1398 lines
44 KiB
Java
1398 lines
44 KiB
Java
/* File.java -- Class representing a file on disk
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Copyright (C) 1998, 1999, 2000, 2001, 2003, 2004, 2005
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Free Software Foundation, Inc.
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This file is part of GNU Classpath.
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GNU Classpath is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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GNU Classpath is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GNU Classpath; see the file COPYING. If not, write to the
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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301 USA.
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Linking this library statically or dynamically with other modules is
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making a combined work based on this library. Thus, the terms and
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conditions of the GNU General Public License cover the whole
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combination.
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As a special exception, the copyright holders of this library give you
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permission to link this library with independent modules to produce an
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executable, regardless of the license terms of these independent
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modules, and to copy and distribute the resulting executable under
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terms of your choice, provided that you also meet, for each linked
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independent module, the terms and conditions of the license of that
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module. An independent module is a module which is not derived from
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or based on this library. If you modify this library, you may extend
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this exception to your version of the library, but you are not
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obligated to do so. If you do not wish to do so, delete this
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exception statement from your version. */
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package java.io;
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import java.net.MalformedURLException;
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import java.net.URI;
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import java.net.URISyntaxException;
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import java.net.URL;
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import gnu.classpath.Configuration;
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import gnu.gcj.runtime.FileDeleter;
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/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
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* "The Java Language Specification", ISBN 0-201-63451-1
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* Status: Complete to version 1.3.
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*/
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/**
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* This class represents a file or directory on a local disk. It provides
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* facilities for dealing with a variety of systems that use various
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* types of path separators ("/" versus "\", for example). It also
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* contains method useful for creating and deleting files and directories.
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*
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* @author Aaron M. Renn (arenn@urbanophile.com)
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* @author Tom Tromey (tromey@cygnus.com)
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*/
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public class File implements Serializable, Comparable
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{
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private static final long serialVersionUID = 301077366599181567L;
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// QUERY arguments to access function.
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private final static int READ = 0;
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private final static int WRITE = 1;
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private final static int EXISTS = 2;
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// QUERY arguments to stat function.
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private final static int DIRECTORY = 0;
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private final static int ISFILE = 1;
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private final static int ISHIDDEN = 2;
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// QUERY arguments to attr function.
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private final static int MODIFIED = 0;
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private final static int LENGTH = 1;
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private final native long attr (int query);
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// On OSF1 V5.0, `stat' is a macro. It is easiest to use the name
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// `_stat' instead. We do the same thing for `_access' just in
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// case.
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private final native boolean _access (int query);
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private final native boolean _stat (int query);
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/**
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* This is the path separator string for the current host. This field
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* contains the value of the <code>file.separator</code> system property.
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* An example separator string would be "/" on the GNU system.
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*/
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public static final String separator = System.getProperty("file.separator");
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private static final String dupSeparator = separator + separator;
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/**
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* This is the first character of the file separator string. On many
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* hosts (for example, on the GNU system), this represents the entire
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* separator string. The complete separator string is obtained from the
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* <code>file.separator</code>system property.
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*/
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public static final char separatorChar = separator.charAt(0);
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/**
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* This is the string that is used to separate the host name from the
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* path name in paths than include the host name. It is the value of
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* the <code>path.separator</code> system property.
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*/
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public static final String pathSeparator
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= System.getProperty("path.separator");
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/**
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* This is the first character of the string used to separate the host name
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* from the path name in paths that include a host. The separator string
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* is taken from the <code>path.separator</code> system property.
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*/
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public static final char pathSeparatorChar = pathSeparator.charAt(0);
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static final String tmpdir = System.getProperty("java.io.tmpdir");
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static int maxPathLen;
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static boolean caseSensitive;
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static
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{
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if (Configuration.INIT_LOAD_LIBRARY)
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{
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System.loadLibrary("javaio");
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}
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init_native();
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}
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// Native function called at class initialization. This should should
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// set the maxPathLen and caseSensitive variables.
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private static native void init_native();
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/**
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* This is the path to the file set when the object is created. It
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* may be an absolute or relative path name.
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*/
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private String path;
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// We keep a counter for use by createTempFile. We choose the first
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// value randomly to try to avoid clashes with other VMs.
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private static long counter = Double.doubleToLongBits (Math.random());
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/**
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* This method tests whether or not the current thread is allowed to
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* to read the file pointed to by this object. This will be true if and
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* and only if 1) the file exists and 2) the <code>SecurityManager</code>
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* (if any) allows access to the file via it's <code>checkRead</code>
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* method 3) the file is readable.
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*
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* @return <code>true</code> if reading is allowed,
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* <code>false</code> otherwise
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*
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* @exception SecurityException If the <code>SecurityManager</code>
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* does not allow access to the file
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*/
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public boolean canRead()
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{
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checkRead();
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return _access (READ);
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}
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/**
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* This method test whether or not the current thread is allowed to
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* write to this object. This will be true if and only if 1) The
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* <code>SecurityManager</code> (if any) allows write access to the
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* file and 2) The file exists and 3) The file is writable. To determine
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* whether or not a non-existent file can be created, check the parent
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* directory for write access.
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*
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* @return <code>true</code> if writing is allowed, <code>false</code>
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* otherwise
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*
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* @exception SecurityException If the <code>SecurityManager</code>
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* does not allow access to the file
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*/
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public boolean canWrite()
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{
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checkWrite();
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return _access (WRITE);
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}
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private native boolean performCreate() throws IOException;
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/**
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* This method creates a new file of zero length with the same name as
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* the path of this <code>File</code> object if an only if that file
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* does not already exist.
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* <p>
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* A <code>SecurityManager.checkWrite</code> check is done prior
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* to performing this action.
