java.lang.ClassFormatError: Absent Code attribute in method that is not native or abstract in class file javax/mail/Session

This happens if your code compiles against incomplete classes, like the JavaEE6 Api and your Unit tests try to access code thats not there. JUnit will simply fail and mark the test as error, printing something like this

Tests in error:
  initializationError(com.dominikdorn.dc.passwordReset.SimplePasswordResetServiceTest)

and the corresponding surefire text file starts like this:

-------------------------------------------------------------------------------
Test set: com.dominikdorn.dc.passwordReset.SimplePasswordResetServiceTest
-------------------------------------------------------------------------------
Tests run: 1, Failures: 0, Errors: 1, Skipped: 0, Time elapsed: 0.022 sec <<< FAILURE!
initializationError(com.dominikdorn.dc.passwordReset.SimplePasswordResetServiceTest)  Time elapsed: 0.005 sec  <<< ERROR!
java.lang.ClassFormatError: Absent Code attribute in method that is not native or abstract in class file javax/mail/Session
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:621)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
        at java.net.URLClassLoader.access$000(URLClassLoader.java:56)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
....

The Solution
You have to compile against real-implementations of the classes. You do that by adding those dependencies before the most generic dependency in your pom.xml

As example, we add javax.mail BEFORE javaee6-api like this

...
    

        
            javax.mail
            mail
            1.4
            provided
        
        
            javax
            javaee-api
            6.0
            provided
        

If you are deploying your App on an Appserver like Glassfish or JBoss AS, leave the scope of javax.mail:mail as provided to prevent the inclusion of the jar in the final webapp.

I now list required dependencies for various Absent Code Errors I've encountered and still encountering. This post will be updated every time I solve another of these problems.

JavaMail: javax/mail/Session

...
    
        
            javax.mail
            mail
            1.4
            provided
        
    

Servlet 3.0

...
    
               
                       org.glassfish
                       javax.servlet
                       3.0
                       provided
               
...
    
....
    
               
               
                       Glassfish
                       Glassfish Maven2 Repository
                       http://download.java.net/maven/glassfish/
               
    
 

JPA2: javax/persistence/PersistenceException

...
        
            org.eclipse.persistence
            javax.persistence
            2.0.0
            provided
        
...
..

...
    
...
        
            eclipse
            Eclipse Maven Repository
            http://www.eclipse.org/downloads/download.php?r=1&nf=1&file=/rt/eclipselink/maven.repo
        
    

JAX-RS: javax/ws/rs/core/UriBuilder

        
            com.sun.jersey
            jersey-core
            1.1.5
            provided
        

        
            com.sun.jersey
            jersey-json
            1.1.5
            provided
        

        
            com.sun.jersey
            jersey-test-framework
            1.1.5.1
            test
        

more to come soon!

To get this working again, simply create a css-class

.counterList li {display: block }
.counterList li:before {content: counter(start) ". "; counter-increment: start}

and surround your list with a tag like this

import javax.annotation.ManagedBean;
import javax.annotation.PostConstruct;
import javax.enterprise.context.RequestScoped;
import javax.faces.component.UIComponent;
import javax.faces.context.FacesContext;
import javax.faces.convert.Converter;
import javax.faces.convert.FacesConverter;
import javax.inject.Inject;

@FacesConverter(forClass = AvailableCountry.class)
@ManagedBean // does not help 
@RequestScoped // does not help 
public class AvailableCountryConverter implements Converter
{
	@Inject
	AvailableCountryDao dao;

	@PostConstruct
	public void postConstruct()
	{
		System.out.println("calling postConstruct");
	}

	public Object getAsObject(FacesContext facesContext, UIComponent
			component, String value) {
		if (value == null || value.length() == 0) {
			return null;
		}
		return dao.find(getKey(value));
	}

	Long getKey(String value) {
		Long key;
		key = Long.valueOf(value);
		return key;
	}

	String getStringKey(long value) {
		StringBuffer sb = new StringBuffer();
		sb.append(value);
		return sb.toString();
	}

	public String getAsString(FacesContext facesContext, UIComponent
			component, Object object) {
		if (object == null) {
			return null;
		}
		if (object instanceof AvailableCountry) {
			AvailableCountry o = (AvailableCountry) object;
			return getStringKey(o.getCountry().getId());
		} else {
			throw new IllegalArgumentException("object " + object + "
					is of type " + object.getClass().getName() + "; expected type: " +
					AvailableCountry.class.getName());
		}
	}
}

But my DAO was not injected, nor was the postConstruct method triggered by CDI.

Why?
Because the bean is not managed by CDI, not even when annotating it with @ManagedBean because it gets created by the JSF-Lifecycle and not by CDI.

Well.. but how to manually lookup a Bean with CDI / Weld?

