Java example source code file (PrincipalImpl.java)

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Java - Java tags/keywords

inetaddress, net, network, principalimpl, serializable, string, unknownhostexception

The PrincipalImpl.java Java example source code

/*
 * Copyright (c) 1997, 2007, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */


package com.sun.jmx.snmp.IPAcl;



import java.net.InetAddress;
import java.net.UnknownHostException;
import java.io.Serializable;


/**
 * Principal represents a host.
 *
 */

class PrincipalImpl implements java.security.Principal, Serializable {
    private static final long serialVersionUID = -7910027842878976761L;

    private InetAddress[] add = null;

    /**
     * Constructs a principal with the local host.
     */
    public PrincipalImpl () throws UnknownHostException {
        add = new InetAddress[1];
        add[0] = java.net.InetAddress.getLocalHost();
    }

    /**
     * Construct a principal using the specified host.
     * <P>
     * The host can be either:
     * <UL>
     * <LI> a host name
     * <LI> an IP address
     * </UL>
     *
     * @param hostName the host used to make the principal.
     */
    public PrincipalImpl(String hostName) throws UnknownHostException {
        if ((hostName.equals("localhost")) || (hostName.equals("127.0.0.1"))) {
            add = new InetAddress[1];
            add[0] = java.net.InetAddress.getByName(hostName);
        }
        else
            add = java.net.InetAddress.getAllByName( hostName );
    }

    /**
     * Constructs a principal using an Internet Protocol (IP) address.
     *
     * @param address the Internet Protocol (IP) address.
     */
    public PrincipalImpl(InetAddress address) {
        add = new InetAddress[1];
        add[0] = address;
    }

    /**
     * Returns the name of this principal.
     *
     * @return the name of this principal.
     */
    public String getName() {
        return add[0].toString();
    }

    /**
     * Compares this principal to the specified object. Returns true if the
     * object passed in matches the principal
     * represented by the implementation of this interface.
     *
     * @param a the principal to compare with.
     * @return true if the principal passed in is the same as that encapsulated by this principal, false otherwise.
     */
    public boolean equals(Object a) {
        if (a instanceof PrincipalImpl){
            for(int i = 0; i < add.length; i++) {
                if(add[i].equals (((PrincipalImpl) a).getAddress()))
                    return true;
            }
            return false;
        } else {
            return false;
        }
    }

    /**
     * Returns a hashcode for this principal.
     *
     * @return a hashcode for this principal.
     */
    public int hashCode(){
        return add[0].hashCode();
    }

    /**
     * Returns a string representation of this principal. In case of multiple address, the first one is returned.
     *
     * @return a string representation of this principal.
     */
    public String toString() {
        return ("PrincipalImpl :"+add[0].toString());
    }

    /**
     * Returns the Internet Protocol (IP) address for this principal. In case of multiple address, the first one is returned.
     *
     * @return the Internet Protocol (IP) address for this principal.
     */
    public InetAddress getAddress(){
        return add[0];
    }

    /**
     * Returns the Internet Protocol (IP) address for this principal. In case of multiple address, the first one is returned.
     *
     * @return the array of Internet Protocol (IP) addresses for this principal.
     */
    public InetAddress[] getAddresses(){
        return add;
    }
}