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*
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* @return <code>true</code> if the file was created, <code>false</code> if
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* the file alread existed.
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*
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* @exception IOException If an I/O error occurs
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* @exception SecurityException If the <code>SecurityManager</code> will
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* not allow this operation to be performed.
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*
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* @since 1.2
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*/
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public boolean createNewFile() throws IOException
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{
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checkWrite();
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return performCreate();
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}
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/*
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* This native method handles the actual deleting of the file
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*/
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private native boolean performDelete();
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/**
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* This method deletes the file represented by this object. If this file
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* is a directory, it must be empty in order for the delete to succeed.
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*
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* @return <code>true</code> if the file was deleted, <code>false</code>
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* otherwise
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*
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* @exception SecurityException If deleting of the file is not allowed
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*/
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public synchronized boolean delete()
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{
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SecurityManager s = System.getSecurityManager();
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if (s != null)
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s.checkDelete(path);
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return performDelete();
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}
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/**
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* This method tests two <code>File</code> objects for equality by
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* comparing the path of the specified <code>File</code> against the path
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* of this object. The two objects are equal if an only if 1) The
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* argument is not null 2) The argument is a <code>File</code> object and
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* 3) The path of the <code>File</code>argument is equal to the path
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* of this object.
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* <p>
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* The paths of the files are determined by calling the
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* <code>getPath()</code>
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* method on each object.
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*
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* @return <code>true</code> if the two objects are equal,
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* <code>false</code> otherwise.
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*/
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public boolean equals(Object obj)
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{
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if (! (obj instanceof File))
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return false;
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File other = (File) obj;
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if (caseSensitive)
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return path.equals(other.path);
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else
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return path.equalsIgnoreCase(other.path);
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}
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/**
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* This method tests whether or not the file represented by the object
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* actually exists on the filesystem.
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*
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* @return <code>true</code> if the file exists, <code>false</code>otherwise.
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*
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* @exception SecurityException If reading of the file is not permitted
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*/
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public boolean exists()
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{
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checkRead();
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return _access (EXISTS);
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}
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/**
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* This method initializes a new <code>File</code> object to represent
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* a file with the specified path.
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*
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* @param name The path name of the file
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*/
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public File(String name)
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{
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path = normalizePath (name);
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}
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// Remove duplicate and redundant separator characters.
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private String normalizePath(String p)
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{
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// On Windows, convert any '/' to '\'. This appears to be the same logic
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// that Sun's Win32 Java performs.
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if (separatorChar == '\\')
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{
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p = p.replace ('/', '\\');
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// We have to special case the "\c:" prefix.
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if (p.length() > 2 && p.charAt(0) == '\\' &&
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((p.charAt(1) >= 'a' && p.charAt(1) <= 'z') ||
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(p.charAt(1) >= 'A' && p.charAt(1) <= 'Z')) &&
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p.charAt(2) == ':')
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p = p.substring(1);
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}
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int dupIndex = p.indexOf(dupSeparator);
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int plen = p.length();
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// Special case: permit Windows UNC path prefix.
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if (dupSeparator.equals("\\\\") && dupIndex == 0)
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dupIndex = p.indexOf(dupSeparator, 1);
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if (dupIndex == -1)
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{
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// Ignore trailing separator (though on Windows "a:\", for
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// example, is a valid and minimal path).
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if (plen > 1 && p.charAt (plen - 1) == separatorChar)
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{
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if (! (separatorChar == '\\' && plen == 3 && p.charAt (1) == ':'))
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return p.substring (0, plen - 1);
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}
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else
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return p;
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}
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StringBuffer newpath = new StringBuffer(plen);
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int last = 0;
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while (dupIndex != -1)
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{
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newpath.append(p.substring(last, dupIndex));
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// Ignore the duplicate path characters.
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while (p.charAt(dupIndex) == separatorChar)
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{
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dupIndex++;
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if (dupIndex == plen)
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return newpath.toString();
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}
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newpath.append(separatorChar);
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last = dupIndex;
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dupIndex = p.indexOf(dupSeparator, last);
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}
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// Again, ignore possible trailing separator (except special cases
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// like "a:\" on Windows).
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int end;
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if (plen > 1 && p.charAt (plen - 1) == separatorChar)
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{
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if (separatorChar == '\\' && plen == 3 && p.charAt (1) == ':')
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end = plen;
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else
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end = plen - 1;
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}
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else
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end = plen;
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newpath.append(p.substring(last, end));
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return newpath.toString();
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}
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/**
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* This method initializes a new <code>File</code> object to represent
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* a file in the specified named directory. The path name to the file
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* will be the directory name plus the separator string plus the file
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* name. If the directory path name ends in the separator string, another
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* separator string will still be appended.
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*
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* @param dirPath The path to the directory the file resides in
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* @param name The name of the file
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*/
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public File(String dirPath, String name)
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{
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if (name == null)
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throw new NullPointerException();
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if (dirPath != null)
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{
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if (dirPath.length() > 0)
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{
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// Try to be smart about the number of separator characters.
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if (dirPath.charAt(dirPath.length() - 1) == separatorChar
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|| name.length() == 0)
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path = normalizePath(dirPath + name);
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else
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path = normalizePath(dirPath + separatorChar + name);
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}
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else
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{
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// If dirPath is empty, use a system dependant
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// default prefix.
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// Note that the leading separators in name have
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// to be chopped off, to prevent them forming
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// a UNC prefix on Windows.