First, you need to get the BeanManager. When you have a FacesContext (like in the converter above), you can get it like this:

    public BeanManager getBeanManager()
    {
        return (BeanManager)
              ((ServletContext) facesContext.getExternalContext().getContext())
                   .getAttribute("javax.enterprise.inject.spi.BeanManager");
    }

If you don’t have access to a FacesContext, ServletContext or similar, you can lookup the BeanManager through JNDI

    public BeanManager getBeanManager()
    {
        try{
            InitialContext initialContext = new InitialContext();
            return (BeanManager) initialContext.lookup("java:comp/BeanManager");
        catch (NamingException e) {
            log.error("Couldn't get BeanManager through JNDI");
            return null;
        }
    }

After you’ve got your BeanManager, simply lookup your Bean like this:
(In my case, I wanted to lookup a bean with the type AvailableCountryDao)
Type-based CDI manual lookup

    public AvailableCountryDao getFacade()
    {
        BeanManager bm = getBeanManager();
        Bean bean = (Bean) bm.getBeans(AvailableCountryDao.class).iterator().next();
        CreationalContext ctx = bm.createCreationalContext(bean);
        AvailableCountryDao dao = (AvailableCountryDao) bm.getReference(bean, AvailableCountryDao.class, ctx); // this could be inlined, but intentionally left this way
        return dao;
    }

Thanks to my friend Lincoln Baxter, III for the snipped.

Name-based CDI manual lookup

    public Object getBeanByName(String name) // eg. name=availableCountryDao
    {
        BeanManager bm = getBeanManager();
        Bean bean = bm.getBeans(name).iterator().next();
        CreationalContext ctx = bm.createCreationalContext(bean); // could be inlined below
        Object o = bm.getReference(bean, bean.getClass(), ctx); // could be inlined with return
        return o;
    }

So, now you’re able to manually lookup beans with CDI.
In case you have the same problem (with Converters/Validators) like I had above, checkout Seam Faces, where this problem already is fixed,
meaning your @ManagedBean annotated Converter/Validator is working as expected with @Inject, @PostConstruct & @PreDestroy

In our example, we want to match a URL like this one

http://www.studyguru.eu/at/tuwien/184.153--Entwurfsmethoden-fuer-verteilte-Systeme

Previously I tried to match it with a PrettyFaces Pattern/Regex like this:

But thankfully, PrettyFaces >2.0.4 supports directly populating the RequestParams!

Configure your pretty-config like this:

....

    

        /path/to/coursePage.xhtml
    
....

and use JSF2′s viewParams like this:

    
        
    

    
        
    
    
        
    

    

coursePage

countryCode #{ coursePageBean.countryCode} 

courseId #{coursePageBean.courseId}

universityCode #{coursePageBean.universityCode}

Voila! You now can match complex urls with PrettyFaces and apply all your custom validators
to your Pretty URL

A LoginContext Object is used by applications to authenticate users independently of the underlying authentication technology. Authentication technology in this context means stuff like “file based authentication”, “Database based authentication”, “LDAP authentication”, “CERTIFICATE authentication” and so on.

The LoginContext class is part of the javax.security.auth.login package and describes methods used to authenticate Subjects/user in the meaning of Part 1 of this series). The documentation states:

A subject is an identity in a system that you want to authenticate and assign access rights to. A subject can be a human user, a process, or a machine..

which is basically what I said before. Its still a little bit unclear to me, why they use “user” in one documentation and “subject” in the other, but as its the same thing, we know what to do.

The documentation further states, that a subject may interact with different authorities (applications) and may have different passwords (credentials) for each of them. To represent the subject/user in these applications, the java.security.Principal class is used.

Our own LoginContext now invokes various LoginModules ( these handle the different ways of authentication, like form based, HTTP-Basic, HTTP-Digest, etc.). The LoginModule interface is part of
the javax.security.auth.spi package. If one ever wants to integrate Facebook connect or something similar, this is where to look at!

But how does the LoginContext know, which LoginModules to invoke? This is done by a Configuration Object.

So, to sum this up:

1. We have 1-n LoginModules, handling different form of authentication.. file, db, ldap and so on
2. We have a LoginContext, taking users credentials and supplying them to the LoginModules
3. We have configurations, specifying which LoginModules should be used by the LoginContext
4. A client supplies its credentials to the LoginContext. The LoginContext looks up, which LoginModules to use in its Configuration and authenticates the client with the provided credentials against the LoginModules.

But why bother with all this stuff of LoginContext, LoginModules, Configuration and so on? Shouldn’t it be easy to use authentication, especially custom authentication in a web-app?

Because we’ve already got it in our AppServer!

Configuration:
We’re actually creating our Configuration object manually in our web.xml.

Here we define, how we gain the authentication data from the user. In this example, I used auth-method=FORM because no-one wants to use HTTP-Basic Authentication anymore today!

    
        FORM
        nameOfTheRealm

/login.xhtml
/loginError.xhtml
        
    

With this configuration, you can already create your own login form with your preferred style, like this:
login.xhtml

Userid

Password

In the next part of the series, we’ll see how you can do it with an jsf/facelets page.

Ok, we now got our form for login. To Logout simply make a link to /j_security_logout

We’ve now got login + logout, but they are not working yet. What we still have to do, is specify, what we’re authenticating against. In this post, we called it LoginModule, in Glassfishv3 its called Realm and we have already
configured it with our Login-Config above.

A post which explains how to configure the simply, build in Glassfish “File-Realm” is available at DevelopInJava.com.

