gcc/libjava/java/io/InputStreamReader.java

152 lines
3.1 KiB
Java

/* 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;
import gnu.gcj.convert.*;
/**
* @author Per Bothner <bothner@cygnus.com>
* @date April 22, 1998.
*/
/* Written using "Java Class Libraries", 2nd edition, plus online
* API docs for JDK 1.2 beta from http://www.javasoft.com.
* Status: Believed complete and correct, but only supports 8859_1.
*/
public class InputStreamReader extends Reader
{
BufferedInputStream in;
// Buffer of chars read from in and converted but not consumed.
char[] work;
// Next available character (in work buffer) to read.
int wpos;
// Last available character (in work buffer) to read.
int wcount;
BytesToUnicode converter;
public InputStreamReader(InputStream in)
{
this(in, BytesToUnicode.getDefaultDecoder());
}
public InputStreamReader(InputStream in, String enc)
throws UnsupportedEncodingException
{
this(in, BytesToUnicode.getDecoder(enc));
}
private InputStreamReader(InputStream in, BytesToUnicode decoder)
{
super((this.in = (in instanceof BufferedInputStream
? (BufferedInputStream) in
: new BufferedInputStream(in, 250))));
converter = decoder;
converter.setInput(this.in.buf, 0, 0);
}
public void close() throws IOException
{
synchronized (lock)
{
if (in != null)
in.close();
in = null;
work = null;
wpos = wcount = 0;
}
}
public String getEncoding() { return converter.getName(); }
public boolean ready() throws IOException
{
synchronized (lock)
{
if (wpos < wcount)
return true;
if (work == null)
{
work = new char[100];
wpos = 0;
wcount = 0;
}
for (;;)
{
if (in.available() <= 0)
return false;
in.mark(1);
int b = in.read();
if (b < 0)
return true;
in.reset();
converter.setInput(in.buf, in.pos, in.count);
wpos = 0;
wcount = converter.read(work, 0, work.length);
in.skip(converter.inpos - in.pos);
if (wcount > 0)
return true;
}
}
}
public int read(char buf[], int offset, int length) throws IOException
{
synchronized (lock)
{
int wavail = wcount - wpos;
if (wavail > 0)
{
if (length > wavail)
length = wavail;
System.arraycopy(work, wpos, buf, offset, length);
wpos += length;
return length;
}
else
{
for (;;)
{
in.mark(1);
int b = in.read();
if (b < 0)
return -1;
in.reset();
converter.setInput(in.buf, in.pos, in.count);
int count = converter.read (buf, offset, length);
in.skip(converter.inpos - in.pos);
if (count > 0)
return count;
}
}
}
}
public int read() throws IOException
{
synchronized (lock)
{
int wavail = wcount - wpos;
if (wavail > 0)
return work[wpos++];
if (work == null)
{
work = new char[100];
wpos = 0;
wcount = 0;
}
int count = read(work, wpos, work.length-wpos);
if (count <= 0)
return -1;
wcount = wpos + count;
return work[wpos++];
}
}
}