KeySelector (Java Platform SE 8 ) (original) (raw)

• java.lang.Object

• • javax.xml.crypto.KeySelector

• ---

public abstract class KeySelector
extends Object
A selector that finds and returns a key using the data contained in aKeyInfo object. An example of an implementation of this class is one that searches a KeyStore for trusted keys that match information contained in a KeyInfo.
Whether or not the returned key is trusted and the mechanisms used to determine that is implementation-specific.
Since:
1.6

• • Nested Class Summary

  Nested Classes

  Modifier and Type	Class	Description
  static class	KeySelector.Purpose	The purpose of the key that is to be selected.

  • Constructor Summary

  Constructors

  Modifier	Constructor	Description
  protected	KeySelector()	Default no-args constructor; intended for invocation by subclasses only.

  • Method Summary

  All Methods Static Methods Instance Methods Abstract Methods Concrete Methods

  Modifier and Type	Method	Description
  abstract KeySelectorResult	select(KeyInfo keyInfo,KeySelector.Purpose purpose,AlgorithmMethod method,XMLCryptoContext context)	Attempts to find a key that satisfies the specified constraints.
  static KeySelector	singletonKeySelector(Key key)	Returns a KeySelector that always selects the specified key, regardless of the KeyInfo passed to it.

     * ### Methods inherited from class java.lang.[Object](../../../java/lang/Object.html "class in java.lang")  
     `[clone](../../../java/lang/Object.html#clone--), [equals](../../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../../java/lang/Object.html#finalize--), [getClass](../../../java/lang/Object.html#getClass--), [hashCode](../../../java/lang/Object.html#hashCode--), [notify](../../../java/lang/Object.html#notify--), [notifyAll](../../../java/lang/Object.html#notifyAll--), [toString](../../../java/lang/Object.html#toString--), [wait](../../../java/lang/Object.html#wait--), [wait](../../../java/lang/Object.html#wait-long-), [wait](../../../java/lang/Object.html#wait-long-int-)`

• • Constructor Detail

     * #### KeySelector  
     protected KeySelector()  
     Default no-args constructor; intended for invocation by subclasses only.  

  • Method Detail

    * #### select  
    public abstract [KeySelectorResult](../../../javax/xml/crypto/KeySelectorResult.html "interface in javax.xml.crypto") select([KeyInfo](../../../javax/xml/crypto/dsig/keyinfo/KeyInfo.html "interface in javax.xml.crypto.dsig.keyinfo") keyInfo,  
                                             [KeySelector.Purpose](../../../javax/xml/crypto/KeySelector.Purpose.html "class in javax.xml.crypto") purpose,  
                                             [AlgorithmMethod](../../../javax/xml/crypto/AlgorithmMethod.html "interface in javax.xml.crypto") method,  
                                             [XMLCryptoContext](../../../javax/xml/crypto/XMLCryptoContext.html "interface in javax.xml.crypto") context)  
                                      throws [KeySelectorException](../../../javax/xml/crypto/KeySelectorException.html "class in javax.xml.crypto")  
    Attempts to find a key that satisfies the specified constraints.  
    Parameters:  
    `keyInfo` \- a `KeyInfo` (may be `null`)  
    `purpose` \- the key's purpose ([KeySelector.Purpose.SIGN](../../../javax/xml/crypto/KeySelector.Purpose.html#SIGN),[KeySelector.Purpose.VERIFY](../../../javax/xml/crypto/KeySelector.Purpose.html#VERIFY), [KeySelector.Purpose.ENCRYPT](../../../javax/xml/crypto/KeySelector.Purpose.html#ENCRYPT), or[KeySelector.Purpose.DECRYPT](../../../javax/xml/crypto/KeySelector.Purpose.html#DECRYPT))  
    `method` \- the algorithm method that this key is to be used for. Only keys that are compatible with the algorithm and meet the constraints of the specified algorithm should be returned.  
    `context` \- an `XMLCryptoContext` that may contain useful information for finding an appropriate key. If this key selector supports resolving [RetrievalMethod](../../../javax/xml/crypto/dsig/keyinfo/RetrievalMethod.html "interface in javax.xml.crypto.dsig.keyinfo") types, the context's `baseURI` and `dereferencer` parameters (if specified) should be used by the selector to resolve and dereference the URI.  
    Returns:  
    the result of the key selector  
    Throws:  
    `[KeySelectorException](../../../javax/xml/crypto/KeySelectorException.html "class in javax.xml.crypto")` \- if an exceptional condition occurs while attempting to find a key. Note that an inability to find a key is not considered an exception (`null` should be returned in that case). However, an error condition (ex: network communications failure) that prevented the `KeySelector` from finding a potential key should be considered an exception.  
    `[ClassCastException](../../../java/lang/ClassCastException.html "class in java.lang")` \- if the data type of `method` is not supported by this key selector  
    * #### singletonKeySelector  
    public static [KeySelector](../../../javax/xml/crypto/KeySelector.html "class in javax.xml.crypto") singletonKeySelector([Key](../../../java/security/Key.html "interface in java.security") key)  
    Returns a `KeySelector` that always selects the specified key, regardless of the `KeyInfo` passed to it.  
    Parameters:  
    `key` \- the sole key to be stored in the key selector  
    Returns:  
    a key selector that always selects the specified key  
    Throws:  
    `[NullPointerException](../../../java/lang/NullPointerException.html "class in java.lang")` \- if `key` is `null`

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