Java in a Nutshell, 5th Edition [Electronic resources]

This class generates a public/private key pair for a specified cryptographic algorithm. To create a KeyPairGenerator, call one of the static getInstance( ) methods, specifying the name of the algorithm and, optionally, the name or Provider object of the security provider to use. The default "SUN" provider shipped with Java 1.2 supports only the "DSA" algorithm. The "SunJCE" provider of the Java Cryptography Extension (JCE) additionally supports the "DiffieHellman" algorithm.

Once you have created a KeyPairGenerator, initialize it by calling initialize( ). You can perform an algorithm-independent initialization by simply specifying the desired key size in bits. Alternatively, you can do an algorithm-dependent initialization by providing an appropriate AlgorithmParameterSpec object for the key-generation algorithm. In either case, you may optionally provide your own source of randomness in the guise of a SecureRandom object. Once you have created and initialized a KeyPairGenerator, call genKeyPair( ) to create a KeyPair object. Remember that the KeyPair contains a PrivateKey that

must be kept private.

For historical reasons, KeyPairGenerator extends KeyPairGeneratorSpi. Applications should not use any methods inherited from that class.

public abstract class 
KeyPairGenerator  extends KeyPairGeneratorSpi {
// Protected Constructors
protected 
KeyPairGenerator (String 
algorithm );  
// Public Class Methods
public static KeyPairGenerator 
getInstance (String 
algorithm ) 
throws NoSuchAlgorithmException;  
1.4   public static KeyPairGenerator 
getInstance (String 
algorithm , 
Provider 
provider ) throws NoSuchAlgorithmException;  
public static KeyPairGenerator 
getInstance (String 
algorithm , 
String 
provider ) 
throws NoSuchAlgorithmException, NoSuchProviderException;  
// Public Instance Methods
1.2   public final KeyPair 
genKeyPair ( );  
public String 
getAlgorithm ( );  
1.2   public final Provider 
getProvider ( );  
1.2   public void 
initialize (java.security.spec.AlgorithmParameterSpec 
params ) 
throws InvalidAlgorithmParameterException;  
public void 
initialize (int 
keysize );  
// Public Methods Overriding KeyPairGeneratorSpi
public KeyPair 
generateKeyPair ( );          constant
1.2   public void 
initialize (java.security.spec.AlgorithmParameterSpec 
params , 
SecureRandom 
random ) 
throws InvalidAlgorithmParameterException;     empty
public void 
initialize (int 
keysize , SecureRandom 
random );     empty
}