Update Java docs from 17 to 21 java version

content/guides/java/containerize.md

@@ -68,7 +68,7 @@ WARNING: The following Docker files already exist in this directory:
 ? Do you want to overwrite them? Yes
 ? What application platform does your project use? Java
 ? What's the relative directory (with a leading .) for your app? ./src
-? What version of Java do you want to use? 17
+? What version of Java do you want to use? 21
 ? What port does your server listen on? 8080
 ```
 
@@ -98,7 +98,7 @@ Create a file named `Dockerfile` with the following contents.
 ################################################################################
 
 # Create a stage for resolving and downloading dependencies.
-FROM eclipse-temurin:17-jdk-jammy as deps
+FROM eclipse-temurin:21-jre-jammy as deps
 
 WORKDIR /build
 
@@ -155,7 +155,7 @@ RUN java -Djarmode=layertools -jar target/app.jar extract --destination target/e
 # most recent version of that tag when you build your Dockerfile.
 # If reproducability is important, consider using a specific digest SHA, like
 # eclipse-temurin@sha256:99cede493dfd88720b610eb8077c8688d3cca50003d76d1d539b0efc8cca72b4.
-FROM eclipse-temurin:17-jre-jammy AS final
+FROM eclipse-temurin:21-jre-jammy AS final
 
 # Create a non-privileged user that the app will run under.
 # See https://docs.docker.com/go/dockerfile-user-best-practices/

content/guides/java/develop.md

@@ -121,7 +121,7 @@ Replace the contents of your Dockerfile with the following.
 ```dockerfile {hl_lines="22-29"}
 # syntax=docker/dockerfile:1
 
-FROM eclipse-temurin:17-jdk-jammy as deps
+FROM eclipse-temurin:21-jdk-jammy as deps
 WORKDIR /build
 COPY --chmod=0755 mvnw mvnw
 COPY .mvn/ .mvn/
@@ -149,7 +149,7 @@ RUN cp -r /build/target/extracted/application/. ./
 ENV JAVA_TOOL_OPTIONS -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=*:8000
 CMD [ "java", "-Dspring.profiles.active=postgres", "org.springframework.boot.loader.launch.JarLauncher" ]
 
-FROM eclipse-temurin:17-jre-jammy AS final
+FROM eclipse-temurin:21-jre-jammy AS final
 ARG UID=10001
 RUN adduser \
     --disabled-password \

