A real‑world bug caused by incorrect year‑week calculation is explained, then the ISO‑8601 week‑based year definition and Java's LocalDate/WeekFields APIs are introduced to reliably compute the correct year and week for any date.
This article introduces Java 8’s new language features—Lambda expressions, the Stream API, and the modern date‑time classes—explaining their syntax, core concepts, and practical usage through clear examples and code snippets that illustrate how they simplify collection processing and date handling.
This article introduces Java 8's new date‑time API, explains its advantages over the old java.util.Date and SimpleDateFormat, lists the essential classes such as Instant, LocalDate, LocalTime, ZonedDateTime, and provides step‑by‑step code examples for common operations like getting the current date, manipulating specific dates, handling time zones, and formatting.
This article explains why Java needed a new date‑time library, introduces the core concepts of the java.time API such as immutable value classes, domain‑driven design, factory methods, adjusters, periods, durations, time‑zone handling, and non‑ISO calendars, and provides concrete code examples for each feature.
A game server bug caused hundreds of reward emails to be sent on New Year's Day because a copied Java date‑difference function returned incorrect values for cross‑year dates, and the issue was resolved by replacing it with a reliable Java 8 time API implementation.
This tutorial explains why the old java.util.Date and Calendar APIs were problematic, introduces the immutable, thread‑safe Java 8 Date‑Time classes such as LocalDate, LocalTime, LocalDateTime, ZonedDateTime, Period and Duration, shows practical code examples for creation, manipulation, formatting, conversion and compatibility, and lists alternative libraries like ThreeTen‑BP and Joda‑Time.
