How addamstj/simple-java-maven-app works
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 Maven POM · Jenkinsfile Jenkinsfile · README.md README · AppTest.java AppTest
Components 10
Application
Main Java source and its unit tests.
Build
Maven build descriptor and test reporting.
- Maven POM · Central Maven build configuration.
pom.xml - JUnit XML · Machine-readable test output consumed by Jenkins.
CI Pipeline
Jenkins pipeline definitions and delivery step.
- Jenkinsfile · Primary Jenkins pipeline definition.
jenkins/Jenkinsfile - Test pipeline · Alternate Jenkins pipeline for tutorial validation.
test.jenkinsfile - Deliver script · Pipeline delivery-stage script.
jenkins/scripts/deliver.sh
Repo Hygiene
Source control support files.
- README · Tutorial and workflow notes.
README.md - .gitignore · Ignores generated and local files.
.gitignore - .gitattributes · Controls repository-level file attributes.
.gitattributes
Connections 14
- 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.