com.oracle.crypto.keypair

Class KeyPairGenerator

java.lang.Object

com.oracle.crypto.keypair.KeyPairGenerator

public abstract class KeyPairGenerator
extends java.lang.Object

The KeyPairGenerator class is used to generate pairs of public and private keys. Key pair generators are constructed using the getInstance factory methods (static methods that return instances of a given class).

A Key pair generator for a particular algorithm creates a public/private key pair that can be used with this algorithm. It also associates algorithm-specific parameters with each of the generated keys.

There are two ways to generate a key pair: in an algorithm-independent manner, and in an algorithm-specific manner. The only difference between the two is the initialization of the object:

• Algorithm-Independent Initialization

  All key pair generators share the concepts of a keysize. The keysize is interpreted differently for different algorithms. There is an initialize method in this KeyPairGenerator class that takes just a keysize argument.

• Algorithm-Specific Initialization

  For situations where a set of algorithm-specific parameters already exists, there is initialize methods that have an AlgorithmParameterSpec argument.

Every implementation of the Java platform is required to support the following standard KeyPairGenerator algorithms and keysizes in parentheses:

• RSA (1024, 2048)

These algorithms are described in the KeyPairGenerator section of the Java Cryptography Architecture Standard Algorithm Name Documentation. Consult the release documentation for your implementation to see if any other algorithms are supported.

See Also:

AlgorithmParameterSpec

Method Summary

Methods

Modifier and Type	Method and Description
KeyPair	generateKeyPair() Generates a key pair.
KeyPair	genKeyPair() Generates a key pair.
java.lang.String	getAlgorithm() Returns the standard name of the algorithm for this key pair generator.
static KeyPairGenerator	getInstance(java.lang.String algorithm) Returns a KeyPairGenerator object that generates public/private key pairs for the specified algorithm.
void	initialize(java.security.spec.AlgorithmParameterSpec params) Initializes the key pair generator using the specified parameter set That initialize method always throws an UnsupportedOperationException if it is not overridden
void	initialize(int keysize) Initializes the key pair generator for a certain keysize using

Methods inherited from class java.lang.Object

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

Method Detail

getAlgorithm

public java.lang.String getAlgorithm()

Returns the standard name of the algorithm for this key pair generator. See the KeyPairGenerator section in the Java Cryptography Architecture Standard Algorithm Name Documentation for information about standard algorithm names.

Returns:

the standard string name of the algorithm.

getInstance

public static KeyPairGenerator getInstance(java.lang.String algorithm)
                                    throws java.security.NoSuchAlgorithmException

Returns a KeyPairGenerator object that generates public/private key pairs for the specified algorithm.

Parameters:

algorithm - the standard string name of the algorithm. See the KeyPairGenerator section in the Java Cryptography Architecture Standard Algorithm Name Documentation for information about standard algorithm names.

Returns:

the new KeyPairGenerator object.

Throws:

java.security.NoSuchAlgorithmException - thrown then algorithm has wrong/unsupported algorithm name

initialize

public void initialize(int keysize)
                throws InvalidParameterException

Initializes the key pair generator for a certain keysize using

Parameters:

keysize - the keysize. This is an algorithm-specific metric, such as modulus length, specified in number of bits.

Throws:

InvalidParameterException - if the keysize is not supported by this KeyPairGenerator object.

initialize

public void initialize(java.security.spec.AlgorithmParameterSpec params)
                throws java.security.InvalidAlgorithmParameterException

Initializes the key pair generator using the specified parameter set That initialize method always throws an UnsupportedOperationException if it is not overridden

Parameters:

params - the parameter set used to generate the keys.

Throws:

java.security.InvalidAlgorithmParameterException - if the given parameters are inappropriate for this key pair generator.

genKeyPair

public final KeyPair genKeyPair()

Generates a key pair.

This will generate a new key pair every time it is called.

This method is functionally equivalent to generateKeyPair.

Returns:

the generated key pair

generateKeyPair

public KeyPair generateKeyPair()

Generates a key pair.

This will generate a new key pair every time it is called.

This method is functionally equivalent to genKeyPair.

Returns:

the generated key pair