8080 port already taken issue when trying to redeploy project from Spring Tool Suite IDE

I have strange thing when I try to modify Spring project inside my Spring Tool Suite. On the first load (deploy) everything is fine, application compiles and runs on localhost:8080

When I change something inside code and try to redeploy it (Run it again - Run As Spring Boot App) I get error message

*************************** APPLICATION FAILED TO START

---

Description:

The Tomcat connector configured to listen on port 8080 failed to start. The port may already be in use or the connector may be misconfigured.

Action:

Verify the connector's configuration, identify and stop any process that's listening on port 8080, or configure this application to listen on another port.

2016-10-19 00:01:22.615 INFO 10988 --- [ main] ationConfigEmbeddedWebApplicationContext : Closing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@3023df74: startup date [Wed Oct 19 00:01:19 CEST 2016]; root of context hierarchy 2016-10-19 00:01:22.616 INFO 10988 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Unregistering JMX-exposed beans on shutdown

If I shutdown process on that port manually everything works fine again, but this can't be right way of redeploying Spring app. Am I doing something wrong here?

I'm using :: Spring Boot :: (v1.4.1.RELEASE)

P.S. I'm aware that I can setup some kind of hot-swap mechanism to have automatic reload of page after I change code, but for now I would like to resolve this issue first.

Thanks for any kind of help or info.

It sometimes happen even when we stop running processes in IDE with help of Red button , we continue to get same error.

It was resolved with following steps,

1. Check what processes are running at available ports

   netstat -ao |find /i "listening"

   We get following

   TCP 0.0.0.0:7981 machinename:0 LISTENING 2428 TCP 0.0.0.0:7982 machinename:0 LISTENING 2428 TCP 0.0.0.0:8080 machinename:0 LISTENING 12704 TCP 0.0.0.0:8500 machinename:0 LISTENING 2428

   i.e. Port Numbers and what Process Id they are listening to

2. Stop process running at your port number(In this case it is 8080 & Process Id is 12704)

   Taskkill /F /IM 12704 (Note: Mention correct Process Id)

For more information follow these links Link1 and Link2.

My Issue was resolved with this, Hope this helps !

For Mac users(OS X El Capitan):

You need to kill the port that localhost:8080 is running on.
To do this, you need to do two commands in the terminal :N

sudo lsof -i tcp:8080

kill -15 PID 

NB! PID IS A NUMBER PROVIDED BY THE FIRST COMMAND.

The first command gives you the PID for the localhost:8080.
Replace the PID in the second command with the PID that the first command gives you to kill the process running on localhost:8080.

You have to stop the current process and run your new one. In Eclipse, you can press this button to ReLaunch your application:

The reason is one servlet container is already running on port 8080 and you are trying to run another one on port 8080.

• 1. Check what processes are running at available ports.

     • For Windows :

     • netstat -ao |find /i "listening"

     OR

     • netstat -ano | find "8080" (Note: 8080 is port fail to start)

• 2. Now try to reLaunch or stop your application.

     • To relaunch: you can press this button

  

  • To stop in windows:

  Taskkill /F /IM 6592 Note: Mention correct Process Id

  

  right click on the console and select terminate/disconnect all

  • Go to Task Manager and end Java(tm) platform se binary

  

  What is java(tm) platform se binary(Search in google

Another option is :

Go to application.properties file set server.port=0. This will cause Spring Boot to use a random free port every time it starts.

In my case, the error occurred as the application was unable to access the keystore for ssl.

Starting the application as root user fixed the issue.