REFERENCE-maven.md

Reference build: Maven

Supporting context for migrating from Maven. The migration process itself lives in SKILL.md; this file only covers what is unique to Maven as the reference build.

Status: early — argv-floor only. Treat output as exploratory.

Detecting it

A pom.xml at the repo root.

Scope traps

Not yet supported:

• Coordinate-identity deps (group:artifact:version, scope) — not extracted.
• Java flag canonicalization.

The C/C++ any2bazel.json levers and the fix table in SKILL.md don't apply to Java source sets.

Extracting the reference model

Maven has no action graph; the reference is the forked javac argument file.

mvn clean compile -Dmaven.compiler.fork=true          # writes <module>/target/*arguments
python3 "$SKILL_DIR/scripts/extract_maven.py" <module_dir> <repo_root> model.maven.json

Extracting the Bazel action graph

Use the Javac mnemonic in place of the C/C++ mnemonic set:

bazel aquery 'mnemonic("Javac", //...)' \
    --features=-compiler_param_file --features=-linker_param_file \
    --output=jsonproto > aquery.json

Comparison and diff kinds

Java compiles a whole source set at once, so it's compared as a project-wide union of .java sources (grouping/naming agnostic), analogous to how libraries are compared.

kind	meaning
missing_java_src	a .java compiled by Maven but not Bazel — add it to a java_library's srcs
extra_java_src	a .java compiled by Bazel but not Maven