Skip to content

R
riscv-gcc-1
Commit d3474943 by Tom Tromey Committed by Tom Tromey
Options

Fix for PR java.io/204: 

	* java/io/PipedInputStream.java, java/io/PipedReader.java,
	java/io/PipedOutputStream.java, java/io/PipedWriter.java: Imported
	from Classpath.

From-SVN: r33300
parent 21caf590
Showing with 1322 additions and 459 deletions
libjava/ChangeLog
2000-04-20 Tom Tromey <tromey@cygnus.com> 2000-04-20 Tom Tromey <tromey@cygnus.com>
Fix for PR java.io/204:
* java/io/PipedInputStream.java, java/io/PipedReader.java,
java/io/PipedOutputStream.java, java/io/PipedWriter.java: Imported
from Classpath.
Fix for PR libgcj/212: Fix for PR libgcj/212:
* gcj/javaprims.h (_Jv_word, _Jv_word2): Removed definitions. * gcj/javaprims.h (_Jv_word, _Jv_word2): Removed definitions.
* include/jvm.h (_Jv_word, _Jv_word2): Define. * include/jvm.h (_Jv_word, _Jv_word2): Define.
......
libjava/java/io/PipedInputStream.java
/* Copyright (C) 1998, 1999 Free Software Foundation /* PipedInputStream.java -- Input stream that reads from an output stream
Copyright (C) 1998, 1999 Free Software Foundation, Inc.
This file is part of libgcj. This file is part of GNU Classpath.
GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU Classpath 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 for more details.
You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.
As a special exception, if you link this library with other files to
produce an executable, this library does not by itself cause the
resulting executable to be covered by the GNU General Public License.
This exception does not however invalidate any other reasons why the
executable file might be covered by the GNU General Public License. */
This software is copyrighted work licensed under the terms of the
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
details. */
package java.io; package java.io;
/** /**
* @author Warren Levy <warrenl@cygnus.com> * This class is an input stream that reads its bytes from an output stream
* @date October 29, 1998. * to which it is connected.
* <p>
* Data is read and written to an internal buffer. It is highly recommended
* that the <code>PipedInputStream</code> and connected <code>PipedOutputStream</code>
* be part of different threads. If they are not, there is a possibility
* that the read and write operations could deadlock their thread.
*
* @version 0.0
*
* @author Aaron M. Renn (arenn@urbanophile.com)
*/
public class PipedInputStream extends InputStream
{
/*************************************************************************/
/*
* Class Variables
*/ */
/* 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. * The size of the internal buffer used for input/output. Note that this
* Status: Believed complete and correct. * can be overriden by setting the system property
* <code>gnu.java.io.PipedInputStream.pipe_size</code> to the desired size shown
* in bytes. This is not a standard part of the class library. Note that
* since this variable is <code>final</code>, it cannot be changed to refect
* the size specified in the property.
* <p>
* The value for this variable is 2048.
*/ */
protected static final int PIPE_SIZE = 2048;
public class PipedInputStream extends InputStream /**
* This is the real pipe size. It defaults to PIPE_SIZE, unless overridden
* by use of the system property <code>gnu.java.io.PipedInputStream.pipe_size</code>.
*/
private static int pipe_size;
/**
* This variable indicates whether or not the <code>read()</code> method will attempt
* return a short count if this will possibly keep the stream from blocking.
* The default for this is <code>false</code> because that is what what the JDK seems
* to imply in its javadocs. We set this to <code>false</code> if the system
* property <code>gnu.java.io.try_not_to_block</code> is set.
*/
private static boolean try_not_to_block = false;
static
{ {
/* The size of the pipe's circular input buffer. */ pipe_size = Integer.getInteger("gnu.java.io.PipedInputStream.pipe_size",
protected static final int PIPE_SIZE = 1024; PIPE_SIZE).intValue();
/* The circular buffer into which incoming data is placed. */ String block_prop = System.getProperty("gnu.java.io.try_not_to_block");
protected byte[] buffer; if (block_prop != null)
try_not_to_block = true;
}
/* The index in the buffer at which the next byte of data will be stored. */ /*************************************************************************/
protected int in = -1;
/* The index in the buffer at which the next byte of data will be read. */ /*
protected int out = 0; * Instance Variables
*/
/* The output stream this is connected to; used to check for errors. */ /**
private PipedOutputStream po = null; * This is the internal circular buffer used for storing bytes written
* to the pipe and from which bytes are read by this stream
*/
protected byte[] buffer = new byte[pipe_size];
/* Flag to indicate that the output stream was closed. */ /**
private boolean outClosed = false; * The index into buffer where the bytes written byte the connected
* <code>PipedOutputStream</code> will be written. If this variables is less
* than 0, then the buffer is empty. If this variable is equal to
* <code>out</code>, then the buffer is full
*/
protected int in = -1;
public PipedInputStream(PipedOutputStream src) throws IOException /**
{ * This index into the buffer where bytes will be read from.
buffer = new byte[PIPE_SIZE]; */
connect(src); protected int out = 0;
}
public PipedInputStream() /**
{ * This variable is <code>true</code> if this object has ever been connected
buffer = new byte[PIPE_SIZE]; * to a <code>PipedOutputStream</code>, and <code>false</code> otherwise. It is used
} * to detect an attempt to connect an already connected stream or to
* otherwise use the stream before it is connected.
*/
private boolean ever_connected = false;
public synchronized int available() throws IOException /**
{ * This variable is set to <code>true</code> if the <code>close()</code> method is
if (in < 0) * called. This value is checked prevents a caller from re-opening the
return 0; * stream.
