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 * 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

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package com.sun.jmx.snmp.agent;

// java imports

//

import java.io.Serializable;

import java.util.Vector;

import java.util.Enumeration;

// jmx imports

//

import com.sun.jmx.snmp.SnmpOid;

/**

 * Represents a SNMP index.

 * An <CODE>SnmpIndex</CODE> is represented as a <CODE>Vector</CODE> of <CODE>SnmpOid</CODE>.

 * <P>

 * This class is used internally and by the classes generated by <CODE>mibgen</CODE>.

 * You should not need to use this class directly.

 *

 * <p><b>This API is a Sun Microsystems internal API  and is subject

 * to change without notice.</b></p>

 */

public class SnmpIndex implements Serializable {

    private static final long serialVersionUID = 8712159739982192146L;

    /**

     * Initializes an <CODE>SnmpIndex</CODE> using a vector of object identifiers.

     * <P>Following the RFC recommendations, every syntax that is used as a

     * table index should have an object identifier representation. There are

     * some guidelines on how to map the different syntaxes into an object identifier.

     * In the different <CODE>SnmpValue</CODE> classes provided, there is a <CODE>toOid</CODE> method to get

     * the object identifier of the value.

     *

     * @param oidList The list of Object Identifiers.

     */

    public SnmpIndex(SnmpOid[] oidList) {

        size= oidList.length;

        for(int i= 0; i <size; i++) {

            // The order is important ...

            //

            oids.addElement(oidList[i]);

        }

    }

    /**

     * Initializes an <CODE>SnmpIndex</CODE> using the specified Object Identifier.

     *

     * @param oid The Object Identifier.

     */

    public SnmpIndex(SnmpOid oid) {

        oids.addElement(oid);

        size= 1;

    }

    /**

     * Gets the number of Object Identifiers the index is made of.

     *

     * @return The number of Object Identifiers.

     */

    public int getNbComponents() {

        return size;

    }

    /**

     * Gets the index as a vector of Object Identifiers.

     *

     * @return The index as a vector.

     */

    public Vector<SnmpOid> getComponents() {

        return oids;

    }

    /**

     * Compares two indexes for equality.

     *

     * @param index The index to compare <CODE>this</CODE> with.

     *

     * @return <CODE>true</CODE> if the two indexes are equal, <CODE>false</CODE> otherwise.

     */

    public boolean equals(SnmpIndex index) {

        if (size != index.getNbComponents())

            return false;

        // The two vectors have the same length.

        // Compare each single element ...

        //

        SnmpOid oid1;

        SnmpOid oid2;

        Vector<SnmpOid> components= index.getComponents();

        for(int i=0; i <size; i++) {

            oid1= oids.elementAt(i);

            oid2= components.elementAt(i);

            if (oid1.equals(oid2) == false)

                return false;

        }

        return true;

    }

    /**

     * Compares two indexes.

     *

     * @param index The index to compare <CODE>this</CODE> with.

     *

     * @return The value 0 if the two OID vectors have the same elements, another value otherwise.

     */

    public int compareTo(SnmpIndex index) {

        int length= index.getNbComponents();

        Vector<SnmpOid> components= index.getComponents();

        SnmpOid oid1;

        SnmpOid oid2;

        int comp;

        for(int i=0; i < size; i++) {

            if ( i > length) {

                // There is no more element in the index

                //

                return 1;

            }

            // Access the element ...

            //

            oid1= oids.elementAt(i);

            oid2= components.elementAt(i);

            comp= oid1.compareTo(oid2);

            if (comp == 0)

                continue;

            return comp;

        }

        return 0;

    }

    /**

     * Returns a <CODE>String</CODE> representation of the index.

     * The different elements are separated by "//".

     *

     * @return A string representation of the index.

     */

    @Override

    public String toString() {

        final StringBuilder msg= new StringBuilder();

        for(Enumeration<SnmpOid> e= oids.elements(); e.hasMoreElements(); ) {

            SnmpOid val= e.nextElement();

            msg.append("//").append( val.toString());

        }

        return msg.toString();

    }

    // PRIVATE VARIABLES

    //------------------

    /**

     * The list of OIDs.

     * @serial

     */

    private Vector<SnmpOid> oids = new Vector<>();

    /**

     * The number of elements in the index.

     * @serial

     */

    private int size = 0;

}