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Unknown Source)
Root Cause
java.lang.TypeNotPresentException: Type
javax.persistence.PersistenceUnit not present
sun.reflect.generics.factory.CoreReflectionFactory.makeNamedType(Unknown
Source)
sun.reflect.generics.visitor.Reifier.visitClassTypeSignature(Unknown
Source) sun.reflect.generics.tree.ClassTypeSignature.accept(Unknown
Source)
sun.reflect.generics.visitor.Reifier.reifyTypeArguments(Unknown
Source)
sun.reflect.generics.visitor.Reifier.visitClassTypeSignature(Unknown
Source) sun.reflect.generics.tree.ClassTypeSignature.accept(Unknown
Source)
sun.reflect.generics.repository.ClassRepository.getSuperInterfaces(Unknown
Source) java.lang.Class.getGenericInterfaces(Unknown Source)
com.sun.jersey.core.spi.factory.InjectableProviderFactory.getMetaArguments(InjectableProviderFactory.java:135)
com.sun.jersey.core.spi.factory.InjectableProviderFactory.add(InjectableProviderFactory.java:93)
com.sun.jersey.core.spi.factory.InjectableProviderFactory$1.onAdd(InjectableProviderFactory.java:109)
com.sun.jersey.core.spi.factory.InjectableProviderFactory$1.onAdd(InjectableProviderFactory.java:107)
com.sun.jersey.core.spi.component.ProviderServices.getProvidersAndServices(ProviderServices.java:204)
com.sun.jersey.core.spi.factory.InjectableProviderFactory.configure(InjectableProviderFactory.java:106)
com.sun.jersey.server.impl.application.WebApplicationImpl._initiate(WebApplicationImpl.java:1153)
com.sun.jersey.server.impl.application.WebApplicationImpl.access$700(WebApplicationImpl.java:180)
com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:799)
com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:795)
com.sun.jersey.spi.inject.Errors.processWithErrors(Errors.java:193)
com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:795)
com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:790)
com.sun.jersey.spi.container.servlet.ServletContainer.initiate(ServletContainer.java:509)
com.sun.jersey.spi.container.servlet.ServletContainer$InternalWebComponent.initiate(ServletContainer.java:339)
com.sun.jersey.spi.container.servlet.WebComponent.load(WebComponent.java:605)
com.sun.jersey.spi.container.servlet.WebComponent.init(WebComponent.java:207)
com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:394)
com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:577)
javax.servlet.GenericServlet.init(GenericServlet.java:158)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:494)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:1025)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1136)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:318)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Unknown Source)
Root Cause
Below is the eclipse project web.xml file
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
<display-name>leaveMgt</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>ServletAdaptor</servlet-name>
<servlet-class>com.sun.jersey.server.impl.container.servlet.ServletAdaptor</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value>webServices</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>ServletAdaptor</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>
</web-app>
Seems to me that the cause is a missing library in your classpath. Specifically, you have some classes annotated with #javax.persistence.PersistenceUnit, but this class is missing from the classpath. So I suggest you list all the libraries deployed in the test webserver (including the /lib libraries) and compare them with the ones deployed in your local server, paying special attention to some of these:
persistence.jar
javaee-api-*.jar
annotations-api-*.jar
.. which are the standard libraries in which javax.persistence.PersistenceUnit class might be present.
I have a simple REST API i am trying to get running and it's giving me a HTTP 404 error. AFAICS it looks right but obv not ...
Tomcat is running and i get the Eclipse browser come up with HTTP404. Tomcat doesnt help with all its errors but they are all just warnings but i can pop them in here if needed, will clutter the question though.
I think its to do with the jersey format, the xml or both but not sure.
*****Updated the question to include a xml update and a tomcat error.******
My class is thus:
package WS;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
//annotations
#Path("/book")
public class Book{
#GET
#Produces(MediaType.TEXT_XML)
public String sayHelloXML(){
String response = "<?xml version='1.0'?><hello>Hello there</hello>";
return response;
}
}
My Xml is thus: (note i think im using jersey 2.0 so i dont have to have anything here right?)