content/guides/java/run-tests.md

@@ -25,7 +25,7 @@ Replace the contents of your Dockerfile with the following.
 ```dockerfile {hl_lines="3-19"}
 # syntax=docker/dockerfile:1
 
-FROM eclipse-temurin:17-jdk-jammy as base
+FROM eclipse-temurin:21-jre-jammy as base
 WORKDIR /build
 COPY --chmod=0755 mvnw mvnw
 COPY .mvn/ .mvn/
@@ -64,7 +64,7 @@ RUN cp -r /build/target/extracted/application/. ./
 ENV JAVA_TOOL_OPTIONS="-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=*:8000"
 CMD [ "java", "-Dspring.profiles.active=postgres", "org.springframework.boot.loader.launch.JarLauncher" ]
 
-FROM eclipse-temurin:17-jre-jammy AS final
+FROM eclipse-temurin:21-jre-jammy AS final
 ARG UID=10001
 RUN adduser \
     --disabled-password \

content/language/_index.md

@@ -0,0 +1,58 @@
+---
+description: Language-specific guides overview
+keywords: guides, docker, language, node, java, python, R, go, golang, .net, c++
+title: Language-specific guides overview
+toc_min: 1
+toc_max: 2
+aliases:
+- /guides/walkthroughs/containerize-your-app/
+---
+
+The language-specific guides walk you through the process of:
+* Containerizing language-specific applications
+* Setting up a development environment
+* Configuring a CI/CD pipeline
+* Deploying an application locally using Kubernetes
+
+In addition to the language-specific modules, Docker documentation also provides guidelines to build images and efficiently manage your development environment. For more information, refer to the following topics:
+
+* [Building best practices](../build/building/best-practices.md)
+* [Build images with BuildKit](../build/buildkit/index.md#getting-started)
+* [Build with Docker](../build/guide/_index.md)
+
+## Language-specific guides
+
+Learn how to containerize your applications and start developing using Docker. Choose one of the following languages to get started.
+
+<div class="grid grid-cols-2 md:grid-cols-3 h-auto gap-4">
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/nodejs/"><img class="m-auto rounded" src="/language/images/nodejs.webp" alt="Develop with Node"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/python/"><img class="m-auto rounded" src="/language/images/python.webp" alt="Develop with Python"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/r/"><img class="m-auto rounded" src="/language/images/r.webp" alt="Develop with R"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/java/"><img class="m-auto rounded" src="/language/images/java.webp" alt="Develop with Java"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/golang/"><img class="m-auto rounded" src="/language/images/golang.webp" alt="Develop with Go"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/dotnet/"><img class="m-auto rounded" src="/language/images/c-sharp.webp" alt="Develop with C#"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/cpp/"><img class="m-auto rounded" src="/language/images/cpp.webp" alt="Develop with C++"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/rust/"><img class="m-auto rounded" src="/language/images/rust-logo.webp" alt="Develop with Rust"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/php/"><img class="m-auto rounded" src="/language/images/php-logo.webp" alt="Develop with PHP"></a>
+    </div>
+    <div class="flex items-center flex-1 shadow p-4">
+        <a href="/language/ruby/"><img class="m-auto rounded" src="/language/images/ruby-on-rails.webp" alt="Develop with Ruby"></a>
+    </div>
+</div>

content/language/ruby/_index.md

@@ -0,0 +1,18 @@
+---
+description: Containerize Ruby on Rails apps using Docker
+keywords: Docker, getting started, ruby, language
+title: Ruby on Rails language-specific guide
+toc_min: 1
+toc_max: 2
+---
+
+The Ruby language-specific guide teaches you how to containerize a Ruby on Rails application using Docker. In this guide, you’ll learn how to:
+
+* Containerize and run a Ruby on Rails application
+* Set up a local environment to develop a Ruby on Rails application using containers
+* Configure a CI/CD pipeline for a containerized Ruby on Rails application using GitHub Actions
+* Deploy your containerized Ruby on Rails application locally to Kubernetes to test and debug your deployment
+
+Start by containerizing an existing Ruby on Rails application.
+
+{{< button text="Containerize a Ruby on Rails app" url="containerize.md" >}}

content/language/ruby/configure-ci-cd.md

@@ -0,0 +1,129 @@
+---
+title: Configure CI/CD for your Ruby on Rails application
+keywords: ci/cd, github actions, ruby, flask
+description: Learn how to configure CI/CD using GitHub Actions for your Ruby on Rails application.
+---
+
+## Prerequisites
+
+Complete all the previous sections of this guide, starting with [Containerize a Ruby on Rails application](containerize.md). You must have a [GitHub](https://github.com/signup) account and a [Docker](https://hub.docker.com/signup) account to complete this section.
+
+## Overview
+
+In this section, you'll learn how to set up and use GitHub Actions to build and test your Docker image as well as push it to Docker Hub. You will complete the following steps:
+
+1. Create a new repository on GitHub.
+2. Define the GitHub Actions workflow.
+3. Run the workflow.
+
+## Step one: Create the repository
+
+Create a GitHub repository, configure the Docker Hub credentials, and push your source code.
+
+1. [Create a new repository](https://github.com/new) on GitHub.
+
+2. Open the repository **Settings**, and go to **Secrets and variables** >
+   **Actions**.
+
+3. Create a new **Repository variable** named `DOCKER_USERNAME` and your Docker ID as value.
+
+4. Create a new [Personal Access Token (PAT)](../../security/for-developers/access-tokens.md/#create-an-access-token) for Docker Hub. You can name this token `docker-tutorial`. Make sure access permissions include Read and Write.
+
+5. Add the PAT as a **Repository secret** in your GitHub repository, with the name
+   `DOCKERHUB_TOKEN`.
+
+6. In your local repository on your machine, run the following command to change
+   the origin to the repository you just created. Make sure you change
+   `your-username` to your GitHub username and `your-repository` to the name of
+   the repository you created.
+
+   ```console
+   $ git remote set-url origin https://github.com/your-username/your-repository.git
+   ```
+
+7. Run the following commands to stage, commit, and push your local repository to GitHub.
+
+   ```console
+   $ git add -A
+   $ git commit -m "my commit"
+   $ git push -u origin main
+   ```
+
+## Step two: Set up the workflow
+
+Set up your GitHub Actions workflow for building, testing, and pushing the image
+to Docker Hub.
+
+1. Go to your repository on GitHub and then select the **Actions** tab.
+
+2. Select **set up a workflow yourself**.
+
+   This takes you to a page for creating a new GitHub actions workflow file in
+   your repository, under `.github/workflows/main.yml` by default.
+
+3. In the editor window, copy and paste the following YAML configuration.
+
+   ```yaml
+   name: ci
+
+   on:
+     push:
+       branches:
+         - main
+
+   jobs:
+     build:
+       runs-on: ubuntu-latest
+       steps:
+         -
+           name: Login to Docker Hub
+           uses: docker/login-action@v3
+           with:
+             username: ${{ vars.DOCKER_USERNAME }}
+             password: ${{ secrets.DOCKERHUB_TOKEN }}
+         -
+           name: Set up Docker Buildx
+           uses: docker/setup-buildx-action@v3
+         -
+           name: Build and push
+           uses: docker/build-push-action@v6
+           with:
+             platforms: linux/amd64
+             push: true
+             tags: ${{ vars.DOCKER_USERNAME }}/${{ github.event.repository.name }}:latest
+   ```
+
+   For more information about the YAML syntax for `docker/build-push-action`,
+   refer to the [GitHub Action README](https://github.com/docker/build-push-action/blob/master/README.md).
+
+## Step three: Run the workflow
+
+Save the workflow file and run the job.
+
+1. Select **Commit changes...** and push the changes to the `main` branch.
+
+   After pushing the commit, the workflow starts automatically.
+
+2. Go to the **Actions** tab. It displays the workflow.
+
+   Selecting the workflow shows you the breakdown of all the steps.
+
+3. When the workflow is complete, go to your
+   [repositories on Docker Hub](https://hub.docker.com/repositories).
+
+   If you see the new repository in that list, it means the GitHub Actions
+   successfully pushed the image to Docker Hub.
+
+## Summary
+
+In this section, you learned how to set up a GitHub Actions workflow for your Ruby on Rails application.
+
+Related information:
+ - [Introduction to GitHub Actions](../../build/ci/github-actions/index.md)
+ - [Workflow syntax for GitHub Actions](https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions)
+
+## Next steps
+
+Next, learn how you can locally test and debug your workloads on Kubernetes before deploying.
+
+{{< button text="Test your deployment" url="./deploy.md" >}}