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if (separatorChar == '\\' /* TODO use ON_WINDOWS */)
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{
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int skip = 0;
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while(name.length() > skip
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&& (name.charAt(skip) == separatorChar
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|| name.charAt(skip) == '/'))
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{
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skip++;
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}
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name = name.substring(skip);
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}
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path = normalizePath(separatorChar + name);
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}
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}
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else
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path = normalizePath(name);
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}
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/**
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* This method initializes a new <code>File</code> object to represent
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* a file in the specified directory. If the <code>directory</code>
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* argument is <code>null</code>, the file is assumed to be in the
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* current directory as specified by the <code>user.dir</code> system
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* property
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*
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* @param directory The directory this file resides in
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* @param name The name of the file
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*/
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public File(File directory, String name)
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{
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this (directory == null ? null : directory.path, name);
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}
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/**
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* This method initializes a new <code>File</code> object to represent
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* a file corresponding to the specified <code>file:</code> protocol URI.
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*
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* @param uri The uri.
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*/
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public File(URI uri)
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{
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if (uri == null)
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throw new NullPointerException("uri is null");
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if (!uri.getScheme().equals("file"))
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throw new IllegalArgumentException("invalid uri protocol");
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path = normalizePath(uri.getPath());
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}
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/**
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* This method returns the path of this file as an absolute path name.
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* If the path name is already absolute, then it is returned. Otherwise
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* the value returned is the current directory plus the separatory
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* string plus the path of the file. The current directory is determined
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* from the <code>user.dir</code> system property.
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*
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* @return The absolute path of this file
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*/
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public String getAbsolutePath()
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{
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if (isAbsolute())
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return path;
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else if (separatorChar == '\\'
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&& path.length() > 0 && path.charAt (0) == '\\')
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{
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// On Windows, even if the path starts with a '\\' it is not
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// really absolute until we prefix the drive specifier from
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// the current working directory to it.
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return System.getProperty ("user.dir").substring (0, 2) + path;
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}
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else if (separatorChar == '\\'
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&& path.length() > 1 && path.charAt (1) == ':'
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&& ((path.charAt (0) >= 'a' && path.charAt (0) <= 'z')
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|| (path.charAt (0) >= 'A' && path.charAt (0) <= 'Z')))
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{
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// On Windows, a process has a current working directory for
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// each drive and a path like "G:foo\bar" would mean the
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// absolute path "G:\wombat\foo\bar" if "\wombat" is the
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// working directory on the G drive.
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String drvDir = null;
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try
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{
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drvDir = new File (path.substring (0, 2)).getCanonicalPath();
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}
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catch (IOException e)
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{
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drvDir = path.substring (0, 2) + "\\";
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}
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|
|
|
// Note: this would return "C:\\." for the path "C:.", if "\"
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|
// is the working folder on the C drive, but this is
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|
// consistent with what Sun's JRE 1.4.1.01 actually returns!
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|
if (path.length() > 2)
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|
return drvDir + '\\' + path.substring (2, path.length());
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|
else
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|
return drvDir;
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|
}
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|
else
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return System.getProperty ("user.dir") + separatorChar + path;
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}
|
|
|
|
/**
|
|
* This method returns a <code>File</code> object representing the
|
|
* absolute path of this object.
|
|
*
|
|
* @return A <code>File</code> with the absolute path of the object.
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*
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* @since 1.2
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*/
|
|
public File getAbsoluteFile()
|
|
{
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return new File(getAbsolutePath());
|
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}
|
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|
|
/**
|
|
* This method returns a canonical representation of the pathname of
|
|
* this file. The actual form of the canonical representation is
|
|
* different. On the GNU system, the canonical form differs from the
|
|
* absolute form in that all relative file references to "." and ".."
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|
* are resolved and removed.
|
|
* <p>
|
|
* Note that this method, unlike the other methods which return path
|
|
* names, can throw an IOException. This is because native method
|
|
* might be required in order to resolve the canonical path
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|
*
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|
* @exception IOException If an error occurs
|
|
*/
|
|
public native String getCanonicalPath() throws IOException;
|
|
|
|
/**
|
|
* This method returns a <code>File</code> object representing the
|
|
* canonical path of this object.
|
|
*
|
|
* @return A <code>File</code> instance representing the canonical path of
|
|
* this object.
|
|
*
|
|
* @exception IOException If an error occurs.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public File getCanonicalFile() throws IOException
|
|
{
|
|
return new File(getCanonicalPath());
|
|
}
|
|
|
|
/**
|
|
* This method returns the name of the file. This is everything in the
|
|
* complete path of the file after the last instance of the separator
|
|
* string.
|
|
*
|
|
* @return The file name
|
|
*/
|
|
public String getName()
|
|
{
|
|
int nameSeqIndex = 0;
|
|
|
|
if (separatorChar == '\\' && path.length() > 1)
|
|
{
|
|
// On Windows, ignore the drive specifier or the leading '\\'
|
|
// of a UNC network path, if any (a.k.a. the "prefix").
|
|
if ((path.charAt (0) == '\\' && path.charAt (1) == '\\')
|
|
|| (((path.charAt (0) >= 'a' && path.charAt (0) <= 'z')
|
|
|| (path.charAt (0) >= 'A' && path.charAt (0) <= 'Z'))
|
|
&& path.charAt (1) == ':'))
|
|
{
|
|
if (path.length() > 2)
|
|
nameSeqIndex = 2;
|
|
else
|
|
return "";
|
|
}
|
|
}
|
|
|
|
String nameSeq
|
|
= (nameSeqIndex > 0 ? path.substring (nameSeqIndex) : path);
|
|
|
|
int last = nameSeq.lastIndexOf (separatorChar);
|
|
|
|
return nameSeq.substring (last + 1);
|
|
}
|
|
|
|
/**
|
|
* This method returns a <code>String</code> the represents this file's
|
|
* parent. <code>null</code> is returned if the file has no parent. The
|
|
* parent is determined via a simple operation which removes the
|
|
*
|
|
* @return The parent directory of this file
|
|
*/
|
|
public String getParent()
|
|
{
|
|
String prefix = null;
|
|
int nameSeqIndex = 0;
|
|
|
|
// The "prefix", if present, is the leading "/" on UNIX and
|
|
// either the drive specifier (e.g. "C:") or the leading "\\"
|
|
// of a UNC network path on Windows.