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
<display-name>RestApi</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>MyApplication</servlet-name>
<servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>jersey.config.server.provider.packages</param-name>
<!-- The package where your resource classes are -->
<param-value>WS</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>MyApplication</servlet-name>
<url-pattern>/api/*</url-pattern>
</servlet-mapping>
</web-app>
... and my libs imported is thus:
SEVERE: Allocate exception for servlet MyApplication
java.lang.ClassNotFoundException:
org.glassfish.jersey.servlet.ServletContainer at
org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1333)
at
org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1167)
at
org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:520)
at
org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:501)
at
org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:120)
at
org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1095)
at
org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:817)
at
org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:135)
at
org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at
org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
at
org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
at
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
at
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)
at
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
at
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Unknown Source)
Error i get back in browser when i hit http://localhost:8080/PK_WS/api/
javax.servlet.ServletException: Error instantiating servlet class
org.glassfish.jersey.servlet.ServletContainer
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Unknown Source)
root cause java.lang.ClassNotFoundException:
org.glassfish.jersey.servlet.ServletContainer
org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1333)
org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1167)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:616)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:518)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1091)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:673)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1500)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1456)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Unknown Source)
That's not enough in the web.xml. You still need to configure Jersey, as it's the runtime that handle the JAX-RS processing. You can either do it with web.xml
<servlet>
<servlet-name>MyApplication</servlet-name>
<servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>jersey.config.server.provider.packages</param-name>
<!-- The package where your resource classes are -->
<param-value>WS</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>MyApplication</servlet-name>
<url-pattern>/api/*</url-pattern>
</servlet-mapping>
Or without web.xml
#ApplicationPath("/api")
public class MyApplication extends ResourceConfig {
public MyApplication() {
packages("WS");
}
}
With both options, /api will be the app url prefix. You can change it.
For more information check out Servlet Based Deployment from the Jersey User Guide.
I am trying to create a REST Web Service that uses Jersey. I have created any .java files I need but when I run it on the server, it can never find it. My current web.xml file is as follows :-
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>com.epware.jersey.books</display-name>
<servlet>
<servlet-name>Jersey REST Service</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value>com.epware.jersey.books.resources</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Jersey REST Service</servlet-name>
<url-pattern>/rest/*</url-pattern>
</servlet-mapping>
</web-app>
What is important to note is that there is nothing within the server or server mapping fields in the 'Deployment Descriptor'. Could this by why it doesn't run?
Any help is greatly appreciated.
EDIT
The problem was due to a misplacement of the web.xml file. All cleared up. Despite this, I am now receiving the following error:
type Exception report
message Error instantiating servlet class
org.glassfish.jersey.spi.container.servlet.ServletContainer
description The server encountered an internal error that prevented it
from fulfilling this request.
EXCEPTION
javax.servlet.ServletException: Servlet.init() for servlet Jersey REST Service threw exception
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Unknown Source)
ROOT CAUSE
com.sun.jersey.api.container.ContainerException: The ResourceConfig instance does not contain any root resource classes.
com.sun.jersey.server.impl.application.RootResourceUriRules.<init>(RootResourceUriRules.java:99)
com.sun.jersey.server.impl.application.WebApplicationImpl._initiate(WebApplicationImpl.java:1298)
com.sun.jersey.server.impl.application.WebApplicationImpl.access$700(WebApplicationImpl.java:169)
com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:775)
com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:771)
com.sun.jersey.spi.inject.Errors.processWithErrors(Errors.java:193)
com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:771)
com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:766)
com.sun.jersey.spi.container.servlet.ServletContainer.initiate(ServletContainer.java:488)
com.sun.jersey.spi.container.servlet.ServletContainer$InternalWebComponent.initiate(ServletContainer.java:318)
com.sun.jersey.spi.container.servlet.WebComponent.load(WebComponent.java:609)
com.sun.jersey.spi.container.servlet.WebComponent.init(WebComponent.java:210)
com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:373)
com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:556)
javax.servlet.GenericServlet.init(GenericServlet.java:158)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:501)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:950)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1070)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:611)
org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:314)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Unknown Source)
Again I have no idea whatr is going on or how to fix it so any help is appreciated.
I just started learning Java for Web Developers today. I am following a tutorial in the book chapter 2. I have checked it line by line and everything is the same. I do not know enough about it yet to figure out the problem. Here is my error:
exception
javax.servlet.ServletException: Error instantiating servlet class apress.helloworld.HelloWorld
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:526)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:655)
org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:222)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1566)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1523)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Unknown Source)
root cause
java.lang.ClassNotFoundException: apress.helloworld.HelloWorld
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1324)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1177)
org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:503)
org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:526)
org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078)
org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:655)
org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:222)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1566)
org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1523)
java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
java.lang.Thread.run(Unknown Source)
Here is my code:
package apress.helloworld;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class HellowWorld extends HttpServlet {
protected void doGet(HttpServletRequest request, HttpServletResponse response) {
try {
response.setContentType("text/html");
PrintWriter printWriter = response.getWriter();
printWriter.println("<h2>");
printWriter.println("hello World!");
printWriter.println("</h2>");
} catch (IOException ioException) {
ioException.printStackTrace();
}
}
}
and web.xml (not sure if its relevant or not)
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
<display-name>helloworld</display-name>
<servlet>
<servlet-name>HelloWorld</servlet-name>
<servlet-class>apress.helloworld.HelloWorld</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>HelloWorld</servlet-name>
<url-pattern>/hello</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
</web-app>
Can anyone help me with this so I can learn java??