*/
private boolean closed = false;
if (in > out) /**
return in - out; * This variable is the PipedOutputStream to which this stream is connected.
*/
PipedOutputStream src;
// Buffer has wrapped around. /**
return buffer.length - out + in; * Used by <code>read()</code> to call an overloaded method
} */
private byte[] read_buf = new byte[1];
public void close() throws IOException /*************************************************************************/
{
buffer = null;
po = null;
// Mark as empty for available method. /*
in = -1; * Constructors
} */
public void connect(PipedOutputStream src) throws IOException /**
{ * This constructor creates a new <code>PipedInputStream</code> that is not
if (buffer == null) * connected to a <code>PipedOutputStream</code>. It must be connected before
throw new IOException("pipe closed"); * bytes can be read from this stream.
*/
public
PipedInputStream()
{
return;
}
/*************************************************************************/
/**
* This constructor creates a new <code>PipedInputStream</code> and connects
* it to the passed in <code>PipedOutputStream</code>. The stream is then read
* for reading.
*
* @param src The <code>PipedOutputStream</code> to connect this stream to
*
* @exception IOException If an error occurs
*/
public
PipedInputStream(PipedOutputStream src) throws IOException
{
connect(src);
}
/*************************************************************************/
if (po != null) /*
if (po == src) * Instance Variables
*/
/**
* This method connects this stream to the passed in <code>PipedOutputStream</code>.
* This stream is then ready for reading. If this stream is already
* connected or has been previously closed, then an exception is thrown
*
* @param src The <code>PipedOutputStream</code> to connect this stream to
*
* @exception IOException If an error occurs
*/
public synchronized void
connect(PipedOutputStream src) throws IOException
{
if (src == this.src)
return; return;
if (ever_connected)
throw new IOException("Already connected");
if (closed)
throw new IOException("Stream is closed and cannot be reopened");
src.connect(this);
ever_connected = true;
}
/*************************************************************************/
/**
* This methods closes the stream so that no more data can be read
* from it.
*
* @exception IOException If an error occurs
*/
public synchronized void
close() throws IOException
{
closed = true;
notifyAll();
}
/*************************************************************************/
/**
* This method returns the number of bytes that can be read from this stream
* before blocking could occur. This is the number of bytes that are
* currently unread in the internal circular buffer. Note that once this
* many additional bytes are read, the stream may block on a subsequent
* read, but it not guaranteed to block.
*
* @return The number of bytes that can be read before blocking might occur
*
* @exception IOException If an error occurs
*/
public synchronized int
available() throws IOException
{
if (in == -1)
return(0);
else if (in > out)
return(in - out);
else else
throw new IOException("pipe already connected"); return(in + (pipe_size - out));
}
po = src; /*************************************************************************/
try
/**
* Reads the next byte from the stream. The byte read is returned as
* and int in the range of 0-255. If a byte cannot be read because of an
* end of stream condition, -1 is returned. If the stream is already
* closed, an IOException will be thrown.
* <code>
* This method will block if no bytes are available to be read.
*
* @return The byte read or -1 if end of stream.
*
* @exception IOException If an error occurs
*/
public synchronized int
read() throws IOException
{
// Method operates by calling the multibyte overloaded read method
// Note that read_buf is an internal instance variable. I allocate it
// there to avoid constant reallocation overhead for applications that
// call this method in a loop at the cost of some unneeded overhead
// if this method is never called.
int bytes_read = read(read_buf, 0, read_buf.length);
if (bytes_read == -1)
return(-1);
else
return((read_buf[0] & 0xFF));
}
/*************************************************************************/
/**
* This method reads bytes from the stream into a caller supplied buffer.
* It starts storing bytes at position <code>offset</code> into the buffer and
* reads a maximum of <cod>>len</code> bytes. Note that this method can actually
* read fewer than <code>len</code> bytes. The actual number of bytes read is
* returned. A -1 is returned to indicated that no bytes can be read
* because the end of the stream was reached. If the stream is already
* closed, a -1 will again be returned to indicate the end of the stream.
* <p>
* This method will block if no bytes are available to be read.
*
* @param buf The buffer into which bytes will be stored
* @param offset The index into the buffer at which to start writing.
* @param len The maximum number of bytes to read.
*/
public synchronized int
read(byte[] buf, int offset, int len) throws IOException
{
if (!ever_connected)
throw new IOException("Not connected");
int bytes_read = 0;
for (;;)
{ {
src.connect(this); // If there are bytes, take them
} if (in != -1)
catch (IOException ex)
{ {
po = null; int desired_bytes = len - bytes_read;
throw ex;
}
}
public synchronized int read() throws IOException // We are in a "wrap" condition
if (out > in)
{
if (desired_bytes > (pipe_size - out))
{ {
// TBD: Spec says to throw IOException if thread writing to output stream if (in == 0)
// died. What does this really mean? Theoretically, multiple threads desired_bytes = (pipe_size - out) - 1;
// could be writing to this object. Do you track the first, last, or
// all of them?
