src/jdk.zipfs/share/classes/jdk/nio/zipfs/ZipPath.java
changeset 47216 71c04702a3d5
parent 46901 f63587417ae6
child 53043 fd2e8f941ded
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.zipfs/share/classes/jdk/nio/zipfs/ZipPath.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,992 @@
+/*
+ * Copyright (c) 2009, 2017, 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
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.nio.zipfs;
+
+import java.io.*;
+import java.net.URI;
+import java.nio.channels.*;
+import java.nio.file.*;
+import java.nio.file.DirectoryStream.Filter;
+import java.nio.file.attribute.*;
+import java.util.*;
+import static java.nio.charset.StandardCharsets.UTF_8;
+import static java.nio.file.StandardOpenOption.*;
+import static java.nio.file.StandardCopyOption.*;
+
+/**
+ *
+ * @author  Xueming Shen, Rajendra Gutupalli,Jaya Hangal
+ */
+
+final class ZipPath implements Path {
+
+    private final ZipFileSystem zfs;
+    private final byte[] path;
+    private volatile int[] offsets;
+    private int hashcode = 0;  // cached hashcode (created lazily)
+
+    ZipPath(ZipFileSystem zfs, byte[] path) {
+        this(zfs, path, false);
+    }
+
+    ZipPath(ZipFileSystem zfs, byte[] path, boolean normalized) {
+        this.zfs = zfs;
+        if (normalized) {
+            this.path = path;
+        } else {
+            if (zfs.zc.isUTF8()) {
+                this.path = normalize(path);
+            } else {    // see normalize(String);
+                this.path = normalize(zfs.getString(path));
+            }
+        }
+    }
+
+    ZipPath(ZipFileSystem zfs, String path) {
+        this.zfs = zfs;
+        this.path = normalize(path);
+    }
+
+    @Override
+    public ZipPath getRoot() {
+        if (this.isAbsolute())
+            return zfs.getRootDir();
+        else
+            return null;
+    }
+
+   @Override
+    public Path getFileName() {
+        int off = path.length;
+        if (off == 0 || off == 1 && path[0] == '/')
+            return null;
+        while (--off >= 0 && path[off] != '/') {}
+        if (off < 0)
+            return this;
+        off++;
+        byte[] result = new byte[path.length - off];
+        System.arraycopy(path, off, result, 0, result.length);
+        return new ZipPath(getFileSystem(), result, true);
+    }
+
+    @Override
+    public ZipPath getParent() {
+        int off = path.length;
+        if (off == 0 || off == 1 && path[0] == '/')
+            return null;
+        while (--off >= 0 && path[off] != '/') {}
+        if (off <= 0)
+            return getRoot();
+        byte[] result = new byte[off];
+        System.arraycopy(path, 0, result, 0, off);
+        return new ZipPath(getFileSystem(), result, true);
+    }
+
+    @Override
+    public int getNameCount() {
+        initOffsets();
+        return offsets.length;
+    }
+
+    @Override
+    public ZipPath getName(int index) {
+        initOffsets();
+        if (index < 0 || index >= offsets.length)
+            throw new IllegalArgumentException();
+        int begin = offsets[index];
+        int len;
+        if (index == (offsets.length-1))
+            len = path.length - begin;
+        else
+            len = offsets[index+1] - begin - 1;
+        // construct result
+        byte[] result = new byte[len];
+        System.arraycopy(path, begin, result, 0, len);
+        return new ZipPath(zfs, result);
+    }
+
+    @Override
+    public ZipPath subpath(int beginIndex, int endIndex) {
+        initOffsets();
+        if (beginIndex < 0 ||
+            beginIndex >=  offsets.length ||
+            endIndex > offsets.length ||
+            beginIndex >= endIndex)
+            throw new IllegalArgumentException();
+
+        // starting offset and length
+        int begin = offsets[beginIndex];
+        int len;
+        if (endIndex == offsets.length)
+            len = path.length - begin;
+        else
+            len = offsets[endIndex] - begin - 1;
+        // construct result
+        byte[] result = new byte[len];
+        System.arraycopy(path, begin, result, 0, len);
+        return new ZipPath(zfs, result);
+    }
+
+    @Override
+    public ZipPath toRealPath(LinkOption... options) throws IOException {
+        ZipPath realPath;
+        byte[] resolved = getResolvedPath();
+        // resolved is always absolute and normalized
