java.util · java.base · since Java 1.7

Objects

declaration

public final class Objects

Null-safe static helpers: equality, hashing, null checks with messages. requireNonNull at method entry is idiomatic precondition checking (EJ 49).

Key methods

`static boolean equals(Object a, Object b)`	Null-safe equals — true if both null.
`static int hash(Object... values)`	Composite hash for hashCode() implementations (boxes varargs — fine outside hot paths).
`static <T> T requireNonNull(T obj, String message)`	Throw NPE with context if null — fail fast at the boundary.
`static <T> T requireNonNullElse(T obj, T default)`	Null-coalescing.
`static String toString(Object o, String default)`	Null-safe toString.