codeanalyzer-java: L1 v2 tree emission

[sinha108]

Plan (optional)

Design spec: https://github.com/codellm-devkit/codeanalyzer-java/blob/main/docs/design/specs/schema-v2-l3-l4-design.md

Problem

The analyzer emits the legacy v1 tree (combinedJsonObject.add("symbol_table", …), CodeAnalyzer.java) with JType is_* booleans, per-callable code, and flat start_line/end_line. Canonical schema v2 requires an additive CPG tree: an envelope, per-module source blob, byte-offset spans, can:// ids, structured decorators, nested metrics/refs, and body call nodes.

Scope boundary

L1 tree emission only — no call_graph edges (that is the L2 issue), no dataflow. Keep the JavaParser compute guts; rewrite only the emission layer. The v1 emitter is kept behind a flag as a superset oracle during transition. Pure structural emission — no analysis-engine changes.

Goals

• Envelope {schema_version:"2.0.0", language:"java", max_level, analyzer{name,version}, application{id,kind,symbol_table}}
• module{id, kind:"module", span, source, package, imports, types, functions, content_hash}; byte offsets on every span
• type.kind ∈ {class,interface,enum,record,annotation} + nesting{parent?,is_local?} (D4); base_types/interfaces; structured decorators:[{name,args,span}] (D2)
• callable{id, kind, signature, span, parameters, return_type, error_channel, modifiers, decorators, metrics{cyclomatic}, refs{types,fields}, body{}} (D1, D3); thrown_exceptions → error_channel
• body call nodes {kind:"call", span, callee:null, arguments:[local-id]} (callee backfilled at L2)
• can://java/<app>/<file>/<type>/<sig> id construction from signatureOf() (D8)
• v1 emitter behind a flag (superset oracle)

Caveats and known risks

• Span byte offsets depend on JavaParser token positions; degrade gracefully where absent.
• symbol_table keys must be relative (never absolute or ..-prefixed).
• Callable kinds: method, constructor, initializer (static/instance init blocks), lambda; is_variadic for varargs.

Definition of done

• L1 gate: output validates against the SDK Application; symbol_table non-empty, relative keys; a known module has source and the get_method_body slice = module.source[span.bytes]; call nodes carry callee:null; can:// ids stable across two runs; re-run reuses cache.
• Monotonicity holds for L1; determinism -j N byte-identical to -j 1.

[sinha108]

L1 conformance oracle (decided during design, before implementation):

Validate emitted analysis.json against an in-repo JSON Schema at src/test/resources/schema/analysis.v2.schema.json (encoding the canonical v2 Application shape), plus round-trip the JSON back through the v2 Lombok models for self-consistency.

• Self-contained — no dependency on the downstream python-sdk v2 Java models (#310); tighten to those models when #310 lands.
• Rationale: the SDK v2 Java models don't exist yet, so the L1 gate can't validate against them; the JSON Schema is the interim oracle for the keystone shape.
• Test infra present: JUnit 5 + Gson; a JSON-schema validator dep (e.g. com.networknt:json-schema-validator) to be added as testImplementation.