|
|
if (separatorChar == '/' && path.charAt (0) == '/')
|
|
{
|
|
prefix = "/";
|
|
nameSeqIndex = 1;
|
|
}
|
|
else if (separatorChar == '\\' && path.length() > 1)
|
|
{
|
|
if ((path.charAt (0) == '\\' && path.charAt (1) == '\\')
|
|
|| (((path.charAt (0) >= 'a' && path.charAt (0) <= 'z')
|
|
|| (path.charAt (0) >= 'A' && path.charAt (0) <= 'Z'))
|
|
&& path.charAt (1) == ':'))
|
|
{
|
|
prefix = path.substring (0, 2);
|
|
nameSeqIndex = 2;
|
|
}
|
|
}
|
|
|
|
// According to the JDK docs, the returned parent path is the
|
|
// portion of the name sequence before the last separator
|
|
// character, if found, prefixed by the prefix, otherwise null.
|
|
if (nameSeqIndex < path.length())
|
|
{
|
|
String nameSeq = path.substring (nameSeqIndex, path.length());
|
|
int last = nameSeq.lastIndexOf (separatorChar);
|
|
if (last == -1)
|
|
return prefix;
|
|
else if (last == (nameSeq.length() - 1))
|
|
// Note: The path would not have a trailing separator
|
|
// except for cases like "C:\" on Windows (see
|
|
// normalizePath( )), where Sun's JRE 1.4 returns null.
|
|
return null;
|
|
else if (last == 0)
|
|
last++;
|
|
|
|
if (prefix != null)
|
|
return prefix + nameSeq.substring (0, last);
|
|
else
|
|
return nameSeq.substring (0, last);
|
|
}
|
|
else
|
|
// Sun's JRE 1.4 returns null if the prefix is the only
|
|
// component of the path - so "/" gives null on UNIX and
|
|
// "C:", "\\", etc. return null on Windows.
|
|
return null;
|
|
}
|
|
|
|
/**
|
|
* This method returns a <code>File</code> object representing the parent
|
|
* file of this one.
|
|
*
|
|
* @return a <code>File</code> for the parent of this object.
|
|
* <code>null</code>
|
|
* will be returned if this object does not have a parent.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public File getParentFile()
|
|
{
|
|
String parent = getParent();
|
|
return parent != null ? new File(parent) : null;
|
|
}
|
|
|
|
/**
|
|
* Returns the path name that represents this file. May be a relative
|
|
* or an absolute path name
|
|
*
|
|
* @return The pathname of this file
|
|
*/
|
|
public String getPath()
|
|
{
|
|
return path;
|
|
}
|
|
|
|
/**
|
|
* This method returns a hash code representing this file. It is the
|
|
* hash code of the path of this file (as returned by <code>getPath()</code>)
|
|
* exclusived or-ed with the value 1234321.
|
|
*
|
|
* @return The hash code for this object
|
|
*/
|
|
public int hashCode()
|
|
{
|
|
if (caseSensitive)
|
|
return path.hashCode() ^ 1234321;
|
|
else
|
|
return path.toLowerCase().hashCode() ^ 1234321;
|
|
}
|
|
|
|
/**
|
|
* This method returns true if this object represents an absolute file
|
|
* path and false if it does not. The definition of an absolute path varies
|
|
* by system. As an example, on GNU systems, a path is absolute if it starts
|
|
* with a "/".
|
|
*
|
|
* @return <code>true</code> if this object represents an absolute
|
|
* file name, <code>false</code> otherwise.
|
|
*/
|
|
public native boolean isAbsolute();
|
|
|
|
/**
|
|
* This method tests whether or not the file represented by this object
|
|
* is a directory. In order for this method to return <code>true</code>,
|
|
* the file represented by this object must exist and be a directory.
|
|
*
|
|
* @return <code>true</code> if this file is a directory, <code>false</code>
|
|
* otherwise
|
|
*
|
|
* @exception SecurityException If reading of the file is not permitted
|
|
*/
|
|
public boolean isDirectory()
|
|
{
|
|
checkRead();
|
|
return _stat (DIRECTORY);
|
|
}
|
|
|
|
/**
|
|
* This method tests whether or not the file represented by this object
|
|
* is a "plain" file. A file is a plain file if and only if it 1) Exists,
|
|
* 2) Is not a directory or other type of special file.
|
|
*
|
|
* @return <code>true</code> if this is a plain file, <code>false</code>
|
|
* otherwise
|
|
*
|
|
* @exception SecurityException If reading of the file is not permitted
|
|
*/
|
|
public boolean isFile()
|
|
{
|
|
checkRead();
|
|
return _stat (ISFILE);
|
|
}
|
|
|
|
/**
|
|
* This method tests whether or not this file represents a "hidden" file.
|
|
* On GNU systems, a file is hidden if its name begins with a "."
|
|
* character. Files with these names are traditionally not shown with
|
|
* directory listing tools.
|
|
*
|
|
* @return <code>true</code> if the file is hidden, <code>false</code>
|
|
* otherwise.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public boolean isHidden()
|
|
{
|
|
checkRead();
|
|
return _stat (ISHIDDEN);
|
|
}
|
|
|
|
/**
|
|
* This method returns the last modification time of this file. The
|
|
* time value returned is an abstract value that should not be interpreted
|
|
* as a specified time value. It is only useful for comparing to other
|
|
* such time values returned on the same system. In that case, the larger
|
|
* value indicates a more recent modification time.
