Hello World!

..sorry had to do it. Welcome to my first dev.to post, hopefully the first of many!

I wanted to start off with a really simple utility that Java developers can easily integrate in their code and improve the codebase.

Something I see very often, usually in legacy projects, is a logger being declared for every class.

1   public class MyClass {
2 
3       private static Logger logger = LoggerFactory.getLogger(MyClass.class);
4
5   ...
6   }

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Realistically this won’t be very resource intensive but we can definitely make improvements to simplify.

You don’t know what it is, but it’s there, like a splinter in your mind, driving you mad

Introducing.. logging with CDI!

With CDI, we can inject a SL4J (or your favourite implementation) logger.

First thing we need to do is implement a logging producer using the Injection Point API.

1   @ApplicationScoped
2   public class LoggerProducer {
3
4      @Produces
5      public Logger getLogger(final InjectionPoint ip) {
6          return LoggerFactory.getLogger(ip.getMember().getDeclaringClass());
6      }
7   }

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We specify the scope of the class as @ApplicationScoped. The injection point API allows us to know the declaring class of the injected logger.

Imports :

import javax.enterprise.context.ApplicationScoped;
import javax.enterprise.inject.Produces;
import javax.enterprise.inject.spi.InjectionPoint;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

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Note : Ensure that the correct @Produces annotation is imported, not the JAX-RS producer

Next step is to simply @Inject our logger into our class and begin to log.

1   @ApplicationScoped
2   public class MyClass {
3 
4       @Inject
5       private Logger logger;
6       
7       public void myMethod(){
8          logger.info("My log!");
9       }
10   }

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There we have it, an easy CDI logger.

There are other implementations such as a Lombok logger. However, there are some steps to make Lombok compatible with your IDE and I believe a CDI logger is easier to integrate with an existing codebase.

原文链接：Log Log Log .. how to deforest with Java CDI