You have typo in the class name (additional 'w'). Fix, recompile and world will be beautiful again. Remember to change file name to match class name. ;)
public class HellowWorld extends HttpServlet
In the error message you got, the bottom line of the first portion says "Unknown Source" and that may be because it cannot find your class. This is because you have it under the package "apress.helloworld" but spelled your class name as "HellowWorld". Fix the class name and everything should be up and running.
I have the following configuration in my web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID" version="3.0">
<display-name>tycoon-sa</display-name>
<context-param>
<param-name>br.com.caelum.vraptor.encoding</param-name>
<param-value>UTF-8</param-value>
</context-param>
<error-page>
<location>/</location>
</error-page>
<filter>
<filter-name>vraptor</filter-name>
<filter-class>br.com.caelum.vraptor.VRaptor</filter-class>
</filter>
<filter-mapping>
<filter-name>vraptor</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>FORWARD</dispatcher>
<dispatcher>REQUEST</dispatcher>
<dispatcher>ERROR</dispatcher>
</filter-mapping>
</web-app>
My goal is to redirect the user to the main page in case of exceptions or error codes (404, 500, etc). But it's not working. I've tried to access an invalid URL and I was not redirected. The application throws a NullPointerException. Here's the stack trace:
SEVERE: Servlet.service() for servlet default threw exception
java.lang.NullPointerException
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:321)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at br.com.caelum.vraptor.resource.DefaultResourceNotFoundHandler.couldntFind(DefaultResourceNotFoundHandler.java:41)
at br.com.caelum.vraptor.interceptor.ResourceLookupInterceptor.intercept(ResourceLookupInterceptor.java:71)
at br.com.caelum.vraptor.core.ToInstantiateInterceptorHandler.execute(ToInstantiateInterceptorHandler.java:54)
at br.com.caelum.vraptor.core.DefaultInterceptorStack.next(DefaultInterceptorStack.java:54)
at br.com.caelum.vraptor.core.EnhancedRequestExecution.execute(EnhancedRequestExecution.java:44)
at br.com.caelum.vraptor.VRaptor$1.insideRequest(VRaptor.java:91)
at br.com.caelum.vraptor.ioc.spring.SpringProvider.provideForRequest(SpringProvider.java:58)
at br.com.caelum.vraptor.VRaptor.doFilter(VRaptor.java:88)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:749)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:489)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:412)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:339)
at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:456)
at org.apache.catalina.core.StandardHostValve.status(StandardHostValve.java:327)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:193)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1002)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:585)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Abr 02, 2013 11:04:32 AM org.apache.catalina.core.StandardHostValve custom
SEVERE: Exception Processing ErrorPage[errorCode=0, location=/]
java.lang.NullPointerException
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:321)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at br.com.caelum.vraptor.resource.DefaultResourceNotFoundHandler.couldntFind(DefaultResourceNotFoundHandler.java:41)
at br.com.caelum.vraptor.interceptor.ResourceLookupInterceptor.intercept(ResourceLookupInterceptor.java:71)
at br.com.caelum.vraptor.core.ToInstantiateInterceptorHandler.execute(ToInstantiateInterceptorHandler.java:54)
at br.com.caelum.vraptor.core.DefaultInterceptorStack.next(DefaultInterceptorStack.java:54)
at br.com.caelum.vraptor.core.EnhancedRequestExecution.execute(EnhancedRequestExecution.java:44)
at br.com.caelum.vraptor.VRaptor$1.insideRequest(VRaptor.java:91)
at br.com.caelum.vraptor.ioc.spring.SpringProvider.provideForRequest(SpringProvider.java:58)
at br.com.caelum.vraptor.VRaptor.doFilter(VRaptor.java:88)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:749)
at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:489)
at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:412)
at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:339)
at org.apache.catalina.core.StandardHostValve.custom(StandardHostValve.java:456)
at org.apache.catalina.core.StandardHostValve.status(StandardHostValve.java:327)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:193)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:929)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1002)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:585)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Any clues?
this is the way to configure a default error page for all the errors
<error-page>
<location>/whateverpage.html</location>
</error-page>
Remember this will only work if you are using Servlet 3.0. if you are still using Servlet 2.5 then you will have to specify each and every error code.
<error-page>
<error-code>404</error-code>
<location>/notfound.html</location>
</error-page>
<error-page>
<error-code>403</error-code>
<location>/general-error.html</location>
</error-page>
error-page can not rediect invalid url .If you want to do that you can use apache server and write following
RewriteEngine on
Redirect /--xyz-75/ http://www.domain.com.au/
Specify the error code in your error page tag
404
/ErrorPage.jsp