1 /*

     2  * Copyright (c) 2019, 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 jdk.jfr.internal;

    27 

    28 import java.io.IOException;

    29 import java.util.ArrayList;

    30 import java.util.LinkedHashSet;

    31 import java.util.Set;

    32 

    33 import jdk.jfr.internal.SecuritySupport.SafePath;

    34 

    35 // This class keeps track of files that can't be deleted

    36 // so they can a later staged be removed.

    37 final class FilePurger {

    38 

    39     private final static Set<SafePath> paths = new LinkedHashSet<>();

    40 

    41     public synchronized static void add(SafePath p) {

    42         paths.add(p);

    43         if (paths.size() > 1000) {

    44             removeOldest();

    45         }

    46     }

    47 

    48     public synchronized static void purge() {

    49         if (paths.isEmpty()) {

    50             return;

    51         }

    52 

    53         for (SafePath p : new ArrayList<>(paths)) {

    54             if (delete(p)) {

    55                 paths.remove(p);

    56             }

    57         }

    58     }

    59 

    60     private static void removeOldest() {

    61         SafePath oldest = paths.iterator().next();

    62         paths.remove(oldest);

    63     }

    64 

    65     private static boolean delete(SafePath p) {

    66         try {

    67             SecuritySupport.delete(p);

    68             return true;

    69         } catch (IOException e) {

    70             return false;

    71         }

    72     }

    73 }