src/net/java/sip/communicator/impl/protocol/jabber/OperationSetPersistentPresenceJabberImpl.java
/**
     * Removes a subscription for the presence status of the specified
     * contact.
     *
     * @param contact the contact whose status updates we are unsubscribing
     *   from.
     * @throws IllegalArgumentException if <tt>contact</tt> is not a contact
     *   known to the underlying protocol provider
     * @throws IllegalStateException if the underlying protocol provider is
     *   not registered/signed on a public service.
     * @throws OperationFailedException with code NETWORK_FAILURE if
     *   unsubscribing fails due to errors experienced during network
     *   communication
     */
Removes a subscription for the presence status of the specified
contact.

@param contact the contact whose status updates we are unsubscribing
from.
@throws IllegalArgumentException if contact is not a contact
known to the underlying protocol provider
@throws IllegalStateException if the underlying protocol provider is
not registered/signed on a public service.
@throws OperationFailedException with code NETWORK_FAILURE if
unsubscribing fails due to errors experienced during network
communication
Removes a subscription for the presence status of the specified contact . @param contact the contact whose status updates we are unsubscribing from . @throws IllegalArgumentException if contact is not a contact known to the underlying protocol provider @throws IllegalStateException if the underlying protocol provider is not registered / signed on a public service . @throws OperationFailedException with code NETWORK_FAILURE if unsubscribing fails due to errors experienced during network communication
public void unsubscribe(Contact contact) throws IllegalArgumentException,
        IllegalStateException, OperationFailedException
    {
        assertConnected();
        if(! (contact instanceof ContactJabberImpl) )
            throw new IllegalArgumentException(
                "Argument is not an jabber contact (contact=" + contact + ")");
        ssContactList.removeContact((ContactJabberImpl)contact);
    }
public void unsubscribe ( Contact contact ) throws IllegalArgumentException , IllegalStateException , OperationFailedException { assertConnected ( ) ; if ( ! ( contact instanceof ContactJabberImpl ) ) throw new IllegalArgumentException ( "Argument is not an jabber contact (contact=" + contact + ")" ) ; ssContactList . removeContact ( ( ContactJabberImpl ) contact ) ; }
Removes a subscription for the presence status of the specified
 contact.
Removes a subscription for the presence status of the specified contact .