Class Data (1.42.0)

public class Data

Utilities for working with key/value data based on the Key annotation.

Inheritance

Object > Data

Inherited Members

Object.clone()

Object.equals(Object)

Object.finalize()

Object.getClass()

Object.hashCode()

Object.notify()

Object.notifyAll()

Object.toString()

Object.wait()

Object.wait(long)

Object.wait(long,int)

Static Fields

NULL_BIG_DECIMAL

public static final BigDecimal NULL_BIG_DECIMAL

The single instance of the magic null object for a BigDecimal.

Field Value

Type	Description
BigDecimal

NULL_BIG_INTEGER

public static final BigInteger NULL_BIG_INTEGER

The single instance of the magic null object for a BigInteger.

Field Value

Type	Description
BigInteger

NULL_BOOLEAN

public static final Boolean NULL_BOOLEAN

The single instance of the magic null object for a Boolean.

Field Value

Type	Description
Boolean

NULL_BYTE

public static final Byte NULL_BYTE

The single instance of the magic null object for a Byte.

Field Value

Type	Description
Byte

NULL_CHARACTER

public static final Character NULL_CHARACTER

The single instance of the magic null object for a Character.

Field Value

Type	Description
Character

NULL_DATE_TIME

public static final DateTime NULL_DATE_TIME

The single instance of the magic null object for a DateTime.

Field Value

Type	Description
DateTime

NULL_DOUBLE

public static final Double NULL_DOUBLE

The single instance of the magic null object for a Double.

Field Value

Type	Description
Double

NULL_FLOAT

public static final Float NULL_FLOAT

The single instance of the magic null object for a Float.

Field Value

Type	Description
Float

NULL_INTEGER

public static final Integer NULL_INTEGER

The single instance of the magic null object for a Integer.

Field Value

Type	Description
Integer

NULL_LONG

public static final Long NULL_LONG

The single instance of the magic null object for a Long.

Field Value

Type	Description
Long

NULL_SHORT

public static final Short NULL_SHORT

The single instance of the magic null object for a Short.

Field Value

Type	Description
Short

NULL_STRING

public static final String NULL_STRING

The single instance of the magic null object for a String.

Field Value

Type	Description
String

Static Methods

<T>clone(T data)

public static T <T>clone(T data)

Returns a deep clone of the given key/value data, such that the result is a completely independent copy.

This should not be used directly in the implementation of Object.clone(). Instead use #deepCopy(Object, Object) for that purpose.

Final fields cannot be changed and therefore their value won't be copied.

Parameter

Name	Description
data	`T` key/value data object or map to clone or `null` for a `null` return value

Returns

Type	Description
T	deep clone or `null` for `null` input

<T>nullOf(Class<T> objClass)

public static T <T>nullOf(Class<T> objClass)

Returns the single instance of the magic object that represents the "null" value for the given Java class (including array or enum).

Parameter

Name	Description
objClass	`Class<T>` class of the object needed

Returns

Type	Description
T	magic object instance that represents the "null" value (not Java `null`)

deepCopy(Object src, Object dest)

public static void deepCopy(Object src, Object dest)

Makes a deep copy of the given source object into the destination object that is assumed to be constructed using Object.clone().

Example usage of this method in Object.clone():

@Override public MyObject clone() { try { @SuppressWarnings("unchecked") MyObject result = (MyObject) super.clone(); Data.deepCopy(this, result); return result; } catch (CloneNotSupportedException e) { throw new IllegalStateException(e); } }

Final fields cannot be changed and therefore their value won't be copied.

Parameters

Name	Description
src	`Object` source object
dest	`Object` destination object of identical type as source object, and any contained arrays must be the same length

isNull(Object object)

public static boolean isNull(Object object)

Returns whether the given object is the magic object that represents the null value of its class.

Parameter

Name	Description
object	`Object` object or `null`

Returns

Type	Description
boolean	whether it is the magic null value or `false` for `null` input

isPrimitive(Type type)

public static boolean isPrimitive(Type type)

Returns whether the given type is one of the supported primitive classes like number and date/time, or is a wildcard of one.