if (po == null)
if (buffer == null)
throw new IOException("pipe closed");
else else
throw new IOException("pipe unconnected"); desired_bytes = pipe_size - out;
// Block until there's something to read or output stream was closed. System.arraycopy(buffer, out, buf, offset + bytes_read,
while (in < 0) desired_bytes);
try
{ bytes_read += desired_bytes;
if (outClosed) out += desired_bytes;
return -1; desired_bytes = len - bytes_read;
wait();
if (out == pipe_size)
out = 0;
notifyAll();
} }
catch (InterruptedException ex) else
{ {
throw new InterruptedIOException(); if ((out + desired_bytes) == in)
} --desired_bytes;
// Let other threads know there's room to write now. if (((out + desired_bytes) == pipe_size) && (in == 0))
notifyAll(); desired_bytes = (pipe_size - out) - 1;
System.arraycopy(buffer, out, buf, offset + bytes_read,
desired_bytes);
int retval = buffer[out++] & 0xFF; bytes_read += desired_bytes;
out += desired_bytes;
desired_bytes = len - bytes_read;
// Wrap back around if at end of the array. if (out == pipe_size)
if (out >= buffer.length)
out = 0; out = 0;
// When the last byte available is read, mark the buffer as empty. notifyAll();
if (out == in) }
}
// We are in a "no wrap" or condition (can also be fall through
// from above
if (in > out)
{ {
in = -1; if (desired_bytes >= ((in - out) - 1))
desired_bytes = (in - out) - 1;
System.arraycopy(buffer, out, buf, offset + bytes_read,
desired_bytes);
bytes_read += desired_bytes;
out += desired_bytes;
desired_bytes = len - bytes_read;
if (out == pipe_size)
out = 0; out = 0;
}
return retval; notifyAll();
}
} }
public synchronized int read(byte[] b, int off, int len) throws IOException // If we are done, return
if (bytes_read == len)
return(bytes_read);
// Return a short count if necessary
if (bytes_read < len)
if (try_not_to_block)
return(bytes_read);
// Handle the case where the end of stream was encountered.
if (closed)
{
// We never let in == out so there might be one last byte
// available that we have not copied yet.
if (in != -1)
{ {
if (off < 0 || len < 0 || off + len > b.length) buf[offset + bytes_read] = buffer[out];
throw new ArrayIndexOutOfBoundsException(); in = -1;
++out;
++bytes_read;
}
// TBD: Spec says to throw IOException if thread writing to output stream if (bytes_read != 0)
// died. What does this really mean? Theoretically, multiple threads return(bytes_read);
// could be writing to this object. Do you track the first, last, or
// all of them?
if (po == null)
if (buffer == null)
throw new IOException("pipe closed");
else else
throw new IOException("pipe unconnected"); return(-1);
}
// Block until there's something to read or output stream was closed. // Wait for a byte to be read
while (in < 0)
try try
{ {
if (outClosed)
return -1;
wait(); wait();
} }
catch (InterruptedException ex) catch(InterruptedException e) { ; }
}
}
/*************************************************************************/
/**
* This method receives a byte of input from the source PipedOutputStream.
* If there is no data ready to be written, or if the internal circular
* buffer is full, this method blocks.
*
* *****What is this method really supposed to do *********
*/
protected synchronized void
receive(int byte_received) throws IOException
{
int orig_in = in;
for (;;)
{ {
throw new InterruptedIOException(); // Wait for something to happen
try
{
wait();
} }
catch(InterruptedException e) { ; }
// Let other threads know there's room to write now. // See if we woke up because the stream was closed on us
notifyAll(); if (closed)
throw new IOException("Stream closed before receiving byte");
int numRead; // See if a byte of data was received
len = Math.min(len, available()); if (in != orig_in)
if (in <= out && len >= (numRead = buffer.length - out)) return;
{
// Buffer has wrapped around; need to copy in 2 steps.
// Copy to the end of the buffer first; second copy may be of zero
// bytes but that is ok. Doing it that way saves having to check
// later if 'out' has grown to buffer.length.
System.arraycopy(buffer, out, b, off, numRead);
len -= numRead;
off += numRead;
out = 0;
} }
else }
numRead = 0;
/*************************************************************************/
System.arraycopy(buffer, out, b, off, len); /**
numRead += len; * This method is used by the connected <code>PipedOutputStream</code> to
out += len; * write bytes into the buffer. It uses this method instead of directly
* writing the bytes in order to obtain ownership of the object's monitor
* for the purposes of calling <code>notify</code>.
*
* @param buf The array containing bytes to write to this stream
* @param offset The offset into the array to start writing from
* @param len The number of bytes to write.
*
* @exception IOException If an error occurs
*/
synchronized void
write(byte[] buf, int offset, int len) throws IOException
{
if (len <= 0)
return;
// When the last byte available is read, mark the buffer as empty. int total_written = 0;
if (out == in) while (total_written < len)
{ {
in = -1; // If we are not at the end of the buffer with out = 0
out = 0; if (!((in == (buffer.length - 1)) && (out == 0)))
} {
// This is the "no wrap" situation
if ((in - 1) >= out)
{
int bytes_written = 0;
if ((buffer.length - in) > (len - total_written))
bytes_written = (len - total_written);
else if (out == 0)
bytes_written = (buffer.length - in) - 1;
else
bytes_written = (buffer.length - in);
return numRead; if (bytes_written > 0)
} System.arraycopy(buf, offset + total_written, buffer, in,
bytes_written);
total_written += bytes_written;
in += bytes_written;
if (in == buffer.length)
in = 0;
protected synchronized void receive(int b) throws IOException notifyAll();
}
// This is the "wrap" situtation
if ((out > in) && (total_written != len))
{ {
if (buffer == null) int bytes_written = 0;
throw new IOException("pipe closed");
// TBD: Spec says to throw IOException if thread reading from input stream // Do special processing if we are at the beginning
// died. What does this really mean? Theoretically, multiple threads if (in == -1)
// could be reading to this object (why else would 'read' be synchronized?). {
// Do you track the first, last, or all of them? in = 0;
if (b < 0) if (buffer.length > len)
bytes_written = len;
else
bytes_written = buffer.length - 1;
}
else if (((out - in) - 1) < (len - total_written))
{ {
outClosed = true; bytes_written = (out - in) - 1;
notifyAll(); // In case someone was blocked in a read. }
return; else
{
bytes_written = len - total_written;
} }
// Block until there's room in the pipe. // If the buffer is full, wait for it to empty out
while (in == out) if ((out - 1) == in)
{
try try
{ {
wait(); wait();
} }
catch (InterruptedException ex) catch (InterruptedException e)
{ {
throw new InterruptedIOException(); continue;
}
} }
// Check if buffer is empty. System.arraycopy(buf, offset + total_written, buffer, in,
if (in < 0) bytes_written);
in = 0; total_written += bytes_written;
in += bytes_written;
buffer[in++] = (byte) b;
// Wrap back around if at end of the array. if (in == buffer.length)
if (in >= buffer.length)
in = 0; in = 0;
// Let other threads know there's something to read when this returns.
