/* * Copyright (c) 1999, 2004, 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 javax.naming.directory; import java.util.Vector;import java.util.Enumeration;import java.util.NoSuchElementException; import javax.naming.NamingException;import javax.naming.NamingEnumeration;import javax.naming.OperationNotSupportedException; /**  * This interface represents an attribute associated with a named object.  *<p>  * In a directory, named objects can have associated with them  * attributes.  The <tt>Attribute</tt> interface represents an attribute associated  * with a named object.  An attribute contains 0 or more, possibly null, values.  * The attribute values can be ordered or unordered (see <tt>isOrdered()</tt>).  * If the values are unordered, no duplicates are allowed.  * If the values are ordered, duplicates are allowed.  *<p>  * The content and representation of an attribute and its values is defined by  * the attribute's <em>schema</em>. The schema contains information  * about the attribute's syntax and other properties about the attribute.  * See <tt>getAttributeDefinition()</tt> and  * <tt>getAttributeSyntaxDefinition()</tt>  * for details regarding how to get schema information about an attribute  * if the underlying directory service supports schemas.  *<p>  * Equality of two attributes is determined by the implementation class.  * A simple implementation can use <tt>Object.equals()</tt> to determine equality  * of attribute values, while a more sophisticated implementation might  * make use of schema information to determine equality.  * Similarly, one implementation might provide a static storage  * structure which simply returns the values passed to its  * constructor, while another implementation might define <tt>get()</tt> and  * <tt>getAll()</tt>.  * to get the values dynamically from the directory.  *<p>  * Note that updates to <tt>Attribute</tt> (such as adding or removing a  * value) do not affect the corresponding representation of the attribute  * in the directory.  Updates to the directory can only be effected  * using operations in the <tt>DirContext</tt> interface.  *  * @author Rosanna Lee  * @author Scott Seligman  *  * @see BasicAttribute  * @since 1.3  */public interface Attribute extends Cloneable, java.io.Serializable {    /**      * Retrieves an enumeration of the attribute's values.      * The behaviour of this enumeration is unspecified      * if the attribute's values are added, changed,      * or removed while the enumeration is in progress.      * If the attribute values are ordered, the enumeration's items      * will be ordered.      *      * @return A non-null enumeration of the attribute's values.      * Each element of the enumeration is a possibly null Object. The object's      * class is the class of the attribute value. The element is null      * if the attribute's value is null.      * If the attribute has zero values, an empty enumeration      * is returned.      * @exception NamingException      *         If a naming exception was encountered while retrieving      *         the values.      * @see #isOrdered      */    NamingEnumeration<?> getAll() throws NamingException;     /**      * Retrieves one of this attribute's values.      * If the attribute has more than one value and is unordered, any one of      * the values is returned.      * If the attribute has more than one value and is ordered, the      * first value is returned.      *      * @return A possibly null object representing one of      *        the attribute's value. It is null if the attribute's value      *        is null.      * @exception NamingException      *         If a naming exception was encountered while retrieving      *         the value.      * @exception java.util.NoSuchElementException      *         If this attribute has no values.      */    Object get() throws NamingException;     /**      * Retrieves the number of values in this attribute.      *      * @return The nonnegative number of values in this attribute.      */    int size();     /**      * Retrieves the id of this attribute.      *      * @return The id of this attribute. It cannot be null.      */    String getID();     /**      * Determines whether a value is in the attribute.      * Equality is determined by the implementation, which may use      * <tt>Object.equals()</tt> or schema information to determine equality.      *      * @param attrVal The possibly null value to check. If null, check      *  whether the attribute has an attribute value whose value is null.      * @return true if attrVal is one of this attribute's values; false otherwise.      * @see java.lang.Object#equals      * @see BasicAttribute#equals      */    boolean contains(Object attrVal);    /**      * Adds a new value to the attribute.      * If the attribute values are unordered and      * <tt>attrVal</tt> is already in the attribute, this method does nothing.      * If the attribute values are ordered, <tt>attrVal</tt> is added to the end of      * the list of attribute values.      *<p>      * Equality is determined by the implementation, which may use      * <tt>Object.equals()</tt> or schema information to determine equality.      *      * @param attrVal The new possibly null value to add. If null, null      *  is added as an attribute value.      * @return true if a value was added; false otherwise.      */    boolean add(Object attrVal);     /**      * Removes a specified value from the attribute.      * If <tt>attrval</tt> is not in the attribute, this method does nothing.      * If the attribute values are ordered, the first occurrence of      * <tt>attrVal</tt> is removed and attribute values at indices greater      * than the removed      * value are shifted up towards the head of the list (and their indices      * decremented by one).      *<p>      * Equality is determined by the implementation, which may use      * <tt>Object.equals()</tt> or schema information to determine equality.      *      * @param attrval The possibly null value to remove from this attribute.      * If null, remove the attribute value that is null.      * @return true if the value was removed; false otherwise.      */    boolean remove(Object attrval);     /**      * Removes all values from this attribute.      */    void clear();     /**      * Retrieves the syntax definition associated with the attribute.      * An attribute's syntax definition specifies the format      * of the attribute's value(s). Note that this is different from      * the attribute value's representation as a Java object. Syntax      * definition refers to the directory's notion of <em>syntax</em>.      *<p>      * For example, even though a value might be      * a Java String object, its directory syntax might be "Printable String"      * or "Telephone Number". Or a value might be a byte array, and its      * directory syntax is "JPEG" or "Certificate".      * For example, if this attribute's syntax is "JPEG",      * this method would return the syntax definition for "JPEG".      * <p>      * The information that you can retrieve from a syntax definition      * is directory-dependent.      *<p>      * If an implementation does not support schemas, it should throw      * OperationNotSupportedException. If an implementation does support      * schemas, it should define this method to return the appropriate      * information.      * @return The attribute's syntax definition. Null if the implementation      *    supports schemas but this particular attribute does not have      *    any schema information.      * @exception OperationNotSupportedException If getting the schema      *         is not supported.      * @exception NamingException If a naming exception occurs while getting      *         the schema.      */     DirContext getAttributeSyntaxDefinition() throws NamingException;     /**      * Retrieves the attribute's schema definition.      * An attribute's schema definition contains information      * such as whether the attribute is multivalued or single-valued,      * the matching rules to use when comparing the attribute's values.      *      * The information that you can retrieve from an attribute definition      * is directory-dependent.      *      *<p>      * If an implementation does not support schemas, it should throw      * OperationNotSupportedException. If an implementation does support      * schemas, it should define this method to return the appropriate      * information.      * @return This attribute's schema definition. Null if the implementation      *     supports schemas but this particular attribute does not have      *     any schema information.      * @exception OperationNotSupportedException If getting the schema      *         is not supported.      * @exception NamingException If a naming exception occurs while getting      *         the schema.      */    DirContext getAttributeDefinition() throws NamingException;     /**      * Makes a copy of the attribute.      * The copy contains the same attribute values as the original attribute:      * the attribute values are not themselves cloned.      * Changes to the copy will not affect the original and vice versa.      *      * @return A non-null copy of the attribute.      */    Object clone();     //----------- Methods to support ordered multivalued attributes     /**      * Determines whether this attribute's values are ordered.      * If an attribute's values are ordered, duplicate values are allowed.      * If an attribute's values are unordered, they are presented      * in any order and there are no duplicate values.      * @return true if this attribute's values are ordered; false otherwise.      * @see #get(int)      * @see #remove(int)      * @see #add(int, java.lang.Object)      * @see #set(int, java.lang.Object)      */    boolean isOrdered();     /**     * Retrieves the attribute value from the ordered list of attribute values.     * This method returns the value at the <tt>ix</tt> index of the list of     * attribute values.     * If the attribute values are unordered,     * this method returns the value that happens to be at that index.     * @param ix The index of the value in the ordered list of attribute values.     * 0 <= <tt>ix</tt> < <tt>size()</tt>.     * @return The possibly null attribute value at index <tt>ix</tt>;     *   null if the attribute value is null.     * @exception NamingException If a naming exception was encountered while     * retrieving the value.     * @exception IndexOutOfBoundsException If <tt>ix</tt> is outside the specified range.     */    Object get(int ix) throws NamingException;     /**     * Removes an attribute value from the ordered list of attribute values.     * This method removes the value at the <tt>ix</tt> index of the list of     * attribute values.     * If the attribute values are unordered,     * this method removes the value that happens to be at that index.     * Values located at indices greater than <tt>ix</tt> are shifted up towards     * the front of the list (and their indices decremented by one).     *     * @param ix The index of the value to remove.     * 0 <= <tt>ix</tt> < <tt>size()</tt>.     * @return The possibly null attribute value at index <tt>ix</tt> that was removed;     *   null if the attribute value is null.     * @exception IndexOutOfBoundsException If <tt>ix</tt> is outside the specified range.     */    Object remove(int ix);     /**     * Adds an attribute value to the ordered list of attribute values.     * This method adds <tt>attrVal</tt> to the list of attribute values at     * index <tt>ix</tt>.     * Values located at indices at or greater than <tt>ix</tt> are     * shifted down towards the end of the list (and their indices incremented     * by one).     * If the attribute values are unordered and already have <tt>attrVal</tt>,     * <tt>IllegalStateException</tt> is thrown.     *     * @param ix The index in the ordered list of attribute values to add the new value.     * 0 <= <tt>ix</tt> <= <tt>size()</tt>.     * @param attrVal The possibly null attribute value to add; if null, null is     * the value added.     * @exception IndexOutOfBoundsException If <tt>ix</tt> is outside the specified range.     * @exception IllegalStateException If the attribute values are unordered and     * <tt>attrVal</tt> is one of those values.     */    void add(int ix, Object attrVal);      /**     * Sets an attribute value in the ordered list of attribute values.     * This method sets the value at the <tt>ix</tt> index of the list of     * attribute values to be <tt>attrVal</tt>. The old value is removed.     * If the attribute values are unordered,     * this method sets the value that happens to be at that index     * to <tt>attrVal</tt>, unless <tt>attrVal</tt> is already one of the values.     * In that case, <tt>IllegalStateException</tt> is thrown.     *     * @param ix The index of the value in the ordered list of attribute values.     * 0 <= <tt>ix</tt> < <tt>size()</tt>.     * @param attrVal The possibly null attribute value to use.     * If null, 'null' replaces the old value.     * @return The possibly null attribute value at index ix that was replaced.     *   Null if the attribute value was null.     * @exception IndexOutOfBoundsException If <tt>ix</tt> is outside the specified range.     * @exception IllegalStateException If <tt>attrVal</tt> already exists and the     *    attribute values are unordered.     */    Object set(int ix, Object attrVal);     /**     * Use serialVersionUID from JNDI 1.1.1 for interoperability.     */    static final long serialVersionUID = 8707690322213556804L;}