Hutool 3.9 [portable] · Secure & Instant

Hutool 3.9 is a pivotal version of the popular Hutool Java tool library, marking a significant era in its development where the library focused on modularization and performance. Known for its philosophy of keeping "Java sweet," Hutool serves as a comprehensive "util" package replacement that simplifies complex standard Java APIs into elegant, static methods. The Core Philosophy of Hutool

// Reads all lines from a UTF-8 file. Auto-closes.
List<String> lines = FileUtil.readLines("config/users.txt", "UTF-8");
// Chainable: watch with multiple event types public WatchBuilder on(Path file, WatchEvent.Kind<?>... events) watches.computeIfAbsent(file, k -> new HashSet<>()) .addAll(Arrays.asList(events)); return this;

3. The CollStreamUtil (A Developer Favorite)

One of the most beloved features of 3.9 is the introduction of CollStreamUtil. Java 8 streams are powerful but verbose. CollStreamUtil.toIdentityMap(list, Student::getId) collapses a list into a map in one line, handling key conflicts gracefully. Hutool 3.9

Core (hutool-core): Includes Bean operations, date handling, and various basic utilities. Hutool 3