# addamstj/simple-java-maven-app architecture

> Architecture diagram of the GitHub repository addamstj/simple-java-maven-app, generated by GitDiagram from its file tree, README and a sample of source files (last updated 2026-06-29). It is an AI-made overview: check details against the source.

- Interactive diagram: https://gitdiagram.com/addamstj/simple-java-maven-app
- Repository: https://github.com/addamstj/simple-java-maven-app

## Overview

1. **Repository purpose**
   - This is a minimal **Java/Maven application** used in a Jenkins tutorial.
   - The runtime behavior is intentionally simple: the app prints **“Hello world!”**.

2. **Core application boundary**
   - The main product code lives under `src/main/java/com/mycompany/app/App.java`.
   - This is the only application source module visible in the tree, so the functional scope is a single executable entry point rather than a multi-module system.

3. **Test boundary**
   - Tests live separately under `src/test/java/com/mycompany/app/AppTest.java`.
   - This clean separation shows the standard Maven structure: production code and test code are isolated, with tests validating the app’s expected output/behavior.

4. **Build system**
   - `pom.xml` is the central build descriptor.
   - Maven is responsible for compiling the Java source, running unit tests, and producing test artifacts; it is the main orchestration layer for local and CI builds.

5. **Test reporting**
   - The README states that test results are saved as a **JUnit XML report**.
   - That means the test phase is not just pass/fail locally; it produces machine-readable output that Jenkins can ingest for CI reporting.

6. **CI/CD automation**
   - The `jenkins/` directory contains Jenkins pipeline assets.
   - `jenkins/Jenkinsfile` represents the pipeline definition used by Jenkins, while `test.jenkinsfile` suggests an alternate or tutorial-specific pipeline configuration for validation.

7. **Delivery/deploy stage**
   - `jenkins/scripts/deliver.sh` is the shell script executed during the pipeline’s “Deliver” stage.
   - Architecturally, this is the handoff point from build/test automation to whatever delivery action the tutorial demonstrates, even though the repo itself is minimal.

8. **End-to-end data flow**
   - Source changes start in `src/main/java`.
   - Maven compiles and tests them via `pom.xml`.
   - Test execution emits JUnit XML.
   - Jenkins consumes the pipeline definition, runs the build, reads test results, and invokes the delivery script as part of the CI flow.

9. **Technology boundaries**
   - The project is centered on **Java**, **Maven**, **JUnit**, and **Jenkins**.
   - These tools define the architecture more than any application framework: this is a build-and-delivery demonstration repo, not a layered service with databases, APIs, or message brokers.

10. **Supporting files**
   - `.gitignore` and `.gitattributes` support repository hygiene and source control behavior.
   - They do not contribute to runtime architecture, but they help keep the build/test workflow stable and predictable.

Main entry points: [`pom.xml`](https://github.com/addamstj/simple-java-maven-app/blob/master/pom.xml) (Maven POM), [`jenkins/Jenkinsfile`](https://github.com/addamstj/simple-java-maven-app/tree/master/jenkins/Jenkinsfile) (Jenkinsfile), [`README.md`](https://github.com/addamstj/simple-java-maven-app/blob/master/README.md) (README), [`src/test/java/com/mycompany/app/AppTest.java`](https://github.com/addamstj/simple-java-maven-app/blob/master/src/test/java/com/mycompany/app/AppTest.java) (AppTest)

