Phase 2: Generate Upgrade Plan

Load this file when executing Phase 2. Refer back to upgrade-success-criteria and upgrade-strategy for success criteria and strategy, and ../rules/troubleshooting.md when failures occur.

1. Initialize

1. Update plan.md: replace all remaining placeholders
2. Extract user-specified guidelines from prompt into "Guidelines" section (bulleted list; leave empty if none)

2. Environment Analysis

1. Read HTML comments in "Available Tools" section of plan.md to understand rules and expected format
2. Record discovered JDK versions and paths
3. Detect wrapper presence; if wrapper exists, read wrapper properties to determine build tool version
4. Check build tool version compatibility with JDK — flag incompatible versions for upgrade

3. Dependency Analysis

1. Read HTML comments in "Technology Stack" and "Derived Upgrades" sections of plan.md to understand rules and expected format
2. Identify core tech stack across ALL modules (direct deps + upgrade-critical deps)
3. Include build tool (Maven/Gradle) and build plugins (maven-compiler-plugin, maven-surefire-plugin, etc.) in the technology stack analysis
4. Flag EOL dependencies (high priority for upgrade)
5. Consult the Migration Guidelines for package mappings and migration guides
6. Populate "Technology Stack" and "Derived Upgrades"

4. Upgrade Path Design

1. Read HTML comments in "Key Challenges" and "Upgrade Steps" sections of plan.md to understand rules and expected format
2. For incompatible deps, prefer: Replacement > Adaptation > Rewrite
3. Finalize "Available Tools" section based on the planned step sequence
4. Design step sequence:

• Step 1 (MANDATORY): Setup Baseline — run compile/test with current JDK, document results
• Steps 2-N: Upgrade steps — dependency order, high-risk early, isolated breaking changes. Compilation must pass (both main and test code); test failures documented for Final Validation.
• Final step (MANDATORY): Final Validation — verify all goals met, all TODOs resolved, achieve Upgrade Success Criteria through iterative test & fix loop.

1. Identify high-risk areas for "Key Challenges" section
2. Write steps following format in plan.md

5. Plan Review

1. Verify all placeholders filled in plan.md, check for missing coverage/infeasibility/limitations
2. Revise plan as needed for completeness and feasibility; document unfixable limitations in "Plan Review" section
3. Ensure all sections of plan.md are fully populated (per Template compliance rule) and all HTML comments removed

After plan generation, proceed directly to execution — create .github/java-upgrade/{RUN_ID}/progress.md from the Progress Template, replace placeholders, and begin execution. Log the migration plan, then proceed without pausing for confirmation.