/*

 * Copyright (c) 1999, 2002, 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.jndi.ldap;

import java.io.IOException;

/**

 * This class implements the LDAPv3 Request Control for the persistent search

 * mechanism as defined in

 * <a href="http://www.ietf.org/internet-drafts/draft-ietf-ldapext-psearch-02.txt">draft-ietf-ldapext-psearch-02.txt</a>.

 *

 * The control's value has the following ASN.1 definition:

 * <pre>

 *

 *     PersistentSearch ::= SEQUENCE {

 *         changeTypes INTEGER,

 *         changesOnly BOOLEAN,

 *         returnECs BOOLEAN

 *     }

 *

 * </pre>

 *

 * @see EntryChangeResponseControl

 * @author Vincent Ryan

 */

final public class PersistentSearchControl extends BasicControl {

    /**

     * The persistent search control's assigned object identifier

     * is 2.16.840.1.113730.3.4.3.

     */

    public static final String OID = "2.16.840.1.113730.3.4.3";

    /**

     * Indicates interest in entries which have been added.

     */

    public static final int ADD = 1;

    /**

     * Indicates interest in entries which have been deleted.

     */

    public static final int DELETE = 2;

    /**

     * Indicates interest in entries which have been modified.

     */

    public static final int MODIFY = 4;

    /**

     * Indicates interest in entries which have been renamed.

     */

    public static final int RENAME = 8;

    /**

     * Indicates interest in entries which have been added, deleted,

     * modified or renamed.

     */

    public static final int ANY = ADD | DELETE | MODIFY | RENAME;

    /**

     * The change types of interest. All changes, by default.

     *

     * @serial

     */

    private int changeTypes = ANY;

    /**

     * Return original entries and changed entries or only changed entries.

     *

     * @serial

     */

    private boolean changesOnly = false;

    /**

     * Return entry change controls.

     *

     * @serial

     */

    private boolean returnControls = true;

    private static final long serialVersionUID = 6335140491154854116L;

    /**

     * Constructs a persistent search non-critical control.

     * The original entries, any changed entries (additions,

     * deletions, modifications or renames) and entry change

     * controls are requested.

     *

     * @exception IOException If a BER encoding error occurs.

     */

    public PersistentSearchControl() throws IOException {

        super(OID);

        super.value = setEncodedValue();

    }

    /**

     * Constructs a persistent search control.

     *

     * @param   changeTypes     The change types of interest.

     * @param   changesOnly     Return original entries and changed entries

     *                          or only the changed entries.

     * @param   returnControls  Return entry change controls.

     * @param   criticality     The control's criticality.

     * @exception IOException If a BER encoding error occurs.

     */

    public PersistentSearchControl(int changeTypes, boolean changesOnly,

        boolean returnControls, boolean criticality) throws IOException {

        super(OID, criticality, null);

        this.changeTypes = changeTypes;

        this.changesOnly = changesOnly;

        this.returnControls = returnControls;

        super.value = setEncodedValue();

    }

    /*

     * Sets the ASN.1 BER encoded value of the persistent search control.

     * The result is the raw BER bytes including the tag and length of

     * the control's value. It does not include the controls OID or criticality.

     *

     * @return A possibly null byte array representing the ASN.1 BER encoded

     *         value of the LDAP persistent search control.

     * @exception IOException If a BER encoding error occurs.

     */

    private byte[] setEncodedValue() throws IOException {

        // build the ASN.1 encoding

        BerEncoder ber = new BerEncoder(32);

        ber.beginSeq(Ber.ASN_SEQUENCE | Ber.ASN_CONSTRUCTOR);

            ber.encodeInt(changeTypes);

            ber.encodeBoolean(changesOnly);

            ber.encodeBoolean(returnControls);

        ber.endSeq();

        return ber.getTrimmedBuf();

    }

}