notifyAll(); notifyAll();
} }
}
// Wait for some reads to occur before we write anything.
else
{
try
{
wait();
}
catch (InterruptedException e) { ; }
}
}
} }
} // class PipedInputStream
libjava/java/io/PipedOutputStream.java
// PipedOutputStream.java - Write bytes to a pipe. /* PipedOutputStream.java -- Write portion of piped streams.
Copyright (C) 1998 Free Software Foundation, Inc.
/* Copyright (C) 1998, 1999, 2000 Free Software Foundation This file is part of GNU Classpath.
This file is part of libgcj. GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU Classpath 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 for more details.
You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.
As a special exception, if you link this library with other files to
produce an executable, this library does not by itself cause the
resulting executable to be covered by the GNU General Public License.
This exception does not however invalidate any other reasons why the
executable file might be covered by the GNU General Public License. */
This software is copyrighted work licensed under the terms of the
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
details. */
package java.io; package java.io;
/** /**
* @author Tom Tromey <tromey@cygnus.com> * This class writes its bytes to a <code>PipedInputStream</code> to
* @date September 24, 1998 * which it is connected.
* <p>
* It is highly recommended that a <code>PipedOutputStream</code> and its
* connected <code>PipedInputStream</code> be in different threads. If
* they are in the same thread, read and write operations could deadlock
* the thread.
*
* @version 0.0
*
* @author Aaron M. Renn (arenn@urbanophile.com)
*/ */
public class PipedOutputStream extends OutputStream
{
/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3 /*************************************************************************/
* "The Java Language Specification", ISBN 0-201-63451-1
* Status: Believed complete and correct. /*
* Instance Variables
*/ */
public class PipedOutputStream extends OutputStream /**
* This is the <code>PipedInputStream</code> to which this object
* is connected.
*/
private PipedInputStream snk;
/**
* This flag indicates whether or not this stream has ever been
* connected to an input stream
*/
private boolean ever_connected;
/**
* This flag indicates whether the <code>close</code> method has ever
* been called for this stream.
*/
private boolean closed;
/*************************************************************************/
/**
* This method initializes a new <code>PipedOutputStream</code> instance.
* This constructor creates an unconnected object. It must be connected
* to a <code>PipedInputStream</code> object using the <code>connect</code>
* method prior to writing any data or an exception will be thrown.
*/
public
PipedOutputStream()
{ {
public void close () throws IOException ; // Do Nothing
{ }
closed = true;
// Notify PipedInputStream that there is no more data to be had. /*************************************************************************/
destination.receive(-1);
}
public void connect (PipedInputStream dest) throws IOException /**
{ * This method initializes a new <code>PipedOutputStream</code> instance
if (closed) * to write to the specified <code>PipedInputStream</code>. This stream
throw new IOException("pipe closed"); * is then ready for writing.
*
* @param snk The <code>PipedInputStream</code> to connect this stream to.
*
* @exception IOException If an error occurs
*/
public
PipedOutputStream(PipedInputStream snk) throws IOException
{
connect(snk);
}
/*************************************************************************/
/*
* Instance Methods
*/
if (destination != null) /**
if (destination == dest) * This method connects this object to the specified
* <code>PipedInputStream</code> object. This stream will then be ready
* for writing. If this stream is already connected or has been
* previously closed, then an exception is thrown.
*
* @param snk The <code>PipedInputStream</code> to connect this stream to
*
* @exception IOException If an error occurs
*/
public synchronized void
connect(PipedInputStream snk) throws IOException
{
if (snk == this.snk)
return; return;
else
throw new IOException("pipe already connected");
destination = dest;
try
{
dest.connect(this);
}
catch (IOException ex)
{
destination = null;
throw ex;
}
}
public synchronized void flush () throws IOException
{
// There doesn't seem to be anything to do here.
// TBD: Should this maybe do a notifyAll as a way for the user
// to wake up the input stream to check for bytes to read? Shouldn't
// be necessary but if there aren't any bytes, other threads will just
// go blocak again anyway so it wouldn't hurt.