+        if (resolved == path) {
+            realPath = this;
+        } else {
+            realPath = new ZipPath(zfs, resolved, true);
+            realPath.resolved = resolved;
+        }
+        realPath.checkAccess();
+        return realPath;
+    }
+
+    boolean isHidden() {
+        return false;
+    }
+
+    @Override
+    public ZipPath toAbsolutePath() {
+        if (isAbsolute()) {
+            return this;
+        } else {
+            // add '/' before the existing path
+            byte[] tmp = new byte[path.length + 1];
+            System.arraycopy(path, 0, tmp, 1, path.length);
+            tmp[0] = '/';
+            return new ZipPath(zfs, tmp, true);  // normalized
+        }
+    }
+
+    @Override
+    public URI toUri() {
+        try {
+            return new URI("jar",
+                           decodeUri(zfs.getZipFile().toUri().toString()) +
+                           "!" +
+                           zfs.getString(toAbsolutePath().path),
+                           null);
+        } catch (Exception ex) {
+            throw new AssertionError(ex);
+        }
+    }
+
+    private boolean equalsNameAt(ZipPath other, int index) {
+        int mbegin = offsets[index];
+        int mlen = 0;
+        if (index == (offsets.length-1))
+            mlen = path.length - mbegin;
+        else
+            mlen = offsets[index + 1] - mbegin - 1;
+        int obegin = other.offsets[index];
+        int olen = 0;
+        if (index == (other.offsets.length - 1))
+            olen = other.path.length - obegin;
+        else
+            olen = other.offsets[index + 1] - obegin - 1;
+        if (mlen != olen)
+            return false;
+        int n = 0;
+        while(n < mlen) {
+            if (path[mbegin + n] != other.path[obegin + n])
+                return false;
+            n++;
+        }
+        return true;
+    }
+
+    @Override
+    public Path relativize(Path other) {
+        final ZipPath o = checkPath(other);
+        if (o.equals(this))
+            return new ZipPath(zfs, new byte[0], true);
+        if (this.path.length == 0)
+            return o;
+        if (this.zfs != o.zfs || this.isAbsolute() != o.isAbsolute())
+            throw new IllegalArgumentException();
+        if (this.path.length == 1 && this.path[0] == '/')
+            return new ZipPath(zfs,
+                               Arrays.copyOfRange(o.path, 1, o.path.length),
+                               true);
+        int mc = this.getNameCount();
+        int oc = o.getNameCount();
+        int n = Math.min(mc, oc);
+        int i = 0;
+        while (i < n) {
+            if (!equalsNameAt(o, i))
+                break;
+            i++;
+        }
+        int dotdots = mc - i;
+        int len = dotdots * 3 - 1;
+        if (i < oc)
+            len += (o.path.length - o.offsets[i] + 1);
+        byte[] result = new byte[len];
+
+        int pos = 0;
+        while (dotdots > 0) {
+            result[pos++] = (byte)'.';
+            result[pos++] = (byte)'.';
+            if (pos < len)       // no tailing slash at the end
+                result[pos++] = (byte)'/';
+            dotdots--;
+        }
+        if (i < oc)
+            System.arraycopy(o.path, o.offsets[i],
+                             result, pos,
+                             o.path.length - o.offsets[i]);
+        return new ZipPath(zfs, result);
+    }
+
+    @Override
+    public ZipFileSystem getFileSystem() {
+        return zfs;
+    }
+
+    @Override
+    public boolean isAbsolute() {
+        return path.length > 0 && path[0] == '/';
+    }
+
+    @Override
+    public ZipPath resolve(Path other) {
+        ZipPath o = checkPath(other);
+        if (o.path.length == 0)
+            return this;
+        if (o.isAbsolute() || this.path.length == 0)
+            return o;
+        return resolve(o.path);
+    }
+
+    // opath is normalized, just concat
+    private ZipPath resolve(byte[] opath) {
+        byte[] resolved = null;
+        byte[] tpath = this.path;
+        int tlen = tpath.length;
+        int olen = opath.length;
+        if (path[tlen - 1] == '/') {
+            resolved = new byte[tlen + olen];
+            System.arraycopy(tpath, 0, resolved, 0, tlen);
+            System.arraycopy(opath, 0, resolved, tlen, olen);
+        } else {
+            resolved = new byte[tlen + 1 + olen];
