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 * Copyright (c) 1999, 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

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package com.sun.jndi.ldap;

import java.io.IOException;

import java.util.Hashtable;

import java.util.Vector;

import javax.naming.*;

import javax.naming.directory.*;

/**

  * This subclass is used by LDAP to implement the schema calls.

  * Basically, it keeps track of which context it is an attribute of

  *

  * @author Jon Ruiz

  */

final class LdapAttribute extends BasicAttribute {

    static final long serialVersionUID = -4288716561020779584L;

    private transient DirContext baseCtx = null;

    private Name rdn = new CompositeName();

    // these two are used to reconstruct the baseCtx if this attribute has

    // been serialized (

    private String baseCtxURL;

    private Hashtable<String, ? super String> baseCtxEnv;

    @SuppressWarnings("unchecked") // clone()

    public Object clone() {

        LdapAttribute attr = new LdapAttribute(this.attrID, baseCtx, rdn);

        attr.values = (Vector<Object>)values.clone();

        return attr;

    }

    /**

      * Adds a new value to this attribute.

      *

      * @param attrVal The value to be added. If null, a null value is added to

      *                the attribute.

      * @return true Always returns true.

      */

    public boolean add(Object attrVal) {

        // LDAP attributes don't contain duplicate values so there's no need

        // to check if the value already exists before adding it.

        values.addElement(attrVal);

        return true;

    }

    /**

      * Constructs a new instance of an attribute.

      *

      * @param id The attribute's id. It cannot be null.

      */

    LdapAttribute(String id) {

        super(id);

    }

    /**

      * Constructs a new instance of an attribute.

      *

      * @param id The attribute's id. It cannot be null.

      * @param baseCtx  the baseCtx object of this attribute

      * @param rdn      the RDN of the entry (relative to baseCtx)

      */

    private LdapAttribute(String id, DirContext baseCtx, Name rdn) {

        super(id);

        this.baseCtx = baseCtx;

        this.rdn = rdn;

    }

     /**

      * Sets the baseCtx and rdn used to find the attribute's schema

      * Used by LdapCtx.setParents().

      */

    void setParent(DirContext baseCtx, Name rdn) {

        this.baseCtx = baseCtx;

        this.rdn = rdn;

    }

    /**

     * returns the ctx this attribute came from. This call allows

     * LDAPAttribute to be serializable. 'baseCtx' is transient so if

     * it is null, the `baseCtxURL` is used to reconstruct the context

     * to which calls are made.

     */

    private DirContext getBaseCtx() throws NamingException {

        if(baseCtx == null) {

            if (baseCtxEnv == null) {

                baseCtxEnv = new Hashtable<String, String>(3);

            }

            baseCtxEnv.put(Context.INITIAL_CONTEXT_FACTORY,

                             "com.sun.jndi.ldap.LdapCtxFactory");

            baseCtxEnv.put(Context.PROVIDER_URL,baseCtxURL);

            baseCtx = (new InitialDirContext(baseCtxEnv));

        }

        return baseCtx;

    }

    /**

     * This is called when the object is serialized. It is

     * overridden so that the appropriate class variables can be set

     * to re-construct the baseCtx when deserialized. Setting these

     * variables is costly, so it is only done if the object

     * is actually serialized.

     */

    private void writeObject(java.io.ObjectOutputStream out)

        throws IOException {

        // setup internal state

        this.setBaseCtxInfo();

        out.defaultWriteObject();

    }

    /**

     * sets the information needed to reconstruct the baseCtx if

     * we are serialized. This must be called _before_ the object is

     * serialized!!!

     */

    @SuppressWarnings("unchecked") // clone()

    private void setBaseCtxInfo() {

        Hashtable<String, Object> realEnv = null;

        Hashtable<String, Object> secureEnv = null;

        if (baseCtx != null) {

            realEnv = ((LdapCtx)baseCtx).envprops;

            this.baseCtxURL = ((LdapCtx)baseCtx).getURL();

        }

        if(realEnv != null && realEnv.size() > 0 ) {

            // remove any security credentials - otherwise the serialized form

            // would store them in the clear

            for (String key : realEnv.keySet()){

                if (key.indexOf("security") != -1 ) {

                    //if we need to remove props, we must do it to a clone

                    //of the environment. cloning is expensive, so we only do

                    //it if we have to.

                    if(secureEnv == null) {

                        secureEnv = (Hashtable<String, Object>)realEnv.clone();

                    }

                    secureEnv.remove(key);

                }

            }

        }

        // set baseCtxEnv depending on whether we removed props or not

        this.baseCtxEnv = (secureEnv == null ? realEnv : secureEnv);

    }

    /**

      * Retrieves the syntax definition associated with this attribute.

      * @return This attribute's syntax definition.

      */

    public DirContext getAttributeSyntaxDefinition() throws NamingException {

        // get the syntax id from the attribute def

        DirContext schema = getBaseCtx().getSchema(rdn);

        DirContext attrDef = (DirContext)schema.lookup(

            LdapSchemaParser.ATTRIBUTE_DEFINITION_NAME + "/" + getID());

        Attribute syntaxAttr = attrDef.getAttributes("").get("SYNTAX");

        if(syntaxAttr == null || syntaxAttr.size() == 0) {

            throw new NameNotFoundException(

                getID() + " does not have a syntax associated with it");

        }

        String syntaxName = (String)syntaxAttr.get();

        // look in the schema tree for the syntax definition

        return (DirContext)schema.lookup(

            LdapSchemaParser.SYNTAX_DEFINITION_NAME + "/" + syntaxName);

    }

    /**

      * Retrieves this attribute's schema definition.

      *

      * @return This attribute's schema definition.

      */

    public DirContext getAttributeDefinition() throws NamingException {

        DirContext schema = getBaseCtx().getSchema(rdn);

        return (DirContext)schema.lookup(

            LdapSchemaParser.ATTRIBUTE_DEFINITION_NAME + "/" + getID());

    }

}