## Diagram (Mermaid)

```mermaid
flowchart TD

subgraph group_g_app["Application"]
  node_n_app["App<br/>java entrypoint<br/>[App.java]"]
  node_n_test["AppTest<br/>unit test<br/>[AppTest.java]"]
end

subgraph group_g_build["Build"]
  node_n_pom["Maven POM<br/>build descriptor<br/>[pom.xml]"]
  node_n_junit["JUnit XML<br/>test report"]
end

subgraph group_g_ci["CI Pipeline"]
  node_n_jenkinsfile["Jenkinsfile<br/>pipeline"]
  node_n_test_jenkinsfile["Test pipeline<br/>pipeline variant<br/>[test.jenkinsfile]"]
  node_n_deliver["Deliver script<br/>shell step<br/>[deliver.sh]"]
end

subgraph group_g_repo["Repo Hygiene"]
  node_n_readme["README<br/>doc<br/>[README.md]"]
  node_n_gitignore[".gitignore<br/>repo config<br/>[.gitignore]"]
  node_n_gitattributes[".gitattributes<br/>repo config<br/>[.gitattributes]"]
end

node_n_readme -.->|"documents build"| node_n_pom
node_n_pom -->|"compiles"| node_n_app
node_n_pom -->|"runs tests"| node_n_test
node_n_test -->|"verifies behavior"| node_n_app
node_n_test -->|"emits"| node_n_junit
node_n_jenkinsfile -->|"drives build"| node_n_pom
node_n_jenkinsfile -->|"publishes"| node_n_junit
node_n_jenkinsfile -->|"invokes"| node_n_deliver
node_n_test_jenkinsfile -.->|"validates build"| node_n_pom
node_n_test_jenkinsfile -.->|"exercises delivery"| node_n_deliver
node_n_readme -.->|"describes CI"| node_n_jenkinsfile
node_n_readme -.->|"mentions reports"| node_n_junit
node_n_gitignore -.->|"supports workflow"| node_n_pom
node_n_gitattributes -.->|"supports workflow"| node_n_pom

click node_n_readme "https://github.com/addamstj/simple-java-maven-app/blob/master/README.md"
click node_n_pom "https://github.com/addamstj/simple-java-maven-app/blob/master/pom.xml"
click node_n_app "https://github.com/addamstj/simple-java-maven-app/blob/master/src/main/java/com/mycompany/app/App.java"
click node_n_test "https://github.com/addamstj/simple-java-maven-app/blob/master/src/test/java/com/mycompany/app/AppTest.java"
click node_n_jenkinsfile "https://github.com/addamstj/simple-java-maven-app/tree/master/jenkins/Jenkinsfile"
click node_n_test_jenkinsfile "https://github.com/addamstj/simple-java-maven-app/blob/master/test.jenkinsfile"
click node_n_deliver "https://github.com/addamstj/simple-java-maven-app/blob/master/jenkins/scripts/deliver.sh"
click node_n_gitignore "https://github.com/addamstj/simple-java-maven-app/blob/master/.gitignore"
click node_n_gitattributes "https://github.com/addamstj/simple-java-maven-app/blob/master/.gitattributes"

classDef toneNeutral fill:#f8fafc,stroke:#334155,stroke-width:1.5px,color:#0f172a
classDef toneBlue fill:#dbeafe,stroke:#2563eb,stroke-width:1.5px,color:#172554
classDef toneAmber fill:#fef3c7,stroke:#d97706,stroke-width:1.5px,color:#78350f
classDef toneMint fill:#dcfce7,stroke:#16a34a,stroke-width:1.5px,color:#14532d
classDef toneRose fill:#ffe4e6,stroke:#e11d48,stroke-width:1.5px,color:#881337
classDef toneIndigo fill:#e0e7ff,stroke:#4f46e5,stroke-width:1.5px,color:#312e81
classDef toneTeal fill:#ccfbf1,stroke:#0f766e,stroke-width:1.5px,color:#134e4a
class node_n_app,node_n_test toneBlue
class node_n_pom,node_n_junit toneAmber
class node_n_jenkinsfile,node_n_test_jenkinsfile,node_n_deliver toneMint
class node_n_readme,node_n_gitignore,node_n_gitattributes toneRose
```

## Components

### Application

Main Java source and its unit tests.

- [App](https://github.com/addamstj/simple-java-maven-app/blob/master/src/main/java/com/mycompany/app/App.java): java entrypoint · Main application that prints Hello world. · `src/main/java/com/mycompany/app/App.java`
- [AppTest](https://github.com/addamstj/simple-java-maven-app/blob/master/src/test/java/com/mycompany/app/AppTest.java): unit test · Validates the application behavior. · `src/test/java/com/mycompany/app/AppTest.java`

### Build

Maven build descriptor and test reporting.

- [Maven POM](https://github.com/addamstj/simple-java-maven-app/blob/master/pom.xml): build descriptor · Central Maven build configuration. · `pom.xml`
- **JUnit XML**: test report · Machine-readable test output consumed by Jenkins.

### CI Pipeline

Jenkins pipeline definitions and delivery step.

- [Jenkinsfile](https://github.com/addamstj/simple-java-maven-app/tree/master/jenkins/Jenkinsfile): pipeline · Primary Jenkins pipeline definition. · `jenkins/Jenkinsfile`
- [Test pipeline](https://github.com/addamstj/simple-java-maven-app/blob/master/test.jenkinsfile): pipeline variant · Alternate Jenkins pipeline for tutorial validation. · `test.jenkinsfile`
- [Deliver script](https://github.com/addamstj/simple-java-maven-app/blob/master/jenkins/scripts/deliver.sh): shell step · Pipeline delivery-stage script. · `jenkins/scripts/deliver.sh`

### Repo Hygiene

Source control support files.

- [README](https://github.com/addamstj/simple-java-maven-app/blob/master/README.md): doc · Tutorial and workflow notes. · `README.md`
- [.gitignore](https://github.com/addamstj/simple-java-maven-app/blob/master/.gitignore): repo config · Ignores generated and local files. · `.gitignore`
- [.gitattributes](https://github.com/addamstj/simple-java-maven-app/blob/master/.gitattributes): repo config · Controls repository-level file attributes. · `.gitattributes`

## Connections

- README → Maven POM: documents build · README explains the Maven workflow and expected output.
- Maven POM → App: compiles · Maven compiles the main Java source.
- Maven POM → AppTest: runs tests · Maven executes the unit test phase.
- AppTest → App: verifies behavior · Tests assert the application output and behavior.
- AppTest → JUnit XML: emits · Test execution produces JUnit XML for CI reporting.
- Jenkinsfile → Maven POM: drives build · Jenkins uses Maven as the build and test orchestrator.
- Jenkinsfile → JUnit XML: publishes · Pipeline collects machine-readable test results.
- Jenkinsfile → Deliver script: invokes · Pipeline reaches the delivery stage via the shell script.
- Test pipeline → Maven POM: validates build · Alternate pipeline also centers on the Maven build.
- Test pipeline → Deliver script: exercises delivery · Tutorial-specific pipeline can include the delivery step.
- README → Jenkinsfile: describes CI · README and tutorial context explain the Jenkins flow.
- README → JUnit XML: mentions reports · README notes JUnit XML as the test artifact.
- .gitignore → Maven POM: supports workflow · Keeps generated files out of version control.
- .gitattributes → Maven POM: supports workflow · Provides repository-level source control behavior.