Advent of Code solutions in Java

Connect your AoC account

Copy .env.dist to .env and set your Advent of Code session cookie value in SESSION_TOKEN (after logging in to AoC). This enables the CLI to download inputs and validate answers. Test runs and stdin mode do not require network access.

CLI usage

Two scripts are provided at the repository root:

• ./solve — runs the CLI normally
• ./debug — runs the CLI in Quarkus dev mode with the JVM suspended, waiting for a debugger to attach (port 5005)

Both scripts accept the same parameters shown below; debug only changes how the app starts (for debugging).

Common examples

# 1) Run a single day with your AoC input
./solve -y 2023 -d 1

# 2) Run a single day using built‑in test data (no AoC account needed)
./solve -y 2022 -d 13 -t

# 3) Run an entire year with your AoC input
./solve -y 2021

Tip: You can also provide input via stdin for a single day:

echo "<your input>" | ./solve -y 2020 -d 10 -i

Parameters for solve and debug

Below are the supported parameters. All are optional; omit --year and --day to run all released events and all days (1–25).

• Year (-y, --year)

  • Type: integer
  • Required: no
  • Default: all released years (2015..current year; excludes current year if it’s not December)
  • Purpose: Select which event year(s) to run
  • Example: ./solve -y 2023

• Day (-d, --day)

  • Type: integer (1..25)
  • Required: no
  • Default: all days (1..25)
  • Purpose: Select which day(s) to run; if year is omitted, runs that day across all released years
  • Example: ./solve -d 5

• Test mode (-t, --test)

  • Type: flag (boolean)
  • Required: no
  • Default: false
  • Purpose: Run built-in test cases instead of your AoC input
  • Example: ./solve -y 2022 -d 13 -t

• Validate (-v, --validate)

  • Type: flag (boolean)
  • Required: no
  • Default: false
  • Purpose: Validate answers of already completed puzzles using AoC
  • Example: ./solve -y 2021 -d 12 -v

• Overwrite cache (-c, --overwrite-cache)

  • Type: flag (boolean)
  • Required: no
  • Default: false
  • Purpose: Ignore local cache and re-download AoC input and answers
  • Example: ./solve -y 2019 -c

• Read input from stdin (-i, --input-from-stdin)

  • Type: flag (boolean)
  • Required: no (only valid when a single year and single day are specified)
  • Default: false
  • Purpose: Provide puzzle input via stdin; useful for ad-hoc runs or CI
  • Example: echo "..." | ./solve -y 2020 -d 10 -i

Debugging

Use the ./debug script with the same parameters as ./solve:

./debug -y 2023 -d 1

Then attach your IDE’s Remote JVM Debug to localhost:5005.

Running tests on the API

./gradlew test

Scaffolding a solution

Generate a solution class skeleton for a specific year and day:

./scaffold 2023 1

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This repo follows the automation guidelines on the /r/adventofcode community wiki: https://www.reddit.com/r/adventofcode/wiki/faqs/automation

• Once inputs are downloaded, they are cached locally
• If you suspect your input is corrupted, you can execute the solution without a cache by adding -c
• The User-Agent header in com.vuryss.aoc.client.NativeJavaAdventOfCodeClient is set to the repository maintainer