com.google.crypto.tink

Class KeysetHandle.Builder

java.lang.Object

com.google.crypto.tink.KeysetHandle.Builder

Enclosing class:

KeysetHandle

public static final class KeysetHandle.Builder
extends Object

Used to create new KeysetHandle objects.

A builder can be used to create a new KeysetHandle object. To create a builder with an empty keyset, one calls KeysetHandle.newBuilder();. To create a builder from an existing keyset, one calls KeysetHandle.newBuilder(keyset);.

To add a new key to a Builder, one calls addEntry(com.google.crypto.tink.KeysetHandle.Builder.Entry) with a KeysetEntry object. Such objects can be created

• From a named Parameters with KeysetHandle.generateEntryFromParametersName(java.lang.String),
• From a Parameters object, with KeysetHandle.generateEntryFromParameters(com.google.crypto.tink.Parameters),
• By importing an existing key, with KeysetHandle.importKey(com.google.crypto.tink.Key)

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All these functions return a KeysetBuilder.Entry. It is necessary to assign an ID to a new entry by calling one of Entry#withNextId, KeysetHandle.Builder.Entry.withFixedId(int), or KeysetHandle.Builder.Entry.withRandomId(). The exception is when an existing key which has an id requirement is imported (in which case the required ID is used).

It is possible to set the status of an entry by calling KeysetHandle.Builder.Entry.setStatus(com.google.crypto.tink.KeyStatus). The Status defaults to ENABLED.

It is possible to set whether an entry is the primary by calling KeysetHandle.Builder.Entry.makePrimary(). The user must ensure that once build() is called, a primary has been set.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	KeysetHandle.Builder.Entry One entry, representing a single key, in a Keyset.Builder.

Constructor Summary

Constructors

Constructor and Description
Builder()

Method Summary

Modifier and Type	Method and Description
KeysetHandle.Builder	addEntry(KeysetHandle.Builder.Entry entry) Adds an entry to a keyset
KeysetHandle	build() Creates a new KeysetHandle.
KeysetHandle.Builder.Entry	getAt(int i) Returns the entry at index i, 0 <= i < size().
KeysetHandle.Builder.Entry	removeAt(int i) Removes the entry at index i.
int	size() Returns the number of entries in this builder.

Methods inherited from class java.lang.Object

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

Constructor Detail

Builder

public Builder()

Method Detail

addEntry

public KeysetHandle.Builder addEntry(KeysetHandle.Builder.Entry entry)

Adds an entry to a keyset

size

public int size()

Returns the number of entries in this builder.

getAt

public KeysetHandle.Builder.Entry getAt(int i)

Returns the entry at index i, 0 <= i < size().

Throws:

IndexOutOfBoundsException - if i < 0 or i >= size();

removeAt

public KeysetHandle.Builder.Entry removeAt(int i)

Removes the entry at index i.

build

public KeysetHandle build()
                   throws GeneralSecurityException

Creates a new KeysetHandle.

Throws a GeneralSecurityException if one of the following holds

• No entry was marked as primary
• There is an entry in which the ID has not been set and which did not have a predefined ID (see KeysetHandle.Builder.Entry).
• There is a withRandomId-entry which is followed by a non withRandomId-entry
• There are two entries with the same withFixedId (including pre-existing keys and imported keys which have an id requirement).
• There is a withNextId entry, but there previously was an entry which has an ID of MAX_INTEGER.

Throws:

GeneralSecurityException