Aries' Blog

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Debug spring-boot app with IntelliJ IDEA community

In intelliJ IDEA, if you debug a spring boot app by right-clicking the “main” class (e.g. and select “Debug”, ClassNotFoundException may happen. As suggested on stackoverflow, we should use maven goal spring-boot:run to debug spring boot app. Also we should disable maven “forkmode”, otherwise breakpoint won’t work (I think we could use remote debugging with forkmode but haven’t tried).

Setup maven debug with “spring-boot:run” goal

  1. In IntelliJ menu, select Run -> Edit Configurations
  2. Click the “+” sign to Add New Configuration, select Maven in the dropdown
  3. Use spring-boot:run -Dfork=false as the Command line
  4. Click OK to save the configuration and debug as usual

Option 2 – Disable forkmode in pom.xml

  1. In pom.xml, add property and set it to false
  2. Sample pom.xml snippet
        <!-- For using breakpoint in Debug mode -->
        <!-- Other Properties -->

Install Docker on Ubuntu

There are 2 ways to install Docker engine on Ubuntu, one is easy but the version not as updated. The other one is more complex but is the official way in

1. Easy Way (For older docker version)

Note the package name

sudo apt-get install

2. Hard Way (For latest docker version)

Follow this guide.

  1. Uninstall old versions
    sudo apt-get remove docker docker-engine containerd runc
  2. Setup apt-repository for docker
  3. Install Docker engine
    sudo apt-get update
    sudo apt-get install docker-ce docker-ce-cli
  4. Verify that Docker engine is installed correctly
    sudo docker run hello-world

Bonus – Install docker-compose

Follow this docker-compose guide.

  1. Download current stable release of Docker Compose
    sudo curl -L "$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
  2. Apply executable permissions to the binary
    sudo chmod +x /usr/local/bin/docker-compose
  3. Test installation
    docker-compose --version