|
|
* <p>
|
|
* If the file does not exist, then a value of 0 is returned.
|
|
*
|
|
* @return The last modification time of the file
|
|
*
|
|
* @exception SecurityException If reading of the file is not permitted
|
|
*/
|
|
public long lastModified()
|
|
{
|
|
checkRead();
|
|
return attr (MODIFIED);
|
|
}
|
|
|
|
/**
|
|
* This method returns the length of the file represented by this object,
|
|
* or 0 if the specified file does not exist.
|
|
*
|
|
* @return The length of the file
|
|
*
|
|
* @exception SecurityException If reading of the file is not permitted
|
|
*/
|
|
public long length()
|
|
{
|
|
checkRead();
|
|
return attr (LENGTH);
|
|
}
|
|
|
|
/*
|
|
* This native function actually produces the list of file in this
|
|
* directory
|
|
*/
|
|
private final native Object[] performList (FilenameFilter filter,
|
|
FileFilter fileFilter,
|
|
Class result_type);
|
|
|
|
/**
|
|
* This method returns a array of <code>String</code>'s representing the
|
|
* list of files is then directory represented by this object. If this
|
|
* object represents a non-directory file or a non-existent file, then
|
|
* <code>null</code> is returned. The list of files will not contain
|
|
* any names such as "." or ".." which indicate the current or parent
|
|
* directory. Also, the names are not guaranteed to be sorted.
|
|
* <p>
|
|
* In this form of the <code>list()</code> method, a filter is specified
|
|
* that allows the caller to control which files are returned in the
|
|
* list. The <code>FilenameFilter</code> specified is called for each
|
|
* file returned to determine whether or not that file should be included
|
|
* in the list.
|
|
* <p>
|
|
* A <code>SecurityManager</code> check is made prior to reading the
|
|
* directory. If read access to the directory is denied, an exception
|
|
* will be thrown.
|
|
*
|
|
* @param filter An object which will identify files to exclude from
|
|
* the directory listing.
|
|
*
|
|
* @return An array of files in the directory, or <code>null</code>
|
|
* if this object does not represent a valid directory.
|
|
*
|
|
* @exception SecurityException If read access is not allowed to the
|
|
* directory by the <code>SecurityManager</code>
|
|
*/
|
|
public String[] list(FilenameFilter filter)
|
|
{
|
|
checkRead();
|
|
return (String[]) performList (filter, null, String.class);
|
|
}
|
|
|
|
/**
|
|
* This method returns a array of <code>String</code>'s representing the
|
|
* list of files is then directory represented by this object. If this
|
|
* object represents a non-directory file or a non-existent file, then
|
|
* <code>null</code> is returned. The list of files will not contain
|
|
* any names such as "." or ".." which indicate the current or parent
|
|
* directory. Also, the names are not guaranteed to be sorted.
|
|
* <p>
|
|
* A <code>SecurityManager</code> check is made prior to reading the
|
|
* directory. If read access to the directory is denied, an exception
|
|
* will be thrown.
|
|
*
|
|
* @return An array of files in the directory, or <code>null</code> if
|
|
* this object does not represent a valid directory.
|
|
*
|
|
* @exception SecurityException If read access is not allowed to the
|
|
* directory by the <code>SecurityManager</code>
|
|
*/
|
|
public String[] list()
|
|
{
|
|
checkRead();
|
|
return (String[]) performList (null, null, String.class);
|
|
}
|
|
|
|
/**
|
|
* This method returns an array of <code>File</code> objects representing
|
|
* all the files in the directory represented by this object. If this
|
|
* object does not represent a directory, <code>null</code> is returned.
|
|
* Each of the returned <code>File</code> object is constructed with this
|
|
* object as its parent.
|
|
* <p>
|
|
* A <code>SecurityManager</code> check is made prior to reading the
|
|
* directory. If read access to the directory is denied, an exception
|
|
* will be thrown.
|
|
*
|
|
* @return An array of <code>File</code> objects for this directory.
|
|
*
|
|
* @exception SecurityException If the <code>SecurityManager</code> denies
|
|
* access to this directory.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public File[] listFiles()
|
|
{
|
|
checkRead();
|
|
return (File[]) performList (null, null, File.class);
|
|
}
|
|
|
|
/**
|
|
* This method returns an array of <code>File</code> objects representing
|
|
* all the files in the directory represented by this object. If this
|
|
* object does not represent a directory, <code>null</code> is returned.
|
|
* Each of the returned <code>File</code> object is constructed with this
|
|
* object as its parent.
|
|
* <p>
|
|
* In this form of the <code>listFiles()</code> method, a filter is specified
|
|
* that allows the caller to control which files are returned in the
|
|
* list. The <code>FilenameFilter</code> specified is called for each
|
|
* file returned to determine whether or not that file should be included
|
|
* in the list.
|
|
* <p>
|
|
* A <code>SecurityManager</code> check is made prior to reading the
|
|
* directory. If read access to the directory is denied, an exception
|
|
* will be thrown.
|
|
*
|
|
* @return An array of <code>File</code> objects for this directory.
|
|
*
|
|
* @exception SecurityException If the <code>SecurityManager</code> denies
|
|
* access to this directory.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public File[] listFiles(FilenameFilter filter)
|
|
{
|
|
checkRead();
|
|
return (File[]) performList (filter, null, File.class);
|
|
}
|
|
|
|
/**
|
|
* This method returns an array of <code>File</code> objects representing
|
|
* all the files in the directory represented by this object. If this
|
|
* object does not represent a directory, <code>null</code> is returned.
|
|
* Each of the returned <code>File</code> object is constructed with this
|
|
* object as its parent.