}
public PipedOutputStream ()
{
closed = false;
}
public PipedOutputStream (PipedInputStream dest) throws IOException
{
closed = false;
connect (dest);
}
public void write (int oneByte) throws IOException
{
if (closed)
throw new IOException ();
destination.receive(oneByte);
}
public void write (byte[] buffer, int offset, int count) throws IOException if (ever_connected)
{ throw new IOException("Already connected");
if (closed) if (closed)
throw new IOException (); throw new IOException("Stream is closed and cannot be reopened");
if (offset < 0 || count < 0 || offset + count > buffer.length)
throw new ArrayIndexOutOfBoundsException (); this.snk = snk;
for (int i = 0; i < count; ++i) ever_connected = true;
destination.receive (buffer[offset + i]); snk.src = this;
}
snk.connect(this);
// Instance variables. }
private PipedInputStream destination;
private boolean closed; /*************************************************************************/
/**
* This method closes this stream so that no more data can be written
* to it. Any further attempts to write to this stream may throw an
* exception
*
* @exception IOException If an error occurs
*/
public synchronized void
close() throws IOException
{
closed = true;
snk.close();
notifyAll();
}
/*************************************************************************/
/**
* This method writes a single byte of date to the stream. Note that
* this method will block if the <code>PipedInputStream</code> to which
* this object is connected has a full buffer.
*
* @param b The byte of data to be written, passed as an <code>int</code>.
*
* @exception IOException If an error occurs
*/
public synchronized void
write(int b) throws IOException
{
byte[] buf = new byte[1];
buf[0] = (byte)(b & 0xFF);
snk.write(buf, 0, buf.length);
}
/*************************************************************************/
/**
* This method writes <code>len</code> bytes of data from the byte array
* <code>buf</code> starting at index <code>offset</code> in the array
* to the stream. Note that this method will block if the
* <code>PipedInputStream</code> to which this object is connected has
* a buffer that cannot hold all of the bytes to be written.
*
* @param buf The array containing bytes to write to thes stream.
* @param offset The index into the array to start writing bytes from.
* @param len The number of bytes to write.
*
* @exception IOException If an error occurs
*/
public void
write(byte[] buf, int offset, int len) throws IOException
{
snk.write(buf, 0, len);
}
/*************************************************************************/
/**
* This method flushes any unwritten bytes to the output and notifies
* any waiting readers that the pipe is ready to be read.
*
* @exception IOException If an error occurs.
*/
public void
flush() throws IOException
{
return;
} }
} // class PipedOutputStream
libjava/java/io/PipedReader.java
// PipedReader.java - Piped character stream. /* PipedReader.java -- Input stream that reads from an output stream
Copyright (C) 1998, 1999 Free Software Foundation, Inc.
/* Copyright (C) 1998, 1999 Free Software Foundation This file is part of GNU Classpath.
This file is part of libgcj. GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU Classpath 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 for more details.
You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.
As a special exception, if you link this library with other files to
produce an executable, this library does not by itself cause the
resulting executable to be covered by the GNU General Public License.
This exception does not however invalidate any other reasons why the
executable file might be covered by the GNU General Public License. */
This software is copyrighted work licensed under the terms of the
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
details. */
package java.io; package java.io;
/** /**
* @author Tom Tromey <tromey@cygnus.com> * This class is an input stream that reads its chars from an output stream
* @date September 25, 1998 * to which it is connected.
* <p>
* Data is read and written to an internal buffer. It is highly recommended
* that the <code>PipedReader</code> and connected <code>PipedWriter</code>
* be part of different threads. If they are not, there is a possibility
* that the read and write operations could deadlock their thread.
*
* @version 0.0
*
* @author Aaron M. Renn (arenn@urbanophile.com)
*/
public class PipedReader extends Reader
{
/*************************************************************************/
/*
* Class Variables
*/ */
/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3 /**
* "The Java Language Specification", ISBN 0-201-63451-1 * The size of the internal buffer used for input/output. Note that this
* Status: Complete to 1.1. * can be overriden by setting the system property
* <code>gnu.java.io.PipedReader.pipe_size</code> to the desired size shown
* in chars. This is not a standard part of the class library. Note that
* since this variable is <code>final</code>, it cannot be changed to refect
* the size specified in the property.
* <p>
* The value for this variable is 2048.
*/ */
private static final int PIPE_SIZE = 2048;
public class PipedReader extends Reader /**
* This is the real pipe size. It defaults to PIPE_SIZE, unless overridden
* by use of the system property <code>gnu.java.io.PipedReader.pipe_size</code>.
*/
private static int pipe_size;
/**
* This variable indicates whether or not the <code>read()</code> method will attempt
* return a short count if this will possibly keep the stream from blocking.
* The default for this is <code>false</code> because that is what what the JDK seems
* to imply in its javadocs. We set this to <code>false</code> if the system
* property <code>gnu.java.io.try_not_to_block</code> is set.
*/
private static boolean try_not_to_block = false;
static
{ {
public void close () throws IOException pipe_size = Integer.getInteger("gnu.java.io.PipedReader.pipe_size",
{ PIPE_SIZE).intValue();
String block_prop = System.getProperty("gnu.java.io.try_not_to_block");
if (block_prop != null)
try_not_to_block = true;
}
/*************************************************************************/
/*
* Instance Variables
*/
/**
* This is the internal circular buffer used for storing chars written
* to the pipe and from which chars are read by this stream
*/
private char[] buffer = new char[pipe_size];
/**
* The index into buffer where the chars written char the connected
* <code>PipedWriter</code> will be written. If this variables is less
* than 0, then the buffer is empty. If this variable is equal to
* <code>out</code>, then the buffer is full
*/
private int in = -1;
/**
* This index into the buffer where chars will be read from.
*/
private int out = 0;
/**
* This variable is <code>true</code> if this object has ever been connected
* to a <code>PipedWriter</code>, and <code>false</code> otherwise. It is used
* to detect an attempt to connect an already connected stream or to
* otherwise use the stream before it is connected.
