Package java.util

Class Objects

java.lang.Object

java.util.Objects

public final class Objects
extends Object

Utility methods for objects.

Since:

1.7

Method Summary

Modifier and Type	Method	Description
static <T> int	compare(T a, T b, Comparator<? super T> c)	Returns 0 if a == b, or c.compare(a, b) otherwise.
static boolean	deepEquals(Object a, Object b)	Returns true if both arguments are null, the result of Arrays.equals(byte[], byte[]) if both arguments are primitive arrays, the result of Arrays.deepEquals(java.lang.Object[], java.lang.Object[]) if both arguments are arrays of reference types, and the result of equals(java.lang.Object, java.lang.Object) otherwise.
static boolean	equals(Object a, Object b)	Null-safe equivalent of a.equals(b).
static int	hash(Object... values)	Convenience wrapper for Arrays.hashCode(boolean[]), adding varargs.
static int	hashCode(Object o)	Returns 0 for null or o.hashCode().
static <T> T	requireNonNull(T o)	Returns o if non-null, or throws NullPointerException.
static <T> T	requireNonNull(T o, String message)	Returns o if non-null, or throws NullPointerException with the given detail message.
static String	toString(Object o)	Returns "null" for null or o.toString().
static String	toString(Object o, String nullString)	Returns nullString for null or o.toString().

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

compare

public static <T> int compare(T a,
                              T b,
                              Comparator<? super T> c)

Returns 0 if a == b, or c.compare(a, b) otherwise. That is, this makes c null-safe.

deepEquals

public static boolean deepEquals(Object a,
                                 Object b)

Returns true if both arguments are null, the result of Arrays.equals(byte[], byte[]) if both arguments are primitive arrays, the result of Arrays.deepEquals(java.lang.Object[], java.lang.Object[]) if both arguments are arrays of reference types, and the result of equals(java.lang.Object, java.lang.Object) otherwise.

equals

public static boolean equals(Object a,
                             Object b)

Null-safe equivalent of a.equals(b).

hash

public static int hash(Object... values)

Convenience wrapper for Arrays.hashCode(boolean[]), adding varargs. This can be used to compute a hash code for an object's fields as follows: Objects.hash(a, b, c).

hashCode

public static int hashCode(Object o)

Returns 0 for null or o.hashCode().

requireNonNull

public static <T> T requireNonNull(T o)

Returns o if non-null, or throws NullPointerException.

requireNonNull

public static <T> T requireNonNull(T o,
                                   String message)

Returns o if non-null, or throws NullPointerException with the given detail message.

toString

public static String toString(Object o)

Returns "null" for null or o.toString().

toString

public static String toString(Object o,
                              String nullString)

Returns nullString for null or o.toString().