datetimeformatter: DateTimeFormatter cheat sheet module (pattern letters incl. the four hour letters, yyyy vs YYYY week-year bug and WeekFields, en_IN locales and the U+202F AM/PM trap with parseLenient fix, SMART/STRICT/LENIENT parsing, ISO constants, SimpleDateFormat thread safety), 18 contract tests

Co-Authored-By: Claude Sonnet 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_017ic4b3fvyFpxThdRxcozLx

datetimeformatter/scripts/run-all.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+# Regenerates every file in output/. 07 (threads) drifts between runs: the counts are indicative.
+set -euo pipefail
+cd "$(dirname "$0")/.."
+mvn -q -B compile
+mkdir -p output
+run() { java -Dstdout.encoding=UTF-8 -cp target/classes "com.ankurm.datetimeformatter.$1" 2>&1 | grep -v '^Picked up JAVA_TOOL_OPTIONS' > "output/$2.txt"; }
+run PatternLettersDemo 01-pattern-letters
+run WeekYearBugDemo    02-week-year-bug
+run LocaleDemo         03-locales
+run ParsingDemo        04-parsing
+run IsoFormatsDemo     05-iso-formats
+run ErrorsDemo         06-errors
+run ThreadSafetyDemo   07-thread-safety
+mvn -B test 2>&1 | grep -E 'Tests run|BUILD|ERROR|FAIL' | grep -v 'Picked up' > output/08-tests.txt
+echo "regenerated:"; ls output

datetimeformatter/scripts/run.sh

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+#!/usr/bin/env bash
+# Run one demo: scripts/run.sh WeekYearBugDemo
+set -euo pipefail
+cd "$(dirname "$0")/.."
+mvn -q -B compile
+java -Dstdout.encoding=UTF-8 -cp target/classes "com.ankurm.datetimeformatter.${1:?demo class name}"