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 * Copyright (c) 1998, 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

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 */

package com.sun.jmx.snmp;

/**

 * Defines the interface of the object in charge of encoding and decoding SNMP packets.

 * <P>

 * You will not usually need to use this interface, except if you

 * decide to replace the default implementation <CODE>SnmpPduFactoryBER</CODE>.

 * <P>

 * An <CODE>SnmpPduFactory</CODE> object is attached to an

 * {@link com.sun.jmx.snmp.daemon.SnmpAdaptorServer SNMP protocol adaptor}

 * or an {@link com.sun.jmx.snmp.SnmpPeer SnmpPeer}.

 * It is used each time an SNMP packet needs to be encoded or decoded.

 * <BR>{@link com.sun.jmx.snmp.SnmpPduFactoryBER SnmpPduFactoryBER} is the default

 * implementation.

 * It simply applies the standard ASN.1 encoding and decoding

 * on the bytes of the SNMP packet.

 * <P>

 * It's possible to implement your own <CODE>SnmpPduFactory</CODE>

 * object and to add authentication and/or encryption to the

 * default encoding/decoding process.

 *

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

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

 * @see SnmpPduFactory

 * @see SnmpPduPacket

 * @see SnmpMessage

 *

 */

public interface SnmpPduFactory {

    /**

     * Decodes the specified <CODE>SnmpMsg</CODE> and returns the

     * resulting <CODE>SnmpPdu</CODE>. If this method returns

     * <CODE>null</CODE>, the message will be considered unsafe

     * and will be dropped.

     *

     * @param msg The <CODE>SnmpMsg</CODE> to be decoded.

     * @return Null or a fully initialized <CODE>SnmpPdu</CODE>.

     * @exception SnmpStatusException If the encoding is invalid.

     *

     * @since 1.5

     */

    public SnmpPdu decodeSnmpPdu(SnmpMsg msg) throws SnmpStatusException ;

    /**

     * Encodes the specified <CODE>SnmpPdu</CODE> and

     * returns the resulting <CODE>SnmpMsg</CODE>. If this

     * method returns null, the specified <CODE>SnmpPdu</CODE>

     * will be dropped and the current SNMP request will be

     * aborted.

     *

     * @param p The <CODE>SnmpPdu</CODE> to be encoded.

     * @param maxDataLength The size limit of the resulting encoding.

     * @return Null or a fully encoded <CODE>SnmpMsg</CODE>.

     * @exception SnmpStatusException If <CODE>pdu</CODE> contains

     *            illegal values and cannot be encoded.

     * @exception SnmpTooBigException If the resulting encoding does not

     *            fit into <CODE>maxPktSize</CODE> bytes.

     *

     * @since 1.5

     */

    public SnmpMsg encodeSnmpPdu(SnmpPdu p, int maxDataLength)

        throws SnmpStatusException, SnmpTooBigException ;

}