*/
private boolean ever_connected = false;
/**
* This variable is set to <code>true</code> if the <code>close()</code> method is
* called. This value is checked prevents a caller from re-opening the
* stream.
*/
private boolean closed = false;
/**
* This variable is the PipedWriter to which this stream is connected.
*/
PipedWriter src;
/*************************************************************************/
/*
* Constructors
*/
/**
* This constructor creates a new <code>PipedReader</code> that is not
* connected to a <code>PipedWriter</code>. It must be connected before
* chars can be read from this stream.
*/
public
PipedReader()
{
return;
}
/*************************************************************************/
/**
* This constructor creates a new <code>PipedReader</code> and connects
* it to the passed in <code>PipedWriter</code>. The stream is then read
* for reading.
*
* @param src The <code>PipedWriter</code> to connect this stream to
*
* @exception IOException If an error occurs
*/
public
PipedReader(PipedWriter src) throws IOException
{
connect(src);
}
/*************************************************************************/
/*
* Instance Variables
*/
/**
* This method connects this stream to the passed in <code>PipedWriter</code>.
* This stream is then ready for reading. If this stream is already
* connected or has been previously closed, then an exception is thrown
*
* @param src The <code>PipedWriter</code> to connect this stream to
*
* @exception IOException If an error occurs
*/
public void
connect(PipedWriter src) throws IOException
{
if (src == this.src)
return;
if (ever_connected)
throw new IOException("Already connected");
if (closed)
throw new IOException("Stream is closed and cannot be reopened");
synchronized (lock) {
src.connect(this);
ever_connected = true;
} // synchronized
}
/*************************************************************************/
/**
* This methods closes the stream so that no more data can be read
* from it.
*
* @exception IOException If an error occurs
*/
public void
close() throws IOException
{
synchronized (lock) {
closed = true; closed = true;
} notifyAll();
} // synchronized
}
/*************************************************************************/
/**
* This method determines whether or not this stream is ready to be read.
* If this metho returns <code>false</code> an attempt to read may (but is
* not guaranteed to) block.
*
* @return <code>true</code> if this stream is ready to be read, <code>false</code> otherwise
*
* @exception IOException If an error occurs
*/
public boolean
ready() throws IOException
{
if (in == -1)
return(false);
if (out == (in - 1))
return(false);
if ((out == pipe_size) && (in == 0))
return(false);
return(true);
}
/*************************************************************************/
/**
* This method reads a single char from the pipe and returns it as an
* <code>int</code>.
* <p>
* This method will block if no chars are available to be read.
*
* @return An char read from the pipe, or -1 if the end of stream is
* reached.
*
* @exception IOException If an error occurs.
*/
public int
read() throws IOException
{
char[] buf = new char[1];
public void connect (PipedWriter src) throws IOException return(read(buf, 0, buf.length));
}
/*************************************************************************/
/**
* This method reads chars from the stream into a caller supplied buffer.
* It starts storing chars at position <code>offset</code> into the buffer and
* reads a maximum of <cod>>len</code> chars. Note that this method can actually
* read fewer than <code>len</code> chars. The actual number of chars read is
* returned. A -1 is returned to indicated that no chars can be read
* because the end of the stream was reached. If the stream is already
* closed, a -1 will again be returned to indicate the end of the stream.
* <p>
* This method will block if no chars are available to be read.
*
* @param buf The buffer into which chars will be stored
* @param offset The index into the buffer at which to start writing.
* @param len The maximum number of chars to read.
*/
public int
read(char[] buf, int offset, int len) throws IOException
{
if (!ever_connected)
throw new IOException("Not connected");
synchronized (lock) {
int chars_read = 0;
for (;;)
{ {
if (closed) // If there are chars, take them
throw new IOException ("already closed"); if (in != -1)
if (writer != null)
{ {
if (writer == src) int desired_chars = len - chars_read;
return;
throw new IOException ("already connected"); // We are in a "wrap" condition
} if (out > in)
try {
if (desired_chars > (pipe_size - out))
{ {
writer = src; if (in == 0)
writer.connect(this); desired_chars = (pipe_size - out) - 1;
else
desired_chars = pipe_size - out;
System.arraycopy(buffer, out, buf, offset + chars_read,
desired_chars);
chars_read += desired_chars;
out += desired_chars;
desired_chars = len - chars_read;
if (out == pipe_size)
out = 0;
notifyAll();
} }
catch (IOException e) else
{ {
writer = null; if ((out + desired_chars) == in)
throw e; --desired_chars;
if (((out + desired_chars) == pipe_size) && (in == 0))
desired_chars = (pipe_size - out) - 1;
System.arraycopy(buffer, out, buf, offset + chars_read,
desired_chars);
chars_read += desired_chars;
out += desired_chars;
desired_chars = len - chars_read;
if (out == pipe_size)
out = 0;
notifyAll();
} }
} }
public PipedReader () // We are in a "no wrap" or condition (can also be fall through
// from above
if (in > out)
{ {
super (); if (desired_chars >= ((in - out) - 1))
writer = null; desired_chars = (in - out) - 1;
closed = false;
in = -1; System.arraycopy(buffer, out, buf, offset + chars_read,
desired_chars);
chars_read += desired_chars;
out += desired_chars;
desired_chars = len - chars_read;
if (out == pipe_size)
out = 0; out = 0;
pipeBuffer = new char[1024];
notifyAll();
}
} }
public PipedReader (PipedWriter src) throws IOException // If we are done, return
if (chars_read == len)
return(chars_read);
// Return a short count if necessary
if (chars_read < len)
if (try_not_to_block)
return(chars_read);
// Handle the case where the end of stream was encountered.
