1 /* 2 * Copyright (c) 2014, 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 package jdk.internal.jrtfs; 26 27 import java.nio.file.DirectoryStream; 28 import java.nio.file.ClosedDirectoryStreamException; 29 import java.nio.file.DirectoryIteratorException; 30 import java.nio.file.NotDirectoryException; 31 import java.nio.file.Path; 32 import java.util.Iterator; 33 import java.util.Objects; 34 import java.util.NoSuchElementException; 35 import java.io.IOException; 36 37 /** 38 * DirectoryStream implementation for jrt file system implementations. 39 * 40 * @implNote This class needs to maintain JDK 8 source compatibility. 41 * 42 * It is used internally in the JDK to implement jimage/jrtfs access, 43 * but also compiled and delivered as part of the jrtfs.jar to support access 44 * to the jimage file provided by the shipped JDK by tools running on JDK 8. 45 */ 46 final class JrtDirectoryStream implements DirectoryStream<Path> { 47 48 private final JrtPath dir; 49 private final DirectoryStream.Filter<? super Path> filter; 50 private volatile boolean isClosed; 51 private volatile Iterator<Path> itr; 52 53 JrtDirectoryStream(JrtPath dir, 54 DirectoryStream.Filter<? super java.nio.file.Path> filter) 55 throws IOException 56 { 57 this.dir = dir; 58 if (!dir.jrtfs.isDirectory(dir, true)) { // sanity check 59 throw new NotDirectoryException(dir.toString()); 60 } 61 this.filter = filter; 62 } 63 64 @Override 65 public synchronized Iterator<Path> iterator() { 66 if (isClosed) 67 throw new ClosedDirectoryStreamException(); 68 if (itr != null) 69 throw new IllegalStateException("Iterator has already been returned"); 70 try { 71 itr = dir.jrtfs.iteratorOf(dir, filter); 72 } catch (IOException e) { 73 throw new IllegalStateException(e); 74 } 75 return new Iterator<Path>() { 76 private Path next; 77 @Override 78 public synchronized boolean hasNext() { 79 if (isClosed) 80 return false; 81 return itr.hasNext(); 82 } 83 84 @Override 85 public synchronized Path next() { 86 if (isClosed) 87 throw new NoSuchElementException(); 88 return itr.next(); 89 } 90 91 @Override 92 public void remove() { 93 throw new UnsupportedOperationException(); 94 } 95 }; 96 } 97 98 @Override 99 public synchronized void close() throws IOException { 100 isClosed = true; 101 } 102 }