mirror of git://gcc.gnu.org/git/gcc.git
114 lines
2.7 KiB
Java
114 lines
2.7 KiB
Java
/* Copyright (C) 1998, 1999 Free Software Foundation
|
|
|
|
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 Warren Levy <warrenl@cygnus.com>
|
|
* @date October 7, 1998.
|
|
*/
|
|
|
|
/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3
|
|
* "The Java Language Specification", ISBN 0-201-63451-1
|
|
* plus online API docs for JDK 1.2 beta from http://www.javasoft.com.
|
|
* Status: Believed complete and correct
|
|
*/
|
|
|
|
public class ByteArrayInputStream extends InputStream
|
|
{
|
|
/* An array of bytes provided by the creator of the stream. */
|
|
protected byte[] buf;
|
|
|
|
/* Position of the next byte in buf to be read. */
|
|
protected int pos;
|
|
|
|
/* The currently marked position in the stream. */
|
|
protected int mark;
|
|
|
|
/* The index in buf one greater than the last valid character. */
|
|
protected int count;
|
|
|
|
public ByteArrayInputStream(byte[] buffer)
|
|
{
|
|
this(buffer, 0, buffer.length);
|
|
}
|
|
|
|
public ByteArrayInputStream(byte[] buffer, int offset, int length)
|
|
{
|
|
buf = buffer;
|
|
|
|
count = offset + length;
|
|
if (count > buf.length)
|
|
count = buf.length;
|
|
|
|
pos = offset;
|
|
// TBD: What should we do if pos is neg. or > count? E.g. throw exc. or:
|
|
// if (pos < 0 || pos > count)
|
|
// pos = 0;
|
|
|
|
mark = pos;
|
|
}
|
|
|
|
public synchronized int available()
|
|
{
|
|
return count - pos;
|
|
}
|
|
|
|
public synchronized void mark(int readAheadLimit)
|
|
{
|
|
// readAheadLimit is ignored per Java Class Lib. book, p.220.
|
|
mark = pos;
|
|
}
|
|
|
|
public boolean markSupported()
|
|
{
|
|
return true;
|
|
}
|
|
|
|
public synchronized int read()
|
|
{
|
|
if (pos < 0)
|
|
throw new ArrayIndexOutOfBoundsException(pos);
|
|
|
|
if (pos < count)
|
|
return ((int) buf[pos++]) & 0xFF;
|
|
return -1;
|
|
}
|
|
|
|
public synchronized int read(byte[] b, int off, int len)
|
|
{
|
|
/* Don't need to check pos value, arraycopy will check it. */
|
|
if (off < 0 || len < 0 || off + len > b.length)
|
|
throw new ArrayIndexOutOfBoundsException();
|
|
|
|
if (pos >= count)
|
|
return -1;
|
|
|
|
int numBytes = Math.min(count - pos, len);
|
|
System.arraycopy(buf, pos, b, off, numBytes);
|
|
pos += numBytes;
|
|
return numBytes;
|
|
}
|
|
|
|
public synchronized void reset()
|
|
{
|
|
pos = mark;
|
|
}
|
|
|
|
public synchronized long skip(long n)
|
|
{
|
|
// Even though the var numBytes is a long, in reality it can never
|
|
// be larger than an int since the result of subtracting 2 positive
|
|
// ints will always fit in an int. Since we have to return a long
|
|
// anyway, numBytes might as well just be a long.
|
|
long numBytes = Math.min((long) (count - pos), n < 0 ? 0L : n);
|
|
pos += numBytes;
|
|
return numBytes;
|
|
}
|
|
}
|