if (closed)
{ {
super (); // We never let in == out so there might be one last char
closed = false; // available that we have not copied yet.
if (in != -1)
{
buf[offset + chars_read] = buffer[out];
in = -1; in = -1;
out = 0; ++out;
pipeBuffer = new char[1024]; ++chars_read;
connect (src);
} }
public int read (char buf[], int offset, int count) throws IOException if (chars_read != 0)
{ return(chars_read);
if (closed) else
throw new IOException ("closed"); return(-1);
if (count < 0) }
throw new ArrayIndexOutOfBoundsException ();
int toCopy = count; // Wait for a char to be read
synchronized (lock) try
{ {
while (toCopy > 0) wait();
}
catch(InterruptedException e) { ; }
}
} // synchronized
}
/*************************************************************************/
/**
* This method is used by the connected <code>PipedWriter</code> to
* write chars into the buffer. It uses this method instead of directly
* writing the chars in order to obtain ownership of the object's monitor
* for the purposes of calling <code>notify</code>.
*
* @param buf The array containing chars to write to this stream
* @param offset The offset into the array to start writing from
* @param len The number of chars to write.
*
* @exception IOException If an error occurs
*/
void
write(char[] buf, int offset, int len) throws IOException
{
if (len <= 0)
return;
synchronized (lock) {
int total_written = 0;
while (total_written < len)
{ {
// Wait for data in the pipe. If the writer is closed and // If we are not at the end of the buffer with out = 0
// no data has been copied into the output buffer, return if (!((in == (buffer.length - 1)) && (out == 0)))
// the magic EOF number.
while (in == -1)
{ {
if (writer.isClosed()) // This is the "no wrap" situation
if ((in - 1) >= out)
{ {
if (toCopy < count) int chars_written = 0;
return count - toCopy; if ((buffer.length - in) > (len - total_written))
return -1; chars_written = (len - total_written);
else if (out == 0)
chars_written = (buffer.length - in) - 1;
else
chars_written = (buffer.length - in);
if (chars_written > 0)
System.arraycopy(buf, offset + total_written, buffer, in,
chars_written);
total_written += chars_written;
in += chars_written;
if (in == buffer.length)
in = 0;
notifyAll();
} }
// This is the "wrap" situtation
if ((out > in) && (total_written != len))
{
int chars_written = 0;
// Note that JCL doesn't say this is the right thing // Do special processing if we are at the beginning
// to do. Still, it feels right, and we must deal if (in == -1)
// with an interrupt somehow.
try
{ {
lock.wait(); in = 0;
if (buffer.length > len)
chars_written = len;
else
chars_written = buffer.length - 1;
} }
catch (InterruptedException e) else if (((out - in) - 1) < (len - total_written))
{ {
InterruptedIOException io chars_written = (out - in) - 1;
= new InterruptedIOException (e.getMessage());
io.bytesTransferred = count - toCopy;
throw io;
} }
}
// Now copy some data from pipe into user buffer.
int len;
if (in < out)
len = pipeBuffer.length - out;
else else
len = in - out; {
len = len > toCopy ? toCopy : len; chars_written = len - total_written;
System.arraycopy(pipeBuffer, out, buf, offset, len);
out += len;
if (out == pipeBuffer.length)
out = 0;
toCopy -= len;
offset += len;
// If we've read all the data, then reset so that we know
// there is nothing left to be read.
if (in == out)
in = -1;
// Tell anybody waiting for space in the buffer.
lock.notifyAll();
}
}
return count;
} }
void receive (char buf[], int offset, int count) throws IOException // If the buffer is full, wait for it to empty out
{ if ((out - 1) == in)
if (count < 0)
throw new ArrayIndexOutOfBoundsException ();
int original = count;
synchronized (lock)
{
while (count > 0)
{
// Wait until there is some space in the buffer.
while (in == out)
{ {
try try
{ {
lock.wait(); wait();
} }
catch (InterruptedException e) catch (InterruptedException e)
{ {
// Turn interrupts into IO interrupts. continue;
InterruptedIOException io
= new InterruptedIOException (e.getMessage());
io.bytesTransferred = original - count;
throw io;
} }
} }
// Compute destination in the pipe. System.arraycopy(buf, offset + total_written, buffer, in,
int base, len; chars_written);
if (in == -1) total_written += chars_written;
{ in += chars_written;
base = 0;
len = pipeBuffer.length; if (in == buffer.length)
in = 0;
notifyAll();
} }
else if (in < out)
{
base = in;
len = out - in;
} }
// Wait for some reads to occur before we write anything.
else else
{ {
base = in; try
len = pipeBuffer.length - in; {
} wait();
int copyLen = len > count ? count : len;
// Copy data and update local state.
System.arraycopy(buf, offset, pipeBuffer, base, copyLen);
in = base + copyLen;
if (in == pipeBuffer.length)
in = 0;
count -= copyLen;
offset += copyLen;
// Tell anybody waiting for data.
lock.notifyAll();
} }
catch (InterruptedException e) { ; }
} }
} }
} // synchronized
}
} // class PipedReader
boolean isClosed ()
{
return closed;
}
// The associated writer.
private PipedWriter writer;
// True if this reader has been closed.
boolean closed;
// Index of next character to overwrite when receive() is called.
// If -1, then that means the buffer is empty.
private int in;
// Index of next character to return from read().
private int out;
// The pipe buffer itself.
private char[] pipeBuffer;
}
libjava/java/io/PipedWriter.java
// PipedWriter.java - Piped character stream. /* PipedWriter.java -- Write portion of piped streams.
