1 /*
   2  * Copyright (c) 2010, 2011, Oracle and/or its affiliates. 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.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package java.nio.file;
  27 
  28 import java.util.ConcurrentModificationException;
  29 import java.util.Objects;
  30 import java.io.IOException;
  31 import java.io.ObjectInputStream;
  32 import java.io.InvalidObjectException;
  33 
  34 /**
  35  * Runtime exception thrown if an I/O error is encountered when iterating over
  36  * the entries in a directory. The I/O error is retrieved as an {@link
  37  * IOException} using the {@link #getCause() getCause()} method.
  38  *
  39  * @since 1.7
  40  * @see DirectoryStream
  41  */
  42 
  43 public final class DirectoryIteratorException
  44     extends ConcurrentModificationException
  45 {
  46     private static final long serialVersionUID = -6012699886086212874L;
  47 
  48     /**
  49      * Constructs an instance of this class.
  50      *
  51      * @param   cause
  52      *          the {@code IOException} that caused the directory iteration
  53      *          to fail
  54      *
  55      * @throws  NullPointerException
  56      *          if the cause is {@code null}
  57      */
  58     public DirectoryIteratorException(IOException cause) {
  59         super(Objects.requireNonNull(cause));
  60     }
  61 
  62     /**
  63      * Returns the cause of this exception.
  64      *
  65      * @return  the cause
  66      */
  67     @Override
  68     public IOException getCause() {
  69         return (IOException)super.getCause();
  70     }
  71 
  72     /**
  73      * Called to read the object from a stream.
  74      *
  75      * @throws  InvalidObjectException
  76      *          if the object is invalid or has a cause that is not
  77      *          an {@code IOException}
  78      */
  79     private void readObject(ObjectInputStream s)
  80         throws IOException, ClassNotFoundException
  81     {
  82         s.defaultReadObject();
  83         Throwable cause = super.getCause();
  84         if (!(cause instanceof IOException))
  85             throw new InvalidObjectException("Cause must be an IOException");
  86     }
  87 }