org.cyclos.utils

Class ObjectHelper

java.lang.Object

org.cyclos.utils.ObjectHelper

public class ObjectHelper
extends java.lang.Object

Helper class for objects

Author:

luis

Constructor Summary

Constructors

Constructor and Description
ObjectHelper()

Method Summary

Modifier and Type	Method and Description
static boolean	areAllNulls(java.lang.Object... elements) Returns true if all elements are null.
static <T> T	coalesce(T... values) Returns the first non-null value
static <T extends java.lang.Comparable<T>> int	compare(T o1, T o2) Compares 2 Comparables, handling nulls
static <S extends Bean,T extends Bean> void	copyProperties(S source, T target) It copies from source to target (apply a bean over another bean) traversing all source's properties. If a property is not found in the target bean or has a different type then it's ignored.
static <T> T	defaultValue(T object, T whenNull) Returns the second parameter when the first is null
static boolean	equalsOrBothNull(java.lang.Object first, java.lang.Object second) Returns true when either both objects are non null and equals or both null
static <T extends Bean> java.util.List<T>	getHierarchyPath(T bean, Property<T,T> parentProperty) Returns a list with the path from the hierarchy root up to the given object, having the given parent property to resolve an object's parent.
static <T extends Bean> int	getLevel(T bean, Property<T,T> parentProperty) Returns the level of a given hierarchical bean.
static int	hashCode(java.lang.Object object) Returns the hashCode of the given object, handling nulls (-1 if null)
static <T> T	ifType(java.lang.Object object, java.lang.Class<T> expectedType) Returns the argument if it is an instance of the given class, otherwise null
static boolean	isEmpty(java.lang.Object object) Returns whether the given object is null or an empty string, collection, map or array
static <T extends Bean> boolean	isEmpty(T bean, Property<?,? super T>... properties)
static boolean	isNotEmpty(java.lang.Object object) Negated value of isEmpty(Object)
static boolean	isNotOneOf(java.lang.Object element, java.lang.Object... objects) Returns true if element is not one of the given objects.
static boolean	isOneOf(java.lang.Object element, java.lang.Object... objects) Returns true if element is one of the objects If element or objects are null it returns false;
static void	requireOneOf(java.lang.Object element, java.lang.Object... objects)
static void	requireOneOf(java.util.function.Supplier<java.lang.String> errorMessageSupplier, java.lang.Object element, java.lang.Object... objects) Checks if element is one of the objects

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectHelper

public ObjectHelper()

Method Detail

areAllNulls

public static boolean areAllNulls(java.lang.Object... elements)

Returns true if all elements are null. If elements is empty or null then returns true.

coalesce

@SafeVarargs
public static <T> T coalesce(T... values)

Returns the first non-null value

compare

public static <T extends java.lang.Comparable<T>> int compare(T o1,
                                                              T o2)

Compares 2 Comparables, handling nulls

copyProperties

public static <S extends Bean,T extends Bean> void copyProperties(S source,
                                                                  T target)

It copies from source to target (apply a bean over another bean) traversing all source's properties.
If a property is not found in the target bean or has a different type then it's ignored.

Throws:

java.lang.IllegalArgumentException - if source, target or both are null.

defaultValue

public static <T> T defaultValue(T object,
                                 T whenNull)

Returns the second parameter when the first is null

equalsOrBothNull

public static boolean equalsOrBothNull(java.lang.Object first,
                                       java.lang.Object second)

Returns true when either both objects are non null and equals or both null

getHierarchyPath

public static <T extends Bean> java.util.List<T> getHierarchyPath(T bean,
                                                                  Property<T,T> parentProperty)

Returns a list with the path from the hierarchy root up to the given object, having the given parent property to resolve an object's parent. For example, if the given object is A1.1.1, the result is [A, A1, A1.1, A1.1.1]

getLevel

public static <T extends Bean> int getLevel(T bean,
                                            Property<T,T> parentProperty)

Returns the level of a given hierarchical bean. The given property needs to resolve the parent bean. Objects with no parent have level 1

hashCode

public static int hashCode(java.lang.Object object)

Returns the hashCode of the given object, handling nulls (-1 if null)

ifType

public static <T> T ifType(java.lang.Object object,
                           java.lang.Class<T> expectedType)

Returns the argument if it is an instance of the given class, otherwise null

isEmpty

public static boolean isEmpty(java.lang.Object object)

Returns whether the given object is null or an empty string, collection, map or array

isEmpty

@SafeVarargs
public static <T extends Bean> boolean isEmpty(T bean,
                                                            Property<?,? super T>... properties)

Parameters:

properties - list of Properties to be checked for empty/null

Returns:

true if observable is null or all of the specified properties are null or empty (see isEmpty(Object)).

isNotEmpty

public static boolean isNotEmpty(java.lang.Object object)

Negated value of isEmpty(Object)

isNotOneOf

public static boolean isNotOneOf(java.lang.Object element,
                                 java.lang.Object... objects)

Returns true if element is not one of the given objects. If element or objects are null it returns false;

isOneOf

public static boolean isOneOf(java.lang.Object element,
                              java.lang.Object... objects)

Returns true if element is one of the objects If element or objects are null it returns false;

requireOneOf

public static void requireOneOf(java.lang.Object element,
                                java.lang.Object... objects)
                         throws java.lang.IllegalArgumentException

Throws:

java.lang.IllegalArgumentException

requireOneOf

public static void requireOneOf(java.util.function.Supplier<java.lang.String> errorMessageSupplier,
                                java.lang.Object element,
                                java.lang.Object... objects)
                         throws java.lang.IllegalArgumentException

Checks if element is one of the objects

Parameters:

errorMessageSupplier - (Optional) Supplier to get the message in case of error

Throws:

java.lang.IllegalArgumentException - if element is not one of the given objects.