A primitive class is any class for whom Class#isPrimitive() is true, as well as any classes of type: Character, String, Integer, Long, Short, Byte, Float, Double, BigInteger, BigDecimal, Boolean, and DateTime.

Parameter

Name	Description
type	`Type` type or `null` for `false` result

Returns

Type	Description
boolean	whether it is a primitive

isValueOfPrimitiveType(Object fieldValue)

public static boolean isValueOfPrimitiveType(Object fieldValue)

Returns whether to given value is null or its class is primitive as defined by Data#isPrimitive(Type).

Parameter

Name	Description
fieldValue	`Object`

Returns

Type	Description
boolean

mapOf(Object data)

public static Map<String,Object> mapOf(Object data)

Returns the map to use for the given data that is treated as a map from string key to some value.

If the input is null, it returns an empty map. If the input is a map, it simply returns the input. Otherwise, it will create a map view using reflection that is backed by the object, so that any changes to the map will be reflected on the object. The map keys of that map view are based on the Key annotation, and null is not a possible map value, although the magic null instance is possible (see <xref uid="com.google.api.client.util.Data.

Parameter

Name	Description
data	`Object` any key value data, represented by an object or a map, or `null`

Returns

Type	Description
Map<String,Object>	key/value map to use

newCollectionInstance(Type type)

public static Collection<Object> newCollectionInstance(Type type)

Returns a new collection instance for the given type.

Creates a new collection instance specified for the first input collection class that matches as follows:

null or an array or assignable from ArrayList (like List or Collection or Object): returns an ArrayList
assignable from HashSet: returns a HashSet
assignable from TreeSet: returns a TreeSet
else: calls <xref uid="com.google.api.client.util.Types.

Parameter

Name	Description
type	`Type` type or `null` for ArrayList.

Returns

Type	Description
Collection<Object>	new collection instance

newMapInstance(Class<?> mapClass)

public static Map<String,Object> newMapInstance(Class<?> mapClass)

Returns a new instance of a map based on the given field class.

Creates a new map instance specified for the first input map class that matches as follows:

null or assignable from ArrayMap (like Map or Object): returns an ArrayMap
assignable from TreeMap (like SortedMap): returns a TreeMap
else: calls <xref uid="com.google.api.client.util.Types.

Parameter

Name	Description
mapClass	`Class<?>` field class

Returns

Type	Description
Map<String,Object>

parsePrimitiveValue(Type type, String stringValue)

public static Object parsePrimitiveValue(Type type, String stringValue)

Parses the given string value based on the given primitive type.

Types are parsed as follows:

Void: null
null or is assignable from String (like Object): no parsing
char or Character: String.charAt(0) (requires length to be exactly 1)
boolean or Boolean: Boolean#valueOf(String)
byte or Byte: Byte#valueOf(String)
short or Short: Short#valueOf(String)
int or Integer: Integer#valueOf(String)
long or Long: Long#valueOf(String)
float or Float: Float#valueOf(String)
double or Double: Double#valueOf(String)
BigInteger: BigInteger(String)
BigDecimal: BigDecimal(String)
DateTime: DateTime#parseRfc3339(String)

Note that this may not be the right behavior for some use cases.

Parameters

Name	Description
type	`Type` primitive type or `null` to parse as a string
stringValue	`String` string value to parse or `null` for `null` result

Returns

Type	Description
Object	parsed object or `null` for `null` input

resolveWildcardTypeOrTypeVariable(List<Type> context, Type type)

public static Type resolveWildcardTypeOrTypeVariable(List<Type> context, Type type)

Aggressively resolves the given type in such a way that the resolved type is not a wildcard type or a type variable, returning Object.class if the type variable cannot be resolved.

Parameters

Name	Description
context	`List<Type>` context list, ordering from least specific to most specific type context, for example container class and then its field
type	`Type` type or `null` for `null` result

Returns

Type	Description
Type	resolved type (which may be class, parameterized type, or generic array type, but not wildcard type or type variable) or `null` for `null` input

Constructors

Data()

public Data()