1 /*

     2  * Copyright 2007-2009 Sun Microsystems, Inc.  All Rights Reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Sun designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Sun in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

    22  * CA 95054 USA or visit www.sun.com if you need additional information or

    23  * have any questions.

    24  */

    25 

    26 package java.nio.file.attribute;

    27 

    28 import java.util.*;

    29 import java.io.IOException;

    30 

    31 /**

    32  * An object that provides a read-only or updatable <em>view</em> of non-opaque

    33  * values associated with an object in a filesystem. This interface is extended

    34  * or implemented by specific attribute views that define the attributes

    35  * supported by the view. A specific attribute view will typically define

    36  * type-safe methods to read or update the attributes that it supports. It also

    37  * provides <em>dynamic access</em> where the {@link #readAttributes

    38  * readAttributes}, {@link #getAttribute getAttribute} and {@link #setAttribute

    39  * setAttributs} methods are used to access the attributes by names defined

    40  * by the attribute view. Implementations must ensure that the attribute names

    41  * do not contain the colon (':') or comma (',') characters.

    42  *

    43  * @since 1.7

    44  */

    45 

    46 public interface AttributeView {

    47     /**

    48      * Returns the name of the attribute view.

    49      */

    50     String name();

    51 

    52     /**

    53      * Reads the value of an attribute.

    54      *

    55      * @param   attribute

    56      *          The attribute name (case sensitive)

    57      *

    58      * @return  The value of the attribute, or {@code null} if the attribute is

    59      *          not supported

    60      *

    61      * @throws  IOException

    62      *          If an I/O error occurs

    63      * @throws  SecurityException

    64      *          If a security manager is set and it denies access

    65      */

    66     Object getAttribute(String attribute) throws IOException;

    67 

    68     /**

    69      * Sets/updates the value of an attribute.

    70      *

    71      * @param   attribute

    72      *          The attribute name (case sensitive)

    73      * @param   value

    74      *          The attribute value

    75      *

    76      * @throws  UnsupportedOperationException

    77      *          If the attribute is not supported or this attribute view does

    78      *          not support updating the value of the attribute

    79      * @throws  IllegalArgumentException

    80      *          If the attribute value is of the correct type but has an

    81      *          inappropriate value

    82      * @throws  ClassCastException

    83      *          If the attribute value is not of the expected type or is a

    84      *          collection containing elements that are not of the expected

    85      *          type

    86      * @throws  IOException

    87      *          If an I/O error occurs

    88      * @throws  SecurityException

    89      *          If a security manager is set and it denies access

    90      */

    91     void setAttribute(String attribute, Object value) throws IOException;

    92 

    93     /**

    94      * Reads all, or a subset, of the attributes supported by this file attribute

    95      * view.

    96      *

    97      * <p> The {@code first} and {@code rest} parameters are the names of the

    98      * attributes to read. If any of the parameters has the value {@code "*"}

    99      * then all attributes are read. Attributes that are not supported are

   100      * ignored and will not be present in the returned map. It is implementation

   101      * specific if all attributes are read as an atomic operation with respect

   102      * to other file system operations.

   103      *

   104      * @param   first

   105      *          The name of an attribute to read (case sensitive)

   106      * @param   rest

   107      *          The names of others attributes to read (case sensitive)

   108      *

   109      * @return  An unmodifiable map of the attributes; may be empty. Its keys are

   110      *          the attribute names, its values are the attribute values

   111      *

   112      * @throws  IOException

   113      *          If an I/O error occurs

   114      * @throws  SecurityException

   115      *          If a security manager is set and it denies access

   116      */

   117     Map<String,?> readAttributes(String first, String... rest) throws IOException;

   118 }