Copyright (C) 1998 Free Software Foundation, Inc.
/* Copyright (C) 1998, 1999 Free Software Foundation This file is part of GNU Classpath.
This file is part of libgcj. GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU Classpath 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 for more details.
You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING. If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.
As a special exception, if you link this library with other files to
produce an executable, this library does not by itself cause the
resulting executable to be covered by the GNU General Public License.
This exception does not however invalidate any other reasons why the
executable file might be covered by the GNU General Public License. */
This software is copyrighted work licensed under the terms of the
Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
details. */
package java.io; package java.io;
/** /**
* @author Tom Tromey <tromey@cygnus.com> * This class writes its chars to a <code>PipedReader</code> to
* @date September 25, 1998 * which it is connected.
* <p>
* It is highly recommended that a <code>PipedWriter</code> and its
* connected <code>PipedReader</code> be in different threads. If
* they are in the same thread, read and write operations could deadlock
* the thread.
*
* @version 0.0
*
* @author Aaron M. Renn (arenn@urbanophile.com)
*/ */
public class PipedWriter extends Writer
{
/* 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. /*
* Instance Variables
*/ */
public class PipedWriter extends Writer /**
* This is the <code>PipedReader</code> to which this object
* is connected.
*/
private PipedReader snk;
/**
* This flag indicates whether or not this stream has ever been
* connected to an input stream
*/
private boolean ever_connected;
/**
* This flag indicates whether the <code>close</code> method has ever
* been called for this stream.
*/
private boolean closed;
/*************************************************************************/
/**
* This method initializes a new <code>PipedWriter</code> instance.
* This constructor creates an unconnected object. It must be connected
* to a <code>PipedReader</code> object using the <code>connect</code>
* method prior to writing any data or an exception will be thrown.
*/
public
PipedWriter()
{ {
public void close () throws IOException ; // Do Nothing
{ }
closed = true;
}
public void connect (PipedReader sink) throws IOException /*************************************************************************/
{
if (closed) /**
throw new IOException ("already closed"); * This method initializes a new <code>PipedWriter</code> instance
if (reader != null) * to write to the specified <code>PipedReader</code>. This stream
{ * is then ready for writing.
if (reader == sink) *
* @param snk The <code>PipedReader</code> to connect this stream to.
*
* @exception IOException If an error occurs
*/
public
PipedWriter(PipedReader snk) throws IOException
{
connect(snk);
}
/*************************************************************************/
/*
* Instance Methods
*/
/**
* This method connects this object to the specified
* <code>PipedReader</code> object. This stream will then be ready
* for writing. If this stream is already connected or has been
* previously closed, then an exception is thrown.
*
* @param snk The <code>PipedReader</code> to connect this stream to
*
* @exception IOException If an error occurs
*/
public void
connect(PipedReader snk) throws IOException
{
if (snk == this.snk)
return; return;
throw new IOException ("already connected");
} if (ever_connected)
try throw new IOException("Already connected");
{
reader = sink;
reader.connect(this);
}
catch (IOException e)
{
reader = null;
throw e;
}
}
public void flush () throws IOException
{
// We'll throw an exception if we're closed, but there's nothing
// else to do here.
if (closed)
throw new IOException ("closed");
}
public PipedWriter ()
{
super ();
closed = false;
}
public PipedWriter (PipedReader sink) throws IOException
{
super ();
closed = false;
connect (sink);
}
public void write (char buffer[], int offset, int count) throws IOException
{
if (closed) if (closed)
throw new IOException ("closed"); throw new IOException("Stream is closed and cannot be reopened");
reader.receive(buffer, offset, count);
} synchronized (lock) {
boolean isClosed () this.snk = snk;
{ ever_connected = true;
return closed; snk.src = this;
}
snk.connect(this);
// The associated reader.
private PipedReader reader; } // synchronized
private boolean closed; }
/*************************************************************************/
/**
* This method closes this stream so that no more data can be written
* to it. Any further attempts to write to this stream may throw an
* exception
*
* @exception IOException If an error occurs
*/
public void
close() throws IOException
{
synchronized (lock) {
closed = true;
snk.close();
notifyAll();
} // synchronized
} }
/*************************************************************************/
/**
* This methods writes a single byte of data to the pipe. This call may
* block if the pipe is full.
*
* @param c The <code>char</code> to write, passed as an <code>int</code>.
*
* @exception IOException If an error occurs.
*/
public void
write(int c) throws IOException
{
char[] buf = new char[1];
buf[0] = (char)c;
write(buf, 0, buf.length);
}
/*************************************************************************/
/**
* This method writes <code>len</code> chars of data from the char array
* <code>buf</code> starting at index <code>offset</code> in the array
* to the stream. Note that this method will block if the
* <code>PipedReader</code> to which this object is connected has
* a buffer that cannot hold all of the chars to be written.
*
* @param buf The array containing chars to write to thes stream.
* @param offset The index into the array to start writing chars from.
* @param len The number of chars to write.
*
* @exception IOException If an error occurs
*/
public void
write(char[] buf, int offset, int len) throws IOException
{
snk.write(buf, 0, len);
}
/*************************************************************************/
/**
* This method flushes any unwritten chars to the underlying output
* sink. This method does nothing in this class because this class does
* not buffer any chars.
*
* @exception IOException If an error occurs
*/
public void
flush() throws IOException
{
; // Do Nothing
}
} // class PipedWriter
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment