Spring MVC + log4j example

In this post, we will see how to integrate Spring MVC with log4j.

Spring MVC tutorial:

Logging is essential part of programming. It helps developer to track code workflow and fix bugs efficiently. If we get any issue in the code, we check logs for that workflow or functionality.
Log4j is fast , reliable logging framework and can be easily integrated with the code.

We will extend Spring MVC hello world example and enable log4j logging into it.If you are wondering how to use log4j in maven project, you can follow log4j maven integration example.
You only need to follow below steps to enable log4j in Spring MVC.

Put log4j jar in classpath and you can use maven to do it for you by adding dependency to pom.xml.
Create log4j.properties and put it in the classpath (resource folder in maven)

Project structure:

Step 1:

Add log4j dependency in pom.xml for maven project. For non maven project , put log4j.jar in Web-INF/lib folder.


 log4j
 log4j
 1.2.17

Your pom.xml will look as below:


    4.0.0
    com.arpit.java2blog
    SpringMVCLog4JExample
    war
    0.0.1-SNAPSHOT
    SpringMVCLog4JExample Maven Webapp
    http://maven.apache.org
    

        
            junit
            junit
            3.8.1
            test
        

        
            javax.servlet
            javax.servlet-api
            3.1.0
        

        
            org.springframework
            spring-core
            ${spring.version}
        
        
            org.springframework
            spring-webmvc
            ${spring.version}
        
        
 log4j
 log4j
 1.2.17

    
    
        SpringMVCLog4JExample

        
            
                org.apache.maven.plugins
                maven-compiler-plugin
                3.1
                
                    ${jdk.version}
                    ${jdk.version}
                
            
        

    
    
        4.2.1.RELEASE
        1.6

Step 2:
Create log4j.properties as below and put it in the java/main/resources folder.

log4j.rootLogger=DEBUG, console, file

log4j.appender.console=org.apache.log4j.ConsoleAppender
log4j.appender.console.layout=org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=[%t] %-5p %c %x - %m%n

log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=[%t] %-5p %c %x - %m%n
log4j.appender.file.File=applicationLogs.log

Step 3:
Change HelloWorldController.java as below:

package org.arpit.java2blog.springmvc.controller;

import org.apache.log4j.Logger;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
public class HelloWorldController {

    private static final Logger logger = Logger.getLogger(HelloWorldController.class);
 @RequestMapping("/helloworld")
 public ModelAndView hello() {

  String helloWorldMessage = "Hello world from java2blog!";
    logger.info("This is info message");
    logger.error("This is error message");

  return new ModelAndView("hello", "message", helloWorldMessage);
 }
}

Step 4:
When you run the project, you will get below screen.