+            System.arraycopy(tpath, 0, resolved, 0, tlen);
+            resolved[tlen] = '/';
+            System.arraycopy(opath, 0, resolved, tlen + 1, olen);
+        }
+        return new ZipPath(zfs, resolved, true);
+    }
+
+    @Override
+    public Path resolveSibling(Path other) {
+        Objects.requireNonNull(other, "other");
+        Path parent = getParent();
+        return (parent == null) ? other : parent.resolve(other);
+    }
+
+    @Override
+    public boolean startsWith(Path other) {
+        Objects.requireNonNull(other, "other");
+        if (!(other instanceof ZipPath))
+            return false;
+        final ZipPath o = (ZipPath)other;
+        if (o.isAbsolute() != this.isAbsolute() ||
+            o.path.length > this.path.length)
+            return false;
+        int olast = o.path.length;
+        for (int i = 0; i < olast; i++) {
+            if (o.path[i] != this.path[i])
+                return false;
+        }
+        olast--;
+        return o.path.length == this.path.length ||
+               o.path[olast] == '/' ||
+               this.path[olast + 1] == '/';
+    }
+
+    @Override
+    public boolean endsWith(Path other) {
+        Objects.requireNonNull(other, "other");
+        if (!(other instanceof ZipPath))
+            return false;
+        final ZipPath o = (ZipPath)other;
+        int olast = o.path.length - 1;
+        if (olast > 0 && o.path[olast] == '/')
+            olast--;
+        int last = this.path.length - 1;
+        if (last > 0 && this.path[last] == '/')
+            last--;
+        if (olast == -1)    // o.path.length == 0
+            return last == -1;
+        if ((o.isAbsolute() &&(!this.isAbsolute() || olast != last)) ||
+            (last < olast))
+            return false;
+        for (; olast >= 0; olast--, last--) {
+            if (o.path[olast] != this.path[last])
+                return false;
+        }
+        return o.path[olast + 1] == '/' ||
+               last == -1 || this.path[last] == '/';
+    }
+
+    @Override
+    public ZipPath resolve(String other) {
+        byte[] opath = normalize(other);
+        if (opath.length == 0)
+            return this;
+        if (opath[0] == '/' || this.path.length == 0)
+            return new ZipPath(zfs, opath, true);
+        return resolve(opath);
+    }
+
+    @Override
+    public final Path resolveSibling(String other) {
+        return resolveSibling(zfs.getPath(other));
+    }
+
+    @Override
+    public final boolean startsWith(String other) {
+        return startsWith(zfs.getPath(other));
+    }
+
+    @Override
+    public final boolean endsWith(String other) {
+        return endsWith(zfs.getPath(other));
+    }
+
+    @Override
+    public Path normalize() {
+        byte[] resolved = getResolved();
+        if (resolved == path)    // no change
+            return this;
+        return new ZipPath(zfs, resolved, true);
+    }
+
+    private ZipPath checkPath(Path path) {
+        Objects.requireNonNull(path, "path");
+        if (!(path instanceof ZipPath))
+            throw new ProviderMismatchException();
+        return (ZipPath) path;
+    }
+
+    // create offset list if not already created
+    private void initOffsets() {
+        if (offsets == null) {
+            int count, index;
+            // count names
+            count = 0;
+            index = 0;
+            if (path.length == 0) {
+                // empty path has one name
+                count = 1;
+            } else {
+                while (index < path.length) {
+                    byte c = path[index++];
+                    if (c != '/') {
+                        count++;
+                        while (index < path.length && path[index] != '/')
+                             index++;
+                    }
+                }
+            }
+            // populate offsets
+            int[] result = new int[count];
+            count = 0;
+            index = 0;
+            while (index < path.length) {
+                byte c = path[index];
+                if (c == '/') {
+                    index++;
+                } else {
+                    result[count++] = index++;
+                    while (index < path.length && path[index] != '/')
+                        index++;
+                }
+            }
+            synchronized (this) {
+                if (offsets == null)
+                    offsets = result;
+            }
+        }
+    }
+
+    // resolved path for locating zip entry inside the zip file,
+    // the result path does not contain ./ and .. components
+    private volatile byte[] resolved = null;
+    byte[] getResolvedPath() {
+        byte[] r = resolved;
+        if (r == null) {
+            if (isAbsolute())
+                r = getResolved();
+            else
+                r = toAbsolutePath().getResolvedPath();
+            resolved = r;
+        }
+        return resolved;
+    }
+
+    // removes redundant slashs, replace "\" to zip separator "/"
+    // and check for invalid characters
+    private byte[] normalize(byte[] path) {
+        int len = path.length;
+        if (len == 0)
+            return path;
+        byte prevC = 0;
+        for (int i = 0; i < len; i++) {
+            byte c = path[i];
+            if (c == '\\' || c == '\u0000')
+                return normalize(path, i);
+            if (c == (byte)'/' && prevC == '/')
+                return normalize(path, i - 1);
+            prevC = c;
+        }
+        if (len > 1 && prevC == '/') {
+            return Arrays.copyOf(path, len - 1);
+        }
+        return path;
+    }
+
+    private byte[] normalize(byte[] path, int off) {
+        byte[] to = new byte[path.length];
+        int n = 0;
+        while (n < off) {
+            to[n] = path[n];
+            n++;
+        }
+        int m = n;
+        byte prevC = 0;
+        while (n < path.length) {
+            byte c = path[n++];
+            if (c == (byte)'\\')
+                c = (byte)'/';
+            if (c == (byte)'/' && prevC == (byte)'/')
+                continue;
+            if (c == '\u0000')
+                throw new InvalidPathException(zfs.getString(path),
+                                               "Path: nul character not allowed");
+            to[m++] = c;
+            prevC = c;
+        }
+        if (m > 1 && to[m - 1] == '/')
+            m--;
+        return (m == to.length)? to : Arrays.copyOf(to, m);
+    }
+
+    // if zfs is NOT in utf8, normalize the path as "String"
+    // to avoid incorrectly normalizing byte '0x5c' (as '\')
+    // to '/'.
+    private byte[] normalize(String path) {
+        if (zfs.zc.isUTF8())
+            return normalize(zfs.getBytes(path));
+        int len = path.length();
+        if (len == 0)
+            return new byte[0];
+        char prevC = 0;
+        for (int i = 0; i < len; i++) {
+            char c = path.charAt(i);
+            if (c == '\\' || c == '\u0000')
+                return normalize(path, i, len);
+            if (c == '/' && prevC == '/')
+                return normalize(path, i - 1, len);
+            prevC = c;
+        }
+        if (len > 1 && prevC == '/')
+            path = path.substring(0, len - 1);
+        return zfs.getBytes(path);
+    }
+
+    private byte[] normalize(String path, int off, int len) {
+        StringBuilder to = new StringBuilder(len);
+        to.append(path, 0, off);
+        int m = off;
+        char prevC = 0;
+        while (off < len) {
+            char c = path.charAt(off++);
+            if (c == '\\')
+                c = '/';
+            if (c == '/' && prevC == '/')
+                continue;
+            if (c == '\u0000')
+                throw new InvalidPathException(path,
+                                               "Path: nul character not allowed");
+            to.append(c);
+            prevC = c;
+        }
+        len = to.length();
+        if (len > 1 && prevC == '/')
+            to.delete(len -1, len);
+        return zfs.getBytes(to.toString());
+    }
+
+    // Remove DotSlash(./) and resolve DotDot (..) components
+    private byte[] getResolved() {
+        for (int i = 0; i < path.length; i++) {
+            if (path[i] == (byte)'.' &&
+                (i + 1 == path.length || path[i + 1] == '/')) {
+                return resolve0();
+            }
+        }
+        return path;
+    }
+
+    // TBD: performance, avoid initOffsets
+    private byte[] resolve0() {
+        byte[] to = new byte[path.length];
+        int nc = getNameCount();
+        int[] lastM = new int[nc];
+        int lastMOff = -1;
+        int m = 0;
+        for (int i = 0; i < nc; i++) {
+            int n = offsets[i];
+            int len = (i == offsets.length - 1)?