|
|
* <p>
|
|
* In this form of the <code>listFiles()</code> method, a filter is specified
|
|
* that allows the caller to control which files are returned in the
|
|
* list. The <code>FileFilter</code> specified is called for each
|
|
* file returned to determine whether or not that file should be included
|
|
* in the list.
|
|
* <p>
|
|
* A <code>SecurityManager</code> check is made prior to reading the
|
|
* directory. If read access to the directory is denied, an exception
|
|
* will be thrown.
|
|
*
|
|
* @return An array of <code>File</code> objects for this directory.
|
|
*
|
|
* @exception SecurityException If the <code>SecurityManager</code> denies
|
|
* access to this directory.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public File[] listFiles(FileFilter filter)
|
|
{
|
|
checkRead();
|
|
return (File[]) performList (null, filter, File.class);
|
|
}
|
|
|
|
/**
|
|
* This method returns a <code>String</code> that is the path name of the
|
|
* file as returned by <code>getPath</code>.
|
|
*
|
|
* @return A <code>String</code> representation of this file
|
|
*/
|
|
public String toString()
|
|
{
|
|
return path;
|
|
}
|
|
|
|
/**
|
|
* @return A <code>URI</code> for this object.
|
|
*/
|
|
public URI toURI()
|
|
{
|
|
String abspath = getAbsolutePath();
|
|
|
|
if (isDirectory())
|
|
abspath = abspath + separator;
|
|
|
|
try
|
|
{
|
|
return new URI("file", abspath.replace(separatorChar, '/'), null);
|
|
}
|
|
catch (URISyntaxException use)
|
|
{
|
|
// Can't happen.
|
|
throw new RuntimeException(use);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* This method returns a <code>URL</code> with the <code>file:</code>
|
|
* protocol that represents this file. The exact form of this URL is
|
|
* system dependent.
|
|
*
|
|
* @return A <code>URL</code> for this object.
|
|
*
|
|
* @exception MalformedURLException If the URL cannot be created
|
|
* successfully.
|
|
*/
|
|
public URL toURL() throws MalformedURLException
|
|
{
|
|
// On Win32, Sun's JDK returns URLs of the form "file:/c:/foo/bar.txt",
|
|
// while on UNIX, it returns URLs of the form "file:/foo/bar.txt".
|
|
if (separatorChar == '\\')
|
|
return new URL ("file:/" + getAbsolutePath().replace ('\\', '/')
|
|
+ (isDirectory() ? "/" : ""));
|
|
else
|
|
return new URL ("file:" + getAbsolutePath()
|
|
+ (isDirectory() ? "/" : ""));
|
|
}
|
|
|
|
/*
|
|
* This native method actually creates the directory
|
|
*/
|
|
private final native boolean performMkdir();
|
|
|
|
/**
|
|
* This method creates a directory for the path represented by this object.
|
|
*
|
|
* @return <code>true</code> if the directory was created,
|
|
* <code>false</code> otherwise
|
|
*
|
|
* @exception SecurityException If write access is not allowed to this file
|
|
*/
|
|
public boolean mkdir()
|
|
{
|
|
checkWrite();
|
|
return performMkdir();
|
|
}
|
|
|
|
private static boolean mkdirs (File x)
|
|
{
|
|
if (x.isDirectory())
|
|
return true;
|
|
String p = x.getPath();
|
|
String parent = x.getParent();
|
|
if (parent != null)
|
|
{
|
|
x.path = parent;
|
|
if (! mkdirs (x))
|
|
return false;
|
|
x.path = p;
|
|
}
|
|
return x.mkdir();
|
|
}
|
|
|
|
/**
|
|
* This method creates a directory for the path represented by this file.
|
|
* It will also create any intervening parent directories if necessary.
|
|
*
|
|
* @return <code>true</code> if the directory was created,
|
|
* <code>false</code> otherwise
|
|
*
|
|
* @exception SecurityException If write access is not allowed to this file
|
|
*/
|
|
public boolean mkdirs()
|
|
{
|
|
checkWrite();
|
|
if (isDirectory())
|
|
return false;
|
|
return mkdirs (new File (path));
|
|
}
|
|
|
|
private static synchronized String nextValue()
|
|
{
|
|
return Long.toString(counter++, Character.MAX_RADIX);
|
|
}
|
|
|
|
/**
|
|
* This method creates a temporary file in the specified directory. If
|
|
* the directory name is null, then this method uses the system temporary
|
|
* directory. The files created are guaranteed not to currently exist and
|
|
* the same file name will never be used twice in the same virtual
|
|
* machine instance.
|
|
* The system temporary directory is determined by examinging the
|
|
* <code>java.io.tmpdir</code> system property.
|
|
* <p>
|
|
* The <code>prefix</code> parameter is a sequence of at least three
|
|
* characters that are used as the start of the generated filename. The
|
|
* <code>suffix</code> parameter is a sequence of characters that is used
|
|
* to terminate the file name. This parameter may be <code>null</code>
|
|
* and if it is, the suffix defaults to ".tmp".
|
|
* <p>
|
|
* If a <code>SecurityManager</code> exists, then its <code>checkWrite</code>
|
|
* method is used to verify that this operation is permitted.
|
|
*
|
|
* @param prefix The character prefix to use in generating the path name.
|
|
* @param suffix The character suffix to use in generating the path name.
