src/java.base/share/classes/java/io/DeleteOnExitHook.java

*** 1,7 ****
  /*
!  * Copyright (c) 2005, 2018, 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
--- 1,7 ----
  /*
!  * Copyright (c) 2005, 2019, 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
*** 33,43 ****
   * A set is used both to prevent double-insertion of the same file as well as offer
   * quick removal.
   */
  
  class DeleteOnExitHook {
!     private static LinkedHashSet<String> files = new LinkedHashSet<>();
      static {
          // DeleteOnExitHook must be the last shutdown hook to be invoked.
          // Application shutdown hooks may add the first file to the
          // delete on exit list and cause the DeleteOnExitHook to be
          // registered during shutdown in progress. So set the
--- 33,43 ----
   * A set is used both to prevent double-insertion of the same file as well as offer
   * quick removal.
   */
  
  class DeleteOnExitHook {
!     private static LinkedHashMap<String, int[]> files = new LinkedHashMap<>();
      static {
          // DeleteOnExitHook must be the last shutdown hook to be invoked.
          // Application shutdown hooks may add the first file to the
          // delete on exit list and cause the DeleteOnExitHook to be
          // registered during shutdown in progress. So set the
*** 59,80 ****
          if(files == null) {
              // DeleteOnExitHook is running. Too late to add a file
              throw new IllegalStateException("Shutdown in progress");
          }
  
!         files.add(file);
      }
  
      static void runHooks() {
!         LinkedHashSet<String> theFiles;
  
          synchronized (DeleteOnExitHook.class) {
              theFiles = files;
              files = null;
          }
  
!         ArrayList<String> toBeDeleted = new ArrayList<>(theFiles);
  
          // reverse the list to maintain previous jdk deletion order.
          // Last in first deleted.
          Collections.reverse(toBeDeleted);
          for (String filename : toBeDeleted) {
--- 59,86 ----
          if(files == null) {
              // DeleteOnExitHook is running. Too late to add a file
              throw new IllegalStateException("Shutdown in progress");
          }
  
!         files.computeIfAbsent(file, f -> new int[1])[0]++;
!     }
! 
!     static synchronized void remove(String file) {
!         if(files != null) {
!             files.computeIfPresent(file, (f, count) -> --count[0] <= 0 ? null : count);
!         }
      }
  
      static void runHooks() {
!         LinkedHashMap<String, int[]> theFiles;
  
          synchronized (DeleteOnExitHook.class) {
              theFiles = files;
              files = null;
          }
  
!         ArrayList<String> toBeDeleted = new ArrayList<>(theFiles.keySet());
  
          // reverse the list to maintain previous jdk deletion order.
          // Last in first deleted.
          Collections.reverse(toBeDeleted);
          for (String filename : toBeDeleted) {