+                      (path.length - n):(offsets[i + 1] - n - 1);
+            if (len == 1 && path[n] == (byte)'.') {
+                if (m == 0 && path[0] == '/')   // absolute path
+                    to[m++] = '/';
+                continue;
+            }
+            if (len == 2 && path[n] == '.' && path[n + 1] == '.') {
+                if (lastMOff >= 0) {
+                    m = lastM[lastMOff--];  // retreat
+                    continue;
+                }
+                if (path[0] == '/') {  // "/../xyz" skip
+                    if (m == 0)
+                        to[m++] = '/';
+                } else {               // "../xyz" -> "../xyz"
+                    if (m != 0 && to[m-1] != '/')
+                        to[m++] = '/';
+                    while (len-- > 0)
+                        to[m++] = path[n++];
+                }
+                continue;
+            }
+            if (m == 0 && path[0] == '/' ||   // absolute path
+                m != 0 && to[m-1] != '/') {   // not the first name
+                to[m++] = '/';
+            }
+            lastM[++lastMOff] = m;
+            while (len-- > 0)
+                to[m++] = path[n++];
+        }
+        if (m > 1 && to[m - 1] == '/')
+            m--;
+        return (m == to.length)? to : Arrays.copyOf(to, m);
+    }
+
+    @Override
+    public String toString() {
+        return zfs.getString(path);
+    }
+
+    @Override
+    public int hashCode() {
+        int h = hashcode;
+        if (h == 0)
+            hashcode = h = Arrays.hashCode(path);
+        return h;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        return obj != null &&
+               obj instanceof ZipPath &&
+               this.zfs == ((ZipPath)obj).zfs &&
+               compareTo((Path) obj) == 0;
+    }
+
+    @Override
+    public int compareTo(Path other) {
+        final ZipPath o = checkPath(other);
+        int len1 = this.path.length;
+        int len2 = o.path.length;
+
+        int n = Math.min(len1, len2);
+        byte v1[] = this.path;
+        byte v2[] = o.path;
+
+        int k = 0;
+        while (k < n) {
+            int c1 = v1[k] & 0xff;
+            int c2 = v2[k] & 0xff;
+            if (c1 != c2)
+                return c1 - c2;
+            k++;
+        }
+        return len1 - len2;
+    }
+
+    public WatchKey register(
+            WatchService watcher,
+            WatchEvent.Kind<?>[] events,
+            WatchEvent.Modifier... modifiers) {
+        if (watcher == null || events == null || modifiers == null) {
+            throw new NullPointerException();
+        }
+        // watcher must be associated with a different provider
+        throw new ProviderMismatchException();
+    }
+
+    @Override
+    public WatchKey register(WatchService watcher, WatchEvent.Kind<?>... events) {
+        return register(watcher, events, new WatchEvent.Modifier[0]);
+    }
+
+    @Override
+    public final File toFile() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public Iterator<Path> iterator() {
+        return new Iterator<Path>() {
+            private int i = 0;
+
+            @Override
+            public boolean hasNext() {
+                return (i < getNameCount());
+            }
+
+            @Override
+            public Path next() {
+                if (i < getNameCount()) {
+                    Path result = getName(i);
+                    i++;
+                    return result;
+                } else {
+                    throw new NoSuchElementException();
+                }
+            }
+
+            @Override
+            public void remove() {
+                throw new ReadOnlyFileSystemException();
+            }
+        };
+    }
+
+    /////////////////////////////////////////////////////////////////////
+
+    void createDirectory(FileAttribute<?>... attrs)
+        throws IOException
+    {
+        zfs.createDirectory(getResolvedPath(), attrs);
+    }
+
+    InputStream newInputStream(OpenOption... options) throws IOException
+    {
+        if (options.length > 0) {
+            for (OpenOption opt : options) {
+                if (opt != READ)
+                    throw new UnsupportedOperationException("'" + opt + "' not allowed");
+            }
+        }
+        return zfs.newInputStream(getResolvedPath());
+    }
+
+    DirectoryStream<Path> newDirectoryStream(Filter<? super Path> filter)
+        throws IOException
+    {
+        return new ZipDirectoryStream(this, filter);