|
|
* @param directory The directory to create the file in, or
|
|
* <code>null</code> for the default temporary directory
|
|
*
|
|
* @exception IllegalArgumentException If the patterns is not valid
|
|
* @exception SecurityException If there is no permission to perform
|
|
* this operation
|
|
* @exception IOException If an error occurs
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public static File createTempFile(String prefix, String suffix,
|
|
File directory)
|
|
throws IOException
|
|
{
|
|
// Grab the system temp directory if necessary
|
|
if (directory == null)
|
|
{
|
|
String dirname = tmpdir;
|
|
if (dirname == null)
|
|
throw new IOException("Cannot determine system temporary directory");
|
|
|
|
directory = new File(dirname);
|
|
if (!directory.exists())
|
|
throw new IOException("System temporary directory "
|
|
+ directory.getName() + " does not exist.");
|
|
if (!directory.isDirectory())
|
|
throw new IOException("System temporary directory "
|
|
+ directory.getName()
|
|
+ " is not really a directory.");
|
|
}
|
|
|
|
// Check if prefix is at least 3 characters long
|
|
if (prefix.length() < 3)
|
|
throw new IllegalArgumentException("Prefix too short: " + prefix);
|
|
|
|
// Set default value of suffix
|
|
if (suffix == null)
|
|
suffix = ".tmp";
|
|
|
|
// Truncation rules.
|
|
// `6' is the number of characters we generate.
|
|
if (prefix.length() + 6 + suffix.length() > maxPathLen)
|
|
{
|
|
int suf_len = 0;
|
|
if (suffix.charAt(0) == '.')
|
|
suf_len = 4;
|
|
suffix = suffix.substring(0, suf_len);
|
|
if (prefix.length() + 6 + suf_len > maxPathLen)
|
|
prefix = prefix.substring(0, maxPathLen - 6 - suf_len);
|
|
}
|
|
|
|
File f;
|
|
|
|
// How many times should we try? We choose 100.
|
|
for (int i = 0; i < 100; ++i)
|
|
{
|
|
// This is ugly.
|
|
String t = "ZZZZZZ" + nextValue();
|
|
String l = prefix + t.substring(t.length() - 6) + suffix;
|
|
try
|
|
{
|
|
f = new File(directory, l);
|
|
if (f.createNewFile())
|
|
return f;
|
|
}
|
|
catch (IOException ignored)
|
|
{
|
|
}
|
|
}
|
|
|
|
throw new IOException ("cannot create temporary file");
|
|
}
|
|
|
|
/*
|
|
* This native method sets the permissions to make the file read only.
|
|
*/
|
|
private native boolean performSetReadOnly();
|
|
|
|
/**
|
|
* This method sets the file represented by this object to be read only.
|
|
* A read only file or directory cannot be modified. Please note that
|
|
* GNU systems allow read only files to be deleted if the directory it
|
|
* is contained in is writable.
|
|
*
|
|
* @return <code>true</code> if the operation succeeded, <code>false</code>
|
|
* otherwise.
|
|
*
|
|
* @exception SecurityException If the <code>SecurityManager</code> does
|
|
* not allow this operation.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public boolean setReadOnly()
|
|
{
|
|
// Do a security check before trying to do anything else.
|
|
checkWrite();
|
|
return performSetReadOnly();
|
|
}
|
|
|
|
private static native File[] performListRoots();
|
|
|
|
/**
|
|
* This method returns an array of filesystem roots. Some operating systems
|
|
* have volume oriented filesystem. This method provides a mechanism for
|
|
* determining which volumes exist. GNU systems use a single hierarchical
|
|
* filesystem, so will have only one "/" filesystem root.
|
|
*
|
|
* @return An array of <code>File</code> objects for each filesystem root
|
|
* available.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public static File[] listRoots()
|
|
{
|
|
File[] roots = performListRoots();
|
|
|
|
SecurityManager s = System.getSecurityManager();
|
|
if (s != null)
|
|
{
|
|
// Only return roots to which the security manager permits read access.
|
|
int count = roots.length;
|
|
for (int i = 0; i < roots.length; i++)
|
|
{
|
|
try
|
|
{
|
|
s.checkRead (roots[i].path);
|
|
}
|
|
catch (SecurityException sx)
|
|
{
|
|
roots[i] = null;
|
|
count--;
|
|
}
|
|
}
|
|
if (count != roots.length)
|
|
{
|
|
File[] newRoots = new File[count];
|
|
int k = 0;
|
|
for (int i=0; i < roots.length; i++)
|
|
{
|
|
if (roots[i] != null)
|
|
newRoots[k++] = roots[i];
|
|
}
|
|
roots = newRoots;
|
|
}
|
|
}
|
|
return roots;
|
|
}
|
|
|
|
/**
|
|
* This method creates a temporary file in the system temporary directory.
|
|
* The files created are guaranteed not to currently exist and the same file
|
|
* name will never be used twice in the same virtual machine instance. The
|
|
* system temporary directory is determined by examinging the
|
|
* <code>java.io.tmpdir</code> system property.
|
|
* <p>
|
|
* The <code>prefix</code> parameter is a sequence of at least three
|
|
* characters that are used as the start of the generated filename. The
|
|
* <code>suffix</code> parameter is a sequence of characters that is used
|
|
* to terminate the file name. This parameter may be <code>null</code>
|
|
* and if it is, the suffix defaults to ".tmp".
|
|
* <p>
|
|
* If a <code>SecurityManager</code> exists, then its <code>checkWrite</code>
|
|
* method is used to verify that this operation is permitted.
|
|
* <p>
|
|
* This method is identical to calling
|
|
* <code>createTempFile(prefix, suffix, null)</code>.
|
|
*
|
|
* @param prefix The character prefix to use in generating the path name.
|
|
* @param suffix The character suffix to use in generating the path name.
|
|
*
|
|
* @exception IllegalArgumentException If the prefix or suffix are not valid.
|
|
* @exception SecurityException If there is no permission to perform
|
|
* this operation
|
|
* @exception IOException If an error occurs
|
|
*/
|
|
public static File createTempFile(String prefix, String suffix)
|
|
throws IOException
|
|
{
|
|
return createTempFile(prefix, suffix, null);
|
|
}
|
|
|
|
/**
|
|
* This method compares the specified <code>File</code> to this one
|
|
* to test for equality. It does this by comparing the canonical path names
|
|
* of the files.
