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Not able to access the docker containerised java web app on exposed port

I have Java web app in docker container.
Now container is exposed on host's port 8080 from container's port 8080 by running docker run command.
docker run -d -p 8080:8080 --name myTomcat -v $(pwd)/out/artifacts/DockerJavaWebAppWarExploded:/usr/local/tomcat/webapps/ tomcat:latest
There is no other process running on 8080 port ,but i am not able to access the application from browser http://localhost:8080/.
Container logs :
Please help.
It would be appreciated.

Check if http://0.0.0.0:8080 returns values. If yes, you may add an enrty for 0.0.0.0 in your hosts file.

Spring boot jar docker deployment throwing Connection Exception with MySQL Container

I just started exploring docker today and I've been trying to spin-up Spring Boot Web app backed by MySQL DB.
I pulled a MySQL container and ran it using:
docker run -t --name mysql-docker-container -p 3306:3306 -e MYSQL_ROOT_PASSWORD=**** -e MYSQL_DATABASE=spring_app_db -e MYSQL_USER=app_user -e MYSQL_PASSWORD=**** -d mysql
My application.properties file:
spring.datasource.url=jdbc:mysql://0.0.0.0:3306/spring_app_db?autoReconnect=true&failOverReadOnly=false&maxReconnects=10
spring.datasource.username=app_user
spring.datasource.password=test123
spring.jpa.hibernate.ddl-auto=create-drop
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL5Dialect
with this, when I run my spring boot in IDE it's able to connect and perform CRUD on db table.
However, when I try to deploy it on docker and link with MySQL container it throws Connection Refused error.
My Dockerfile:
FROM openjdk:11
LABEL maintainer="baljinder#gmail.com"
VOLUME /tmp
EXPOSE 8080
ADD target/demo-0.0.1-SNAPSHOT.jar bootmysql.jar
ENTRYPOINT ["java", "-jar", "bootmysql.jar"]
The command I'm using to run docker image of the boot:
docker run -t --name spring-jpa-container -p 8080:8080 --link mysql-docker-container:mysql spring-jpa-app
Can someone please help with this. I've tried deploying both on the same container network by creating a docker network (docker network create -d bridge sql_spring_network) but the error persists.

When using the legacy linking of containers using the --link flag. The "linked" container is available as a host in the running container with it's container name. So in your case, the mysql container is available in your app container with hostname mysql.
Your database url, therefore should be: jdbc:mysql://mysql:3306/spring_app_db?autoReconnect=true&failOverReadOnly=false&maxReconnects=10

use:
jdbc:mysql://mysql-docker-container:3306/spring_app_db?autoReconnect=true&failOverReadOnly=false&maxReconnects=10
replace:
jdbc:mysql://0.0.0.0:3306/spring_app_db?autoReconnect=true&failOverReadOnly=false&maxReconnects=10

how to access mysql docker container in spring boot docker container

i have 2 docker file
1. mysql-dockerfile
FROM mysql:5.5
EXPOSE 3306
ENV MYSQL_ROOT_PASSWORD root
ENV MYSQL_DATABASE ToDoList
command used to build dockerfiles are as below
sudo docker build -t mysql-img -f mysql-dockerfile .
sudo docker run -d --name mysqlcontainer -p 3030:3306 mysql-img
2. java-dockerfile
FROM openjdk:8-jre-alpine
EXPOSE 9090
WORKDIR /usr/src
COPY target/*.war todoApp.war
CMD ["java","-jar","todoApp.war"]
command used to build dockerfiles are as below
sudo docker build -t java-img -f java-dockerfile .
docker run --name javacontainer -d -p 4040:9090 java-img
spring boot application consist jdbc url as follow
spring.datasource.url=jdbc:mysql://localhost:3030/ToDoList
i am not able to start project because spring boot application in docker is not able to connect mysql db which is in another container.
one solution i found is to bring two docker container in one docker network or link docker container.
can anyone please suggest good solution, modified docker run command and modified jdbc url.

Put them into one network and use container names as hostnames:
docker network create foo
docker run --network=foo --name mysqlcontainer -d mysql-img
docker run --network=foo --name javacontainer -d java-img
Dont expose ports - they are exposed automatically between containers inside network.
To connect inside, use mysqlcontainer:3306 and javacontainer:9090.
To connect from host, you will need port exposing.

Run a Docker Image as a Container (for windows users)

I built a docker image from a dockerfile. I see the image was built successfully (
$ docker images) and when I use this command to run the image as a container :
$ docker run -i -t 8dbd9e392a96
My application was running successfully, but when I'm trying to open I've this message
This site can’t be reached
This is my list of images :
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
blog latest b9c52b9f2999 About an hour ago 143MB
openjdk 8-jre-alpine 14a48fdee8af 3 days ago 83MB
and my containers list :
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
4dbb68c87813 b9c52b9f2999 "./entrypoint.sh" 27 minutes ago Up 27 minutes 8080/tcp dazzling_shirley
I got this result after running the app using docker image :
----------------------------------------------------------
Application 'blog' is running! Access URLs:
Local: http://localhost:8080
External: http://172.17.0.2:8080
Profile(s): [dev, swagger]
----------------------------------------------------------
I dunno why the app didn't work any help please ?? !

Are you using docker toolbox for windows. Docker toolbox on windows runs docker in a Linux based virtualbox vm. You might have to open the port in the virtual box VM itself. So your host os can access the guest os's port.
See https://www.simplified.guide/virtualbox/port-forwarding

You have to map the docker container port to the host port. The reason is docker container is an isolated environment and it's public ip is same as that of the host machine. You have to ensure that host knows when to redirect requests to the container. So when you map the host port to docker container port, all the requests coming to HOST_IP_ADDRESS:HOST_PORT are redirected to the docker container whose port is mapped to the HOST_PORT.
You do that by using -p flag while using the docker run command as shown below:
docker run -it -p 8080:8080 IMAGE_NAME
Now all the requests coming to localhost:8080 will be directed to application running in container.

How do I connect my docker to remote database?

I want to access mongo db running on url: "xyz" (remote host), and in my spring boot application properties, I have mentioned the mongodb url to "xyz".
Now when i run this application inside a docker container, it can not connect to remote url, and shows the connection refused error.
How do We access the remote database from inside a container ?
Below is my DockerFile
FROM openjdk:8-jdk-alpine
RUN apk add --no-cache bash
RUN apk add --no-cache curl
EXPOSE 8090
COPY target/<jar file> /application.jar
RUN mkdir /logs
RUN /bin/sh -c "apk add --no-cache bash"
ENTRYPOINT ["/usr/bin/java"]
CMD ["-DLOG_DIR=/logs", "-DLOG_FILE=application.log", "-jar", "-Dspring.profiles.active=local", "-Xmx1g", "/application.jar", "&"]
My Application.properties:
spring.data.mongodb.uri = <mongodb-url>
I build my docker image as:
docker build -t app:app .
I run the docker image as:
docker run -d <imageId>

Following command gets the job done.
docker run --net=host <imageId>
Be careful with this command because --net=host makes the container share network with the host. The network of the container will no longer be isolated.