com.google.crypto.tink.internal

Class KeyParser<SerializationT extends Serialization>

java.lang.Object

com.google.crypto.tink.internal.KeyParser<SerializationT>

public abstract class KeyParser<SerializationT extends Serialization>
extends Object

Parses Serialization objects into Key objects of a certain kind.

This class should eventually be in Tinks public API -- however, it might still change before that.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	KeyParser.KeyParsingFunction<SerializationT extends Serialization> A function which parses a key.

Method Summary

Modifier and Type	Method and Description
static <SerializationT extends Serialization> KeyParser<SerializationT>	create(KeyParser.KeyParsingFunction<SerializationT> function, Bytes objectIdentifier, Class<SerializationT> serializationClass) Creates a KeyParser object.
Bytes	getObjectIdentifier() Returns the objectIdentifier for this serialization.
Class<SerializationT>	getSerializationClass()
abstract Key	parseKey(SerializationT serialization, SecretKeyAccess access) Parses a serialization into a key.

Methods inherited from class java.lang.Object

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

Method Detail

parseKey

public abstract Key parseKey(SerializationT serialization,
                             @Nullable
                             SecretKeyAccess access)
                      throws GeneralSecurityException

Parses a serialization into a key.

This function is usually called with a Serialization matching the result of getObjectIdentifier. However, implementations should check that this is the case.

Throws:

GeneralSecurityException

getObjectIdentifier

public final Bytes getObjectIdentifier()

Returns the objectIdentifier for this serialization.

The object identifier is a unique identifier per registry for this object (in the standard proto serialization, it is the typeUrl). In other words, when registering a KeyParser, the registry will invoke this to get the handled object identifier. In order to parse an object of type SerializationT, the registry will then obtain the objectIdentifier of this serialization object, and call the parser corresponding to this object.

getSerializationClass

public final Class<SerializationT> getSerializationClass()

create

public static <SerializationT extends Serialization> KeyParser<SerializationT> create(KeyParser.KeyParsingFunction<SerializationT> function,
                                                                                      Bytes objectIdentifier,
                                                                                      Class<SerializationT> serializationClass)

Creates a KeyParser object.

In order to create a KeyParser object, one typically writes a function

 class MyClass {
   private static MyKey parse(MySerialization key, @Nullable SecretKeyAccess access)
             throws GeneralSecurityException {
     ...
   }
 }
 

This function can then be used to create a KeyParser:

 KeyParser<MyKey, MySerialization> parser =
       KeyParser.create(MyClass::parse, objectIdentifier, MySerialization.class);
 

Note that calling this function twice will result in objects which are not equal according to Object.equals, and hence cannot be used to re-register a previously registered object.

Parameters:

function - The function used to parse a Key

objectIdentifier - The identifier to be returned by getObjectIdentifier()

serializationClass - The class object corresponding to SerializationT