|
|
* <p>
|
|
* The canonical paths of the files are determined by calling the
|
|
* <code>getCanonicalPath</code> method on each object.
|
|
* <p>
|
|
* This method returns a 0 if the specified <code>Object</code> is equal
|
|
* to this one, a negative value if it is less than this one
|
|
* a positive value if it is greater than this one.
|
|
*
|
|
* @return An integer as described above
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public int compareTo(File other)
|
|
{
|
|
if (caseSensitive)
|
|
return path.compareTo (other.path);
|
|
else
|
|
return path.compareToIgnoreCase (other.path);
|
|
}
|
|
|
|
/**
|
|
* This method compares the specified <code>Object</code> to this one
|
|
* to test for equality. It does this by comparing the canonical path names
|
|
* of the files. This method is identical to <code>compareTo(File)</code>
|
|
* except that if the <code>Object</code> passed to it is not a
|
|
* <code>File</code>, it throws a <code>ClassCastException</code>
|
|
* <p>
|
|
* The canonical paths of the files are determined by calling the
|
|
* <code>getCanonicalPath</code> method on each object.
|
|
* <p>
|
|
* This method returns a 0 if the specified <code>Object</code> is equal
|
|
* to this one, a negative value if it is less than this one
|
|
* a positive value if it is greater than this one.
|
|
*
|
|
* @return An integer as described above
|
|
*
|
|
* @exception ClassCastException If the passed <code>Object</code> is
|
|
* not a <code>File</code>
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public int compareTo(Object obj)
|
|
{
|
|
return compareTo((File) obj);
|
|
}
|
|
|
|
/*
|
|
* This native method actually performs the rename.
|
|
*/
|
|
private native boolean performRenameTo (File dest);
|
|
|
|
/**
|
|
* This method renames the file represented by this object to the path
|
|
* of the file represented by the argument <code>File</code>.
|
|
*
|
|
* @param dest The <code>File</code> object representing the target name
|
|
*
|
|
* @return <code>true</code> if the rename succeeds, <code>false</code>
|
|
* otherwise.
|
|
*
|
|
* @exception SecurityException If write access is not allowed to the
|
|
* file by the <code>SecurityMananger</code>.
|
|
*/
|
|
public synchronized boolean renameTo(File dest)
|
|
{
|
|
SecurityManager s = System.getSecurityManager();
|
|
String sname = getName();
|
|
String dname = dest.getName();
|
|
if (s != null)
|
|
{
|
|
s.checkWrite (sname);
|
|
s.checkWrite (dname);
|
|
}
|
|
return performRenameTo (dest);
|
|
}
|
|
|
|
/*
|
|
* This method does the actual setting of the modification time.
|
|
*/
|
|
private native boolean performSetLastModified(long time);
|
|
|
|
/**
|
|
* This method sets the modification time on the file to the specified
|
|
* value. This is specified as the number of seconds since midnight
|
|
* on January 1, 1970 GMT.
|
|
*
|
|
* @param time The desired modification time.
|
|
*
|
|
* @return <code>true</code> if the operation succeeded, <code>false</code>
|
|
* otherwise.
|
|
*
|
|
* @exception IllegalArgumentException If the specified time is negative.
|
|
* @exception SecurityException If the <code>SecurityManager</code> will
|
|
* not allow this operation.
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
public boolean setLastModified(long time)
|
|
{
|
|
if (time < 0)
|
|
throw new IllegalArgumentException("Negative modification time: " + time);
|
|
|
|
checkWrite();
|
|
return performSetLastModified(time);
|
|
}
|
|
|
|
private void checkWrite()
|
|
{
|
|
// Check the SecurityManager
|
|
SecurityManager s = System.getSecurityManager();
|
|
|
|
if (s != null)
|
|
s.checkWrite(path);
|
|
}
|
|
|
|
private void checkRead()
|
|
{
|
|
// Check the SecurityManager
|
|
SecurityManager s = System.getSecurityManager();
|
|
|
|
if (s != null)
|
|
s.checkRead(path);
|
|
}
|
|
|
|
/**
|
|
* Calling this method requests that the file represented by this object
|
|
* be deleted when the virtual machine exits. Note that this request cannot
|
|
* be cancelled. Also, it will only be carried out if the virtual machine
|
|
* exits normally.
|
|
*
|
|
* @exception SecurityException If deleting of the file is not allowed
|
|
*
|
|
* @since 1.2
|
|
*/
|
|
// FIXME: This should use the ShutdownHook API once we implement that.
|
|
public void deleteOnExit()
|
|
{
|
|
// Check the SecurityManager
|
|
SecurityManager sm = System.getSecurityManager();
|
|
if (sm != null)
|
|
sm.checkDelete (getName());
|
|
|
|
FileDeleter.add (this);
|
|
}
|
|
|
|
private void writeObject(ObjectOutputStream oos) throws IOException
|
|
{
|
|
oos.defaultWriteObject();
|
|
oos.writeChar(separatorChar);
|
|
}
|
|
|
|
private void readObject(ObjectInputStream ois)
|
|
throws ClassNotFoundException, IOException
|
|
{
|
|
ois.defaultReadObject();
|
|
|
|
// If the file was from an OS with a different dir separator,
|
|
// fixup the path to use the separator on this OS.
|
|
char oldSeparatorChar = ois.readChar();
|
|
|
|
if (oldSeparatorChar != separatorChar)
|
|
path = path.replace(oldSeparatorChar, separatorChar);
|
|
}
|
|
|
|
} // class File
|
|
|