+    }
+
+    void delete() throws IOException {
+        zfs.deleteFile(getResolvedPath(), true);
+    }
+
+    void deleteIfExists() throws IOException {
+        zfs.deleteFile(getResolvedPath(), false);
+    }
+
+    ZipFileAttributes getAttributes() throws IOException
+    {
+        ZipFileAttributes zfas = zfs.getFileAttributes(getResolvedPath());
+        if (zfas == null)
+            throw new NoSuchFileException(toString());
+        return zfas;
+    }
+
+    void setAttribute(String attribute, Object value, LinkOption... options)
+        throws IOException
+    {
+        String type = null;
+        String attr = null;
+        int colonPos = attribute.indexOf(':');
+        if (colonPos == -1) {
+            type = "basic";
+            attr = attribute;
+        } else {
+            type = attribute.substring(0, colonPos++);
+            attr = attribute.substring(colonPos);
+        }
+        ZipFileAttributeView view = ZipFileAttributeView.get(this, type);
+        if (view == null)
+            throw new UnsupportedOperationException("view <" + view + "> is not supported");
+        view.setAttribute(attr, value);
+    }
+
+    void setTimes(FileTime mtime, FileTime atime, FileTime ctime)
+        throws IOException
+    {
+        zfs.setTimes(getResolvedPath(), mtime, atime, ctime);
+    }
+
+    Map<String, Object> readAttributes(String attributes, LinkOption... options)
+        throws IOException
+
+    {
+        String view = null;
+        String attrs = null;
+        int colonPos = attributes.indexOf(':');
+        if (colonPos == -1) {
+            view = "basic";
+            attrs = attributes;
+        } else {
+            view = attributes.substring(0, colonPos++);
+            attrs = attributes.substring(colonPos);
+        }
+        ZipFileAttributeView zfv = ZipFileAttributeView.get(this, view);
+        if (zfv == null) {
+            throw new UnsupportedOperationException("view not supported");
+        }
+        return zfv.readAttributes(attrs);
+    }
+
+    FileStore getFileStore() throws IOException {
+        // each ZipFileSystem only has one root (as requested for now)
+        if (exists())
+            return zfs.getFileStore(this);
+        throw new NoSuchFileException(zfs.getString(path));
+    }
+
+    boolean isSameFile(Path other) throws IOException {
+        if (this.equals(other))
+            return true;
+        if (other == null ||
+            this.getFileSystem() != other.getFileSystem())
+            return false;
+        this.checkAccess();
+        ((ZipPath)other).checkAccess();
+        return Arrays.equals(this.getResolvedPath(),
+                             ((ZipPath)other).getResolvedPath());
+    }
+
+    SeekableByteChannel newByteChannel(Set<? extends OpenOption> options,
+                                       FileAttribute<?>... attrs)
+        throws IOException
+    {
+        return zfs.newByteChannel(getResolvedPath(), options, attrs);
+    }
+
+
+    FileChannel newFileChannel(Set<? extends OpenOption> options,
+                               FileAttribute<?>... attrs)
+        throws IOException
+    {
+        return zfs.newFileChannel(getResolvedPath(), options, attrs);
+    }
+
+    void checkAccess(AccessMode... modes) throws IOException {
+        boolean w = false;
+        boolean x = false;
+        for (AccessMode mode : modes) {
+            switch (mode) {
+                case READ:
+                    break;
+                case WRITE:
+                    w = true;
+                    break;
+                case EXECUTE:
+                    x = true;
+                    break;
+                default:
+                    throw new UnsupportedOperationException();
+            }
+        }
+        zfs.checkAccess(getResolvedPath());
+        if ((w && zfs.isReadOnly()) || x) {
+            throw new AccessDeniedException(toString());
+        }
+    }
+
+    boolean exists() {
+        try {
+            return zfs.exists(getResolvedPath());
+        } catch (IOException x) {}
+        return false;
+    }
+
+    OutputStream newOutputStream(OpenOption... options) throws IOException
+    {
+        if (options.length == 0)
+            return zfs.newOutputStream(getResolvedPath(),
+                                       CREATE, TRUNCATE_EXISTING, WRITE);
+        return zfs.newOutputStream(getResolvedPath(), options);
+    }
+
+    void move(ZipPath target, CopyOption... options)
