The snippet library.

JavaEncoding & structured values

Encode a form query parameter ↗

Java: URLEncoder uses application/x-www-form-urlencoded rules, including plus signs for spaces.

Java✓ Tested

JavaEncoding & structured values

Encode and decode Base64 bytes ↗

Java: Convert through UTF-8 explicitly before and after Base64 encoding.

Java✓ Tested

JavaGetting Started

Explain a calculation with a comment ↗

Java: Keep the code executable while documenting why a fixed input is used.

Java✓ Tested

JavaText validation & formatting

Extract successive regex matches ↗

Java: Use a Matcher loop to find all unsigned integer tokens in Java text.

Java✓ Tested

JavaText validation & formatting

Extract text between known positions ↗

Java: Java substring uses a start-inclusive, end-exclusive range of UTF-16 indices.

Java✓ Tested

JavaCollections

Filter even numbers ↗

Use a Java stream to collect only even values.

Java✓ Tested

JavaQueues & collection operations

Find set members missing from another set ↗

Java: Use removeAll on a copy to calculate a set difference.

Java✓ Tested

JavaQueues & collection operations

Find shared set members ↗

Java: Copy a set before retainAll when the original must remain unchanged.

Java✓ Tested

JavaStream transformations

Find the first matching stream value ↗

Java: Use findFirst and an explicit default for an empty result.

Java✓ Tested

JavaPrecise numeric calculations

Find the greatest common divisor ↗

Java: BigInteger.gcd calculates an exact nonnegative common divisor.

Java✓ Tested

JavaDates & time zones

Find the last day of a month ↗

Java: Use YearMonth so leap years and month lengths are handled by the calendar library.

Java✓ Tested

JavaDates & time zones

Find the next chosen weekday ↗

Java: TemporalAdjusters.next excludes the starting day even if it already has that weekday.

Java✓ Tested