gcc/libjava/java/io/FileDescriptor.java

88 lines
2.5 KiB
Java

// FileDescriptor.java - Open file or device
/* Copyright (C) 1998, 1999 Cygnus Solutions
This file is part of libgcj.
This software is copyrighted work licensed under the terms of the
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
details. */
package java.io;
/**
* @author Tom Tromey <tromey@cygnus.com>
* @date September 24, 1998
*/
/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
* "The Java Language Specification", ISBN 0-201-63451-1
* Status: Complete to 1.1
*/
// For now we assume a POSIXy file system. This can be changed later
// if need be.
public final class FileDescriptor
{
public static final FileDescriptor in = new FileDescriptor (0);
public static final FileDescriptor out = new FileDescriptor (1);
public static final FileDescriptor err = new FileDescriptor (2);
public native void sync () throws SyncFailedException;
public native boolean valid ();
// These are mode values for open().
static final int READ = 1;
static final int WRITE = 2;
static final int APPEND = 4;
// These are WHENCE values for seek.
static final int SET = 0;
static final int CUR = 1;
// Open a file. MODE is a combination of the above mode flags.
FileDescriptor (String path, int mode) throws IOException
{
fd = open (path, mode);
}
public FileDescriptor ()
{
fd = -1;
}
native int open (String path, int mode) throws IOException;
native void write (int b) throws IOException;
native void write (byte[] b, int offset, int len)
throws IOException, NullPointerException, IndexOutOfBoundsException;
native void close () throws IOException;
native int seek (long pos, int whence) throws IOException;
native long length () throws IOException;
native long getFilePointer () throws IOException;
native int read () throws IOException;
native int read (byte[] bytes, int offset, int len) throws IOException;
native int available () throws IOException;
// When collected, close.
protected void finalize () throws IOException
{
if (valid ())
close ();
}
// Attach to an already-opened file. This is not private because we
// need access to it from other packages, for instance java.net.
// Ordinarily that wouldn't work, either, but in our case we know
// the access comes from C++, where "package private" is translated
// into "public". Eww.
FileDescriptor (int desc)
{
fd = desc;
}
// System's notion of file descriptor.
private int fd;
}