001 /* 002 * Copyright (C) 2012 eXo Platform SAS. 003 * 004 * This is free software; you can redistribute it and/or modify it 005 * under the terms of the GNU Lesser General Public License as 006 * published by the Free Software Foundation; either version 2.1 of 007 * the License, or (at your option) any later version. 008 * 009 * This software is distributed in the hope that it will be useful, 010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 012 * Lesser General Public License for more details. 013 * 014 * You should have received a copy of the GNU Lesser General Public 015 * License along with this software; if not, write to the Free 016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 018 */ 019 020 package org.crsh.util; 021 022 import java.io.Closeable; 023 import java.util.ArrayList; 024 import java.util.concurrent.atomic.AtomicBoolean; 025 import java.util.logging.Level; 026 import java.util.logging.Logger; 027 028 public final class CloseableList implements Closeable { 029 030 /** . */ 031 final Logger log = Logger.getLogger(CloseableList.class.getName()); 032 033 /** . */ 034 private final ArrayList<Closeable> closeables; 035 036 /** . */ 037 private final AtomicBoolean closed; 038 039 public CloseableList() { 040 this.closeables = new ArrayList<Closeable>(); 041 this.closed = new AtomicBoolean(false); 042 } 043 044 public boolean isClosed() { 045 return closed.get(); 046 } 047 048 /** 049 * Add a closeable to the list. 050 * 051 * @param closeable the closeable to add 052 * @throws IllegalStateException if the list is already closed 053 * @throws NullPointerException if the argument is null 054 */ 055 public void add(Closeable closeable) throws IllegalStateException, NullPointerException { 056 if (closed.get()) { 057 throw new IllegalStateException("Already closed"); 058 } 059 if (closeable == null) { 060 throw new NullPointerException("No null closeable accepted"); 061 } 062 if (!closeables.contains(closeable)) { 063 closeables.add(closeable); 064 } 065 } 066 067 public void close() { 068 if (closed.compareAndSet(false, true)) { 069 for (Closeable closeable : closeables) { 070 log.log(Level.FINE, "Closing " + closeable.getClass().getSimpleName()); 071 Safe.close(closeable); 072 } 073 } 074 } 075 }