Java: using annotations for logging user operation instead of injection?

Question

I have a Java EE project with a lot of beans and processing. I was asked to log every dangerous operation that a user can do, i.e. deleting a document. I have a log method in userServices bean, so a call like this:

userService("is deleting the document with id: "+documentId);

will work, the bean will use jpa to store user, date, time and message in the log table. Anyway with this method I have to add the injection

@EJB private UserService userService;

in every EJB where I want to log something, and I really don't like it. I'm trying to use annotations and interceptor to do something like that:

@Stateless
@Interceptors(LogUserInterceptor.class)
@LogUserModuleName("Documents")
class DocumentServices implements DocumentServiceRemote {
    [...lot of code...]
    @Override
    @LogUserDangerousOperation("Delete a document")
    public deleteDocument(int id) {
    }
}

In my interceptor I combine the class annotation and the method annotation to create a message (in this case: "Document: Delete a document") and then I call userService.log(message). The advantage is I only have to annotate methods and class, without have to inject UserService bean programmatically call it. It's working fine, but the obvious point is that I have no way to pass the id of the document the user is deleting, so I cannot log "Document: Delete document 12345".

Is there a way to do it without injecting UserServices bean in almost every bean of my project?

Answer 1

Try using CDI Interceptors instead of EJB interceptors. They are much more powerful and flexible.

All you have to do is to declare them in beans.xml like this:

<beans xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/beans_1_0.xsd">
<interceptors>
    <class>custom.interceptor.Logger</class>
</interceptors>

Create annotation binding @Logger and create LoggerInterceptor like described in documentation.

Answer 2

yes.

Maybe you can try https://github.com/yeecode/ObjectLogger

Its a powerful and easy-to-use object log system, supports writing and querying of object attribute changes.

you can log any changes of any objects by it.