Package dev.getelements.elements.sdk

Interface Attributes

All Known Subinterfaces:

MutableAttributes

All Known Implementing Classes:

GuiceAttributes, ImmutableAttributes, InheritedAttributes, InheritedMutableAttributes, PropertiesAttributes, ServletRequestAttributes, SimpleAttributes

public interface Attributes

Contains attributes which represent contextual information for various types. The test for Object.equals(Object) and Object.hashCode() should be implemented using the provided static methods in this interface, or an equivalent algorithm. Many Attributes implementations exist and the most reliable means must be determined by the contents as they are accessible through this interface and not in an implementation specific way. Failure to do so may result in poor cache performance as Attributes may be a component of a cache key in some parts of the application.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static final record	Attributes.Attribute<T>	Represents a single Attributes.Attribute.

Field Summary

Fields

Modifier and Type	Field	Description
static final Attributes	EMPTY	The empty Attributes implementation.

Method Summary

Modifier and Type	Method	Description
default Map<String,Object>	asMap()	Returns a view of this Attributes object as a Map<String,Object>.
default Properties	asProperties()	Returns this Attributes as a Properties instance, copying all attributes over.
default Properties	asProperties(Properties defaults)	Returns this Attributes as a Properties instance.
static Attributes	emptyAttributes()	Returns EMPTY.
static boolean	equals(Attributes a, Attributes b)	Tests if two Attributes are equal to each other.
static boolean	equals(Attributes a, Object b)	Test if the supplied Attributes is equal to the other Object by first testing if it an instance of Attributes as well as if equals(Attributes, Attributes) returns true.
default Object	getAttribute(String name)	Gets the attribute associated with this Attributes for the given name.
Set<String>	getAttributeNames()	Gets a List<String> containing all attribute names contained in this instance.
Optional<Object>	getAttributeOptional(String name)	Gets the attribute associated with this Attributes object.
static int	hashCode(Attributes attributes)	Given a set of Attributes, this will determined is hash code.
Attributes	immutableCopy()	Returns a copy of this Attributes as an immutable copy.
default Stream<Attributes.Attribute<Object>>	stream()	Gets all Attributes.Attributes as a Stream.

Field Details

EMPTY

static final Attributes EMPTY

The empty Attributes implementation. This returns an empty list of attribute names, and will return null for any requested attribute.

Method Details

getAttributeNames

Set<String> getAttributeNames()

Gets a List<String> containing all attribute names contained in this instance.

Returns:

the List<String> of attribute names

stream

default Stream<Attributes.Attribute<Object>> stream()

Gets all Attributes.Attributes as a Stream.

Returns:

a Stream of Attributes.Attributes

getAttribute

default Object getAttribute(String name)

Gets the attribute associated with this Attributes for the given name. Returning null if no such attribute is found. Note that an attribute may exist with the supplied name and the value null. In order to distinguish from this, the method getAttributeOptional(String) may be used.

Parameters:

name - the name of hte attribute

Returns:

the value or null

getAttributeOptional

Optional<Object> getAttributeOptional(String name)

Gets the attribute associated with this Attributes object.

Parameters:

name - the name of the attribute to fetch

Returns:

an Optional<Object> for the value

immutableCopy

Attributes immutableCopy()

Returns a copy of this Attributes as an immutable copy. Alternatively, if this instance is already immutable, then this will return this instance.

Returns:

an immutable copy of this Attributes

asMap

default Map<String,Object> asMap()

Returns a view of this Attributes object as a Map<String,Object>.

Returns:

this Attributes as a Map<String,Object>

asProperties

default Properties asProperties()

Returns this Attributes as a Properties instance, copying all attributes over.

Returns:

the Properties

asProperties

default Properties asProperties(Properties defaults)

Returns this Attributes as a Properties instance.

Parameters:

defaults - the default properties to use

Returns:

the Properties

emptyAttributes

static Attributes emptyAttributes()

Returns EMPTY.

Returns:

EMPTY

hashCode

static int hashCode(Attributes attributes)

Given a set of Attributes, this will determined is hash code. This must be consistent with the rules of Object.hashCode() and equals(Attributes, Attributes)

Parameters:

attributes - the Attributes

Returns:

the hash code

equals

static boolean equals(Attributes a,
 Object b)

Test if the supplied Attributes is equal to the other Object by first testing if it an instance of Attributes as well as if equals(Attributes, Attributes) returns true.

Parameters:

a - the attributes object

b - another obect

Returns:

true if equal, false otherwise.

equals

static boolean equals(Attributes a,
 Attributes b)

Tests if two Attributes are equal to each other. This is used by subclasses toprovide a universal test for equality against another instance of Attributes. Generally equality is defined as follows:

• The names of all attributes are the same (order notwithstanding)
• The name set of all attributes are equal in size.
• Each individual attribute is equal (as determined by Object.equals(Object)

Parameters:

a - the first Attributes

b - the second Attributes

Returns:

true if equals, false otherwise.