Top Description Fields Constructors Methods
org.springframework.web.socket

public Class WebSocketExtension

extends Object
Class Inheritance
Known Direct Subclasses
org.springframework.web.socket.adapter.standard.StandardToWebSocketExtensionAdapter
Imports
java.util.ArrayList, .Collections, .List, .Locale, .Map, org.springframework.lang.Nullable, org.springframework.util.Assert, .CollectionUtils, .LinkedCaseInsensitiveMap, .StringUtils
Represents a WebSocket extension as defined in the RFC 6455. WebSocket extensions add protocol features to the WebSocket protocol. The extensions used within a session are negotiated during the handshake phase as follows:

WebSocket Extension HTTP headers may include parameters and follow RFC 7230 section 3.2

Note that the order of extensions in HTTP headers defines their order of execution, e.g. extensions "foo, bar" will be executed as "bar(foo(message))".

Authors
Brian Clozel, Juergen Hoeller
Since
4.0
See Also
WebSocket Protocol Extensions, RFC 6455 - Section 9

Field Summary

Modifier and TypeField and Description
private final String
name

private final Map<String, String>
parameters

Constructor Summary

AccessConstructor and Description
public
WebSocketExtension(String
the name of the extension
name)

Create a WebSocketExtension with the given name.

public
WebSocketExtension(String
the name of the extension
name, Map<String, String>
the parameters
parameters)

Create a WebSocketExtension with the given name and parameters.

Method Summary

Modifier and TypeMethod and Description
public boolean
equals(Object
the reference object with which to compare.
other)

Overrides java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

public String
getName()

Return the name of the extension (never null or empty).

public Map<String, String>
getParameters()

Return the parameters of the extension (never null).

public int
hashCode()

Overrides java.lang.Object.hashCode.

Returns a hash code value for this object.

private static WebSocketExtension
parseExtension(String extension)

public static List<WebSocketExtension>

Returns:

the list of extensions
parseExtensions(String
the string to parse
extensions)

Parse the given, comma-separated string into a list of WebSocketExtension objects.

public String
toString()

Overrides java.lang.Object.toString.

Returns a string representation of the object.

Inherited from java.lang.Object:
clonefinalizegetClassnotifynotifyAllwaitwaitwait

Field Detail

nameback to summary
private final String name
parametersback to summary
private final Map<String, String> parameters

Constructor Detail

WebSocketExtensionback to summary
public WebSocketExtension(String name)

Create a WebSocketExtension with the given name.

Parameters
name:String

the name of the extension

WebSocketExtensionback to summary
public WebSocketExtension(String name, Map<String, String> parameters)

Create a WebSocketExtension with the given name and parameters.

Parameters
name:String

the name of the extension

parameters:Map<String, String>

the parameters

Method Detail

equalsback to summary
public boolean equals(Object other)

Overrides java.lang.Object.equals.

Doc from java.lang.Object.equals.

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

  • It is reflexive: for any non-null reference value x, x.equals(x) should return true.
  • It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
  • It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
  • It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
  • For any non-null reference value x, x.equals(null) should return false.

An equivalence relation partitions the elements it operates on into equivalence classes; all the members of an equivalence class are equal to each other. Members of an equivalence class are substitutable for each other, at least for some purposes.

Parameters
other:Object

the reference object with which to compare.

Returns:boolean

true if this object is the same as the obj argument; false otherwise.

Annotations
@Override
getNameback to summary
public String getName()

Return the name of the extension (never null or empty).

getParametersback to summary
public Map<String, String> getParameters()

Return the parameters of the extension (never null).

hashCodeback to summary
public int hashCode()

Overrides java.lang.Object.hashCode.

Doc from java.lang.Object.hashCode.

Returns a hash code value for this object. This method is supported for the benefit of hash tables such as those provided by java.util.HashMap.

The general contract of hashCode is:

  • Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
  • If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
  • It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
Returns:int

a hash code value for this object

Annotations
@Override
parseExtensionback to summary
private static WebSocketExtension parseExtension(String extension)
parseExtensionsback to summary
public static List<WebSocketExtension> parseExtensions(String extensions)

Parse the given, comma-separated string into a list of WebSocketExtension objects.

This method can be used to parse a "Sec-WebSocket-Extension" header.

Parameters
extensions:String

the string to parse

Returns:List<WebSocketExtension>

the list of extensions

Exceptions
IllegalArgumentException:
if the string cannot be parsed
toStringback to summary
public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object. Satisfying this method's contract implies a non-null result must be returned.

Returns:String

a string representation of the object

Annotations
@Override