Package org.springframework.util

Class ObjectUtils

java.lang.Object

org.springframework.util.ObjectUtils

public abstract class ObjectUtils
extends Object

Miscellaneous object utility methods.

Mainly for internal use within the framework.

Thanks to Alex Ruiz for contributing several enhancements to this class!

Since:

19.03.2004

Author:

Juergen Hoeller, Keith Donald, Rod Johnson, Rob Harrop, Chris Beams, Sam Brannen

See Also:

• ClassUtils
• CollectionUtils
• StringUtils

Constructor Summary

Constructors

Constructor	Description
ObjectUtils()

Method Summary

Modifier and Type	Method	Description
static <A, O extends A> A[]	addObjectToArray(A[] array, O obj)	Append the given object to the given array, returning a new array consisting of the input array contents plus the given object.
static <A, O extends A> A[]	addObjectToArray(A[] array, O obj, int position)	Add the given object to the given array at the specified position, returning a new array consisting of the input array contents plus the given object.
static <E extends Enum<?>> E	caseInsensitiveValueOf(E[] enumValues, String constant)	Case insensitive alternative to Enum.valueOf(Class, String).
static boolean	containsConstant(Enum<?>[] enumValues, String constant)	Check whether the given array of enum constants contains a constant with the given name, ignoring case when determining a match.
static boolean	containsConstant(Enum<?>[] enumValues, String constant, boolean caseSensitive)	Check whether the given array of enum constants contains a constant with the given name.
static boolean	containsElement(Object[] array, Object element)	Check whether the given array contains the given element.
static String	getDisplayString(Object obj)	Return a content-based String representation if obj is not null; otherwise returns an empty String.
static String	getIdentityHexString(Object obj)	Return a hex String form of an object's identity hash code.
static String	identityToString(Object obj)	Return a String representation of an object's overall identity.
static boolean	isArray(Object obj)	Determine whether the given object is an array: either an Object array or a primitive array.
static boolean	isCheckedException(Throwable ex)	Return whether the given throwable is a checked exception: that is, neither a RuntimeException nor an Error.
static boolean	isCompatibleWithThrowsClause(Throwable ex, Class<?>... declaredExceptions)	Check whether the given exception is compatible with the specified exception types, as declared in a throws clause.
static boolean	isEmpty(Object obj)	Determine whether the given object is empty.
static boolean	isEmpty(Object[] array)	Determine whether the given array is empty: i.e.
static String	nullSafeClassName(Object obj)	Determine the class name for the given object.
static String	nullSafeConciseToString(Object obj)	Generate a null-safe, concise string representation of the supplied object as described below.
static boolean	nullSafeEquals(Object o1, Object o2)	Determine if the given objects are equal, returning true if both are null or false if only one is null.
static int	nullSafeHash(Object... elements)	Return a hash code for the given elements, delegating to nullSafeHashCode(Object) for each element.
static int	nullSafeHashCode(boolean[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(boolean[])
static int	nullSafeHashCode(byte[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(byte[])
static int	nullSafeHashCode(char[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(char[])
static int	nullSafeHashCode(double[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(double[])
static int	nullSafeHashCode(float[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(float[])
static int	nullSafeHashCode(int[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(int[])
static int	nullSafeHashCode(long[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(long[])
static int	nullSafeHashCode(short[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(short[])
static int	nullSafeHashCode(Object obj)	Return a hash code for the given object; typically the value of Object#hashCode()}.
static int	nullSafeHashCode(Object[] array)	Deprecated. as of 6.1 in favor of Arrays.hashCode(Object[])
static String	nullSafeToString(boolean[] array)	Return a String representation of the contents of the specified array.
static String	nullSafeToString(byte[] array)	Return a String representation of the contents of the specified array.
static String	nullSafeToString(char[] array)	Return a String representation of the contents of the specified array.
static String	nullSafeToString(double[] array)	Return a String representation of the contents of the specified array.
static String	nullSafeToString(float[] array)	Return a String representation of the contents of the specified array.
static String	nullSafeToString(int[] array)	Return a String representation of the contents of the specified array.
static String	nullSafeToString(long[] array)	Return a String representation of the contents of the specified array.
static String	nullSafeToString(short[] array)	Return a String representation of the contents of the specified array.
static String	nullSafeToString(Object obj)	Return a String representation of the specified Object.
static String	nullSafeToString(Object[] array)	Return a String representation of the contents of the specified array.
static Object[]	toObjectArray(Object source)	Convert the given array (which may be a primitive array) to an object array (if necessary of primitive wrapper objects).
static Object	unwrapOptional(Object obj)	Unwrap the given object which is potentially a Optional.

Methods inherited from class java.lang.Object

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

Constructor Details

ObjectUtils

public ObjectUtils()

Method Details

isCheckedException

public static boolean isCheckedException(Throwable ex)

Return whether the given throwable is a checked exception: that is, neither a RuntimeException nor an Error.

Parameters:

ex - the throwable to check

Returns:

whether the throwable is a checked exception

See Also:

• Exception
• RuntimeException
• Error

isCompatibleWithThrowsClause

public static boolean isCompatibleWithThrowsClause(Throwable ex,
 @Nullable
 Class<?>... declaredExceptions)

Check whether the given exception is compatible with the specified exception types, as declared in a throws clause.

Parameters:

ex - the exception to check

declaredExceptions - the exception types declared in the throws clause

Returns:

whether the given exception is compatible

isArray

public static boolean isArray(@Nullable
 Object obj)

Determine whether the given object is an array: either an Object array or a primitive array.

Parameters:

obj - the object to check

isEmpty

public static boolean isEmpty(@Nullable
 Object[] array)

Determine whether the given array is empty: i.e. null or of zero length.

Parameters:

array - the array to check

See Also:

• isEmpty(Object)

isEmpty

public static boolean isEmpty(@Nullable
 Object obj)

Determine whether the given object is empty.

This method supports the following object types.

• Optional: considered empty if not Optional.isPresent()
• Array: considered empty if its length is zero
• CharSequence: considered empty if its length is zero
• Collection: delegates to Collection.isEmpty()