+        throws IOException
+    {
+        if (Files.isSameFile(this.zfs.getZipFile(), target.zfs.getZipFile()))
+        {
+            zfs.copyFile(true,
+                         getResolvedPath(), target.getResolvedPath(),
+                         options);
+        } else {
+            copyToTarget(target, options);
+            delete();
+        }
+    }
+
+    void copy(ZipPath target, CopyOption... options)
+        throws IOException
+    {
+        if (Files.isSameFile(this.zfs.getZipFile(), target.zfs.getZipFile()))
+            zfs.copyFile(false,
+                         getResolvedPath(), target.getResolvedPath(),
+                         options);
+        else
+            copyToTarget(target, options);
+    }
+
+    private void copyToTarget(ZipPath target, CopyOption... options)
+        throws IOException
+    {
+        boolean replaceExisting = false;
+        boolean copyAttrs = false;
+        for (CopyOption opt : options) {
+            if (opt == REPLACE_EXISTING)
+                replaceExisting = true;
+            else if (opt == COPY_ATTRIBUTES)
+                copyAttrs = true;
+        }
+        // attributes of source file
+        ZipFileAttributes zfas = getAttributes();
+        // check if target exists
+        boolean exists;
+        if (replaceExisting) {
+            try {
+                target.deleteIfExists();
+                exists = false;
+            } catch (DirectoryNotEmptyException x) {
+                exists = true;
+            }
+        } else {
+            exists = target.exists();
+        }
+        if (exists)
+            throw new FileAlreadyExistsException(target.toString());
+
+        if (zfas.isDirectory()) {
+            // create directory or file
+            target.createDirectory();
+        } else {
+            InputStream is = zfs.newInputStream(getResolvedPath());
+            try {
+                OutputStream os = target.newOutputStream();
+                try {
+                    byte[] buf = new byte[8192];
+                    int n = 0;
+                    while ((n = is.read(buf)) != -1) {
+                        os.write(buf, 0, n);
+                    }
+                } finally {
+                    os.close();
+                }
+            } finally {
+                is.close();
+            }
+        }
+        if (copyAttrs) {
+            BasicFileAttributeView view =
+                ZipFileAttributeView.get(target, BasicFileAttributeView.class);
+            try {
+                view.setTimes(zfas.lastModifiedTime(),
+                              zfas.lastAccessTime(),
+                              zfas.creationTime());
+            } catch (IOException x) {
+                // rollback?
+                try {
+                    target.delete();
+                } catch (IOException ignore) { }
+                throw x;
+            }
+        }
+    }
+
+    private static int decode(char c) {
+        if ((c >= '0') && (c <= '9'))
+            return c - '0';
+        if ((c >= 'a') && (c <= 'f'))
+            return c - 'a' + 10;
+        if ((c >= 'A') && (c <= 'F'))
+            return c - 'A' + 10;
+        assert false;
+        return -1;
+    }
+
+    // to avoid double escape
+    static String decodeUri(String s) {
+        if (s == null)
+            return s;
+        int n = s.length();
+        if (n == 0)
+            return s;
+        if (s.indexOf('%') < 0)
+            return s;
+
+        StringBuilder sb = new StringBuilder(n);
+        byte[] bb = new byte[n];
+        boolean betweenBrackets = false;
+
+        for (int i = 0; i < n;) {
+            char c = s.charAt(i);
+            if (c == '[') {
+                betweenBrackets = true;
+            } else if (betweenBrackets && c == ']') {
+                betweenBrackets = false;
+            }
+            if (c != '%' || betweenBrackets ) {
+                sb.append(c);
+                i++;
+                continue;
+            }
+            int nb = 0;
+            while (c == '%') {
+                assert (n - i >= 2);
+                bb[nb++] = (byte)(((decode(s.charAt(++i)) & 0xf) << 4) |
+                                  (decode(s.charAt(++i)) & 0xf));
+                if (++i >= n) {
+                    break;
+                }
+                c = s.charAt(i);
+            }
+            sb.append(new String(bb, 0, nb, UTF_8));
+        }
+        return sb.toString();
+    }
+}