In the next blog entry of this series, we’ll see how we can create our own realm, that really suits our needs.

We now got everything needed for a basic authentication, but we don’t yet have a group to role mapping, which we need for stuff like #{request.isUserInRole(‘ADMIN’)} or annotating our beans (see later for all of that).
So what we’re going to do is, map the given “groups” to roles. Before we do that, we should tell our application, which roles we have. Do it like that in your web.xml

    
        all the users with the role Admin
        ADMIN
    

    
        all the users that are authenticated
        LOGGEDIN_USER
    

    
        all the users that are moderators/extended rights
        MODERATOR
    

Now we can map the groups we get from the realm to our roles. We have to put this in
/WEB-INF/sun-web.xml (if you’re using Glassfish v3). My file looks like this:

    /
    
        LOGGEDIN_USER
        default
    
    
        MODERATOR
        moderatoren
    
    
        ADMIN
        root
    
    
    

            Keep a copy of the generated
                servlet class' java code.
        
    

Click here to view the general structure of the sun-web.xml file.

Our User -> Principal, Group -> Role mapping now works. We can start protecting resources in our app! Horray!

We’re doing this by specifying “security-constraints” like this in our web.xml

    
        
            admin-area
            /admin/
        
        
            admins should be allowed to access this resources
            ADMIN
        
    

This should be quite self-explanatory, for a detailed explanation take a look at
Security Annotations and Authorization in GlassFish and the Java EE 5 SDK, which also explains how to secure beans with annotations
and has a nice matrix whats possible with annotations and whats not.

If you want to lock some stuff for everyone, simply leave the auth-constraint element empty, like this:

    
        
            admin-area
            /admin/
        
        
        
    

If you’ve followed these instructions and the one on the blog-post Securing a Web Application on Glassfish using JAAS, you should now be able to authenticate different users with different roles in your app using the File-Realm.

In the next articles of the series, we will look how to create an own realm, how to replace the form-based login with a JSF-Based one and how to work with roles in your JSF-Pages.

References:

• Authentication in JSF2 with JAAS: Part 1 – Understand the terminology
• Java Authentication and Authorization Service (JAAS)in Java 2, Standard Edition (J2SE) 1.4
• Securing a Web Application on Glassfish using JAAS
• Structure of sun-web.xml file

How to resolve this? Encode the umlauts with their Unicode code in your message-bundle like this

1. ä = \u00e4
2. Ä = \u00c4
3. ö = \u00f6
4. Ö =\u00d6
5. ü = \u00fc
6. Ü = \u00dc
7. ß = \u00df

So, e.g. just specify it like this in your bundle.properties

homework=Haus\u00fcbung

Specify the bundle itself in your faces-config.xml

    
        
            /bundle
            bundle
        
    

and use it in your facelets page example.xhtml like this:

#{bundle.homework}

or like this

If you don’t want to convert all the Umlauts in your bundle by hand, simply use javas

native2ascii

command to automatically encode the Umlauts in your bundle.properties file.

Update:
I found this unicode chart, which I think is quite useful!

CHANGES:

• Replaced roles.isEmpty() with roles.equals(“”) to allow usage with Java 5
• Adopted taglib for usage with Spring 3/Spring Security 3 final
• removed faces-config.xml in taglibs for jsf 1.2 as it prevented deploying in some scenarios

Fetch it from the Project Homepage

I created a taglib based on the code of BalusC.
You can find the Taglib on Github

The source code is based on these two posts:

1. Uploading files in Servlet 3.0
2. Uploading files with JSF 2.0 and Servlet 3.0

Simply check out the code with git

git clone http://github.com/domdorn/fileUploadServlet3JSF2.git

then install the taglib with

mvn clean compile install

and import it into your maven project like this

net.balusc
fileUploadServlet3JSF2
1.0-SNAPSHOT

You can then use the taglib in your Facelets files like this:

Upload.xhtml

	

	

			
				SomeText:
			

			
				
			 

			
			Filename:
			

			
				
			
			
	
	

	
	
		
				Input File:
		
		
			
		
		
	
	

The bean:

package com.dominikdorn.simpleFileUpload.beans;

import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;
import javax.faces.bean.SessionScoped;
import javax.faces.bean.ViewScoped;
import java.io.File;

@ViewScoped
@ManagedBean
public class UploadBean {

private File file;
private String filename;

public String getFilename() {
return filename;
}

public void setFilename(String filename) {
System.out.println("binding filename");
this.filename = filename;
}

public String submit()
{
System.out.println("calling submit");

if(file != null)
{
this.filename = file.getName();
}

System.out.println("processed");
// do what you want with the file
return "yeah";
}

public UploadBean() {
}

public File getFile() {
return file;
}

public void setFile(File file) {
this.file = file;
}

private String someText;

public String getSomeText() {
return someText;
}

public void setSomeText(String someText) {
System.out.println("binding someText");
this.someText = someText;
}
}

Also take a look at the comments, there is some useful info there too!

I just tried it out and it really rocks! Download, extract, start domain, running!
Even PHP Applications are easily possible: I will look further into this this weekend!