Java example source code file (Oid.java)

This example Java source code file (Oid.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

deroutputstream, dervalue, gssexception, improperly, ioexception, objectidentifier, oid, string

The Oid.java Java example source code

/*
 * Copyright (c) 2000, 2011, 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 org.ietf.jgss;

import java.io.InputStream;
import java.io.IOException;
import sun.security.util.DerValue;
import sun.security.util.DerOutputStream;
import sun.security.util.ObjectIdentifier;

/**
 * This class represents Universal Object Identifiers (Oids) and their
 * associated operations.<p>
 *
 * Oids are hierarchically globally-interpretable identifiers used
 * within the GSS-API framework to identify mechanisms and name formats.<p>
 *
 * The structure and encoding of Oids is defined in ISOIEC-8824 and
 * ISOIEC-8825.  For example the Oid representation of Kerberos V5
 * mechanism is "1.2.840.113554.1.2.2"<p>
 *
 * The GSSName name class contains public static Oid objects
 * representing the standard name types defined in GSS-API.
 *
 * @author Mayank Upadhyay
 * @since 1.4
 */
public class Oid {

    private ObjectIdentifier oid;
    private byte[] derEncoding;

    /**
     * Constructs an Oid object from a string representation of its
     * integer components.
     *
     * @param strOid the dot separated string representation of the oid.
     * For instance, "1.2.840.113554.1.2.2".
     * @exception GSSException may be thrown when the string is incorrectly
     *     formatted
     */
    public Oid(String strOid) throws GSSException {

        try {
            oid = new ObjectIdentifier(strOid);
            derEncoding = null;
        } catch (Exception e) {
            throw new GSSException(GSSException.FAILURE,
                          "Improperly formatted Object Identifier String - "
                          + strOid);
        }
    }

    /**
     * Creates an Oid object from its ASN.1 DER encoding.  This refers to
     * the full encoding including tag and length.  The structure and
     * encoding of Oids is defined in ISOIEC-8824 and ISOIEC-8825.  This
     * method is identical in functionality to its byte array counterpart.
     *
     * @param derOid stream containing the DER encoded oid
     * @exception GSSException may be thrown when the DER encoding does not
     *  follow the prescribed format.
     */
    public Oid(InputStream derOid) throws GSSException {
        try {
            DerValue derVal = new DerValue(derOid);
            derEncoding = derVal.toByteArray();
            oid = derVal.getOID();
        } catch (IOException e) {
            throw new GSSException(GSSException.FAILURE,
                          "Improperly formatted ASN.1 DER encoding for Oid");
        }
    }


    /**
     * Creates an Oid object from its ASN.1 DER encoding.  This refers to
     * the full encoding including tag and length.  The structure and
     * encoding of Oids is defined in ISOIEC-8824 and ISOIEC-8825.  This
     * method is identical in functionality to its InputStream conterpart.
     *
     * @param data byte array containing the DER encoded oid
     * @exception GSSException may be thrown when the DER encoding does not
     *     follow the prescribed format.
     */
    public Oid(byte [] data) throws GSSException {
        try {
            DerValue derVal = new DerValue(data);
            derEncoding = derVal.toByteArray();
            oid = derVal.getOID();
        } catch (IOException e) {
            throw new GSSException(GSSException.FAILURE,
                          "Improperly formatted ASN.1 DER encoding for Oid");
        }
    }

    /**
     * Only for calling by initializators used with declarations.
     *
     * @param strOid
     */
    static Oid getInstance(String strOid) {
        Oid retVal = null;
        try {
            retVal =  new Oid(strOid);
        } catch (GSSException e) {
            // squelch it!
        }
        return retVal;
    }

    /**
     * Returns a string representation of the oid's integer components
     * in dot separated notation.
     *
     * @return string representation in the following format: "1.2.3.4.5"
     */
    public String toString() {
        return oid.toString();
    }

    /**
     * Tests if two Oid objects represent the same Object identifier
     * value.
     *
     * @return <code>true if the two Oid objects represent the same
     * value, <code>false otherwise.
     * @param other the Oid object that has to be compared to this one
     */
    public boolean equals(Object other) {

        //check if both reference the same object
        if (this == other)
            return (true);

        if (other instanceof Oid)
            return this.oid.equals((Object)((Oid) other).oid);
        else if (other instanceof ObjectIdentifier)
            return this.oid.equals(other);
        else
            return false;
    }


    /**
     * Returns the full ASN.1 DER encoding for this oid object, which
     * includes the tag and length.
     *
     * @return byte array containing the DER encoding of this oid object.
     * @exception GSSException may be thrown when the oid can't be encoded
     */
    public byte[] getDER() throws GSSException {

        if (derEncoding == null) {
            DerOutputStream dout = new DerOutputStream();
            try {
                dout.putOID(oid);
            } catch (IOException e) {
                throw new GSSException(GSSException.FAILURE, e.getMessage());
            }
            derEncoding = dout.toByteArray();
        }

        return derEncoding.clone();
    }

    /**
     * A utility method to test if this Oid value is contained within the
     * supplied Oid array.
     *
     * @param oids the array of Oid's to search
     * @return true if the array contains this Oid value, false otherwise
     */
    public boolean containedIn(Oid[] oids) {

        for (int i = 0; i < oids.length; i++) {
            if (oids[i].equals(this))
                return (true);
        }

        return (false);
    }


    /**
     * Returns a hashcode value for this Oid.
     *
     * @return a hashCode value
     */
    public int hashCode() {
        return oid.hashCode();
    }
}