java.security.cert

Class Certificate

java.lang.Object

java.security.cert.Certificate

All Implemented Interfaces:

java.io.Serializable

Direct Known Subclasses:

X509Certificate

public abstract class Certificate
extends java.lang.Object
implements java.io.Serializable

The Certificate class is an abstract class used to manage identity certificates. An identity certificate is a combination of a principal and a public key which is certified by another principal. This is the puprose of Certificate Authorities (CA).

This class is used to manage different types of certificates but have important common puposes. Different types of certificates like X.509 and OpenPGP share general certificate functions (like encoding and verifying) and information like public keys.

X.509, OpenPGP, and SDSI can be implemented by subclassing this class even though they differ in storage methods and information stored.

Since:

JDK 1.2

See Also:

CertificateFactory, X509Certificate, Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	Certificate.CertificateRep Certificate.CertificateRep is an inner class used to provide an alternate storage mechanism for serialized Certificates.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Certificate(java.lang.String type) Constructs a new certificate of the specified type.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(java.lang.Object other) Compares this Certificate to other.
abstract byte[]	getEncoded() Gets the DER ASN.1 encoded format for this Certificate.
abstract java.security.PublicKey	getPublicKey() Returns the public key stored in the Certificate.
java.lang.String	getType() Returns the Certificate type.
int	hashCode() Returns a hash code for this Certificate in its encoded form.
abstract java.lang.String	toString() Returns a string representing the Certificate.
abstract void	verify(java.security.PublicKey key) Verifies that this Certificate was properly signed with the PublicKey that corresponds to its private key.
abstract void	verify(java.security.PublicKey key, java.lang.String sigProvider) Verifies that this Certificate was properly signed with the PublicKey that corresponds to its private key and uses the signature engine provided by the provider.
protected java.lang.Object	writeReplace() Returns a replacement for this certificate to be serialized.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Certificate

protected Certificate(java.lang.String type)

Constructs a new certificate of the specified type. An example is "X.509".

Parameters:

type - a valid standard name for a certificate.

Method Detail

getType

public final java.lang.String getType()

Returns the Certificate type.

Returns:

a string representing the Certificate type

equals

public boolean equals(java.lang.Object other)

Compares this Certificate to other. It checks if the object if instanceOf Certificate and then checks if the encoded form matches.

Overrides:

equals in class java.lang.Object

Parameters:

other - An Object to test for equality

Returns:

true if equal, false otherwise

See Also:

Object.hashCode()

hashCode

public int hashCode()

Returns a hash code for this Certificate in its encoded form.

Overrides:

hashCode in class java.lang.Object

Returns:

A hash code of this class

See Also:

Object.equals(Object), System.identityHashCode(Object)

getEncoded

public abstract byte[] getEncoded()
                           throws CertificateEncodingException

Gets the DER ASN.1 encoded format for this Certificate. It assumes each certificate has only one encoding format. Ex: X.509 is encoded as ASN.1 DER

Returns:

byte array containg encoded form

Throws:

CertificateEncodingException - if an error occurs

verify

public abstract void verify(java.security.PublicKey key)
                     throws CertificateException,
                            java.security.NoSuchAlgorithmException,
                            java.security.InvalidKeyException,
                            java.security.NoSuchProviderException,
                            java.security.SignatureException

Verifies that this Certificate was properly signed with the PublicKey that corresponds to its private key.

Parameters:

key - PublicKey to verify with

Throws:

CertificateException - encoding error

java.security.NoSuchAlgorithmException - unsupported algorithm

java.security.InvalidKeyException - incorrect key

java.security.NoSuchProviderException - no provider

java.security.SignatureException - signature error

verify

public abstract void verify(java.security.PublicKey key,
          java.lang.String sigProvider)
                     throws CertificateException,
                            java.security.NoSuchAlgorithmException,
                            java.security.InvalidKeyException,
                            java.security.NoSuchProviderException,
                            java.security.SignatureException

Verifies that this Certificate was properly signed with the PublicKey that corresponds to its private key and uses the signature engine provided by the provider.

Parameters:

key - PublicKey to verify with

sigProvider - Provider to use for signature algorithm

Throws:

CertificateException - encoding error

java.security.NoSuchAlgorithmException - unsupported algorithm

java.security.InvalidKeyException - incorrect key

java.security.NoSuchProviderException - incorrect provider

java.security.SignatureException - signature error

toString

public abstract java.lang.String toString()

Returns a string representing the Certificate.

Overrides:

toString in class java.lang.Object

Returns:

a string representing the Certificate.

See Also:

Object.getClass(), Object.hashCode(), Class.getName(), Integer.toHexString(int)

getPublicKey

public abstract java.security.PublicKey getPublicKey()

Returns the public key stored in the Certificate.

Returns:

The public key

writeReplace

protected java.lang.Object writeReplace()
                                 throws java.io.ObjectStreamException

Returns a replacement for this certificate to be serialized. This method returns the equivalent to the following for this class:

new CertificateRep(getType(), getEncoded());

This thusly replaces the certificate with its name and its encoded form, which can be deserialized later with the CertificateFactory implementation for this certificate's type.

Returns:

The replacement object to be serialized.

Throws:

java.io.ObjectStreamException - If the replacement could not be created.