From 8d285042d388a7105e3b50a5f438a5cd5ecdb499 Mon Sep 17 00:00:00 2001 From: tromey Date: Fri, 21 Apr 2000 01:18:16 +0000 Subject: 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. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@33300 138bc75d-0d04-0410-961f-82ee72b054a4 --- libjava/java/io/PipedWriter.java | 279 ++++++++++++++++++++++++++++----------- 1 file changed, 204 insertions(+), 75 deletions(-) (limited to 'libjava/java/io/PipedWriter.java') diff --git a/libjava/java/io/PipedWriter.java b/libjava/java/io/PipedWriter.java index 7efed3976da..cc36acdf0d5 100644 --- a/libjava/java/io/PipedWriter.java +++ b/libjava/java/io/PipedWriter.java @@ -1,88 +1,217 @@ -// 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; /** - * @author Tom Tromey - * @date September 25, 1998 + * This class writes its chars to a PipedReader to + * which it is connected. + *

+ * It is highly recommended that a PipedWriter and its + * connected PipedReader 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 +{ + +/*************************************************************************/ + +/* + * Instance Variables */ -/* 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. +/** + * This is the PipedReader 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 close method has ever + * been called for this stream. + */ +private boolean closed; + +/*************************************************************************/ + +/** + * This method initializes a new PipedWriter instance. + * This constructor creates an unconnected object. It must be connected + * to a PipedReader object using the connect + * method prior to writing any data or an exception will be thrown. + */ +public +PipedWriter() +{ + ; // Do Nothing +} + +/*************************************************************************/ + +/** + * This method initializes a new PipedWriter instance + * to write to the specified PipedReader. This stream + * is then ready for writing. + * + * @param snk The PipedReader to connect this stream to. + * + * @exception IOException If an error occurs + */ +public +PipedWriter(PipedReader snk) throws IOException +{ + connect(snk); +} + +/*************************************************************************/ + +/* + * Instance Methods */ -public class PipedWriter extends Writer +/** + * This method connects this object to the specified + * PipedReader 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 PipedReader to connect this stream to + * + * @exception IOException If an error occurs + */ +public void +connect(PipedReader snk) throws IOException +{ + if (snk == this.snk) + return; + + if (ever_connected) + throw new IOException("Already connected"); + + if (closed) + throw new IOException("Stream is closed and cannot be reopened"); + + synchronized (lock) { + + this.snk = snk; + ever_connected = true; + snk.src = this; + + snk.connect(this); + + } // synchronized +} + +/*************************************************************************/ + +/** + * 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 { - public void close () throws IOException - { - closed = true; - } - - public void connect (PipedReader sink) throws IOException - { - if (closed) - throw new IOException ("already closed"); - if (reader != null) - { - if (reader == sink) - return; - throw new IOException ("already connected"); - } - try - { - 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) - throw new IOException ("closed"); - reader.receive(buffer, offset, count); - } - - boolean isClosed () - { - return closed; - } - - // The associated reader. - private PipedReader reader; - private boolean closed; + 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 char to write, passed as an int. + * + * @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 len chars of data from the char array + * buf starting at index offset in the array + * to the stream. Note that this method will block if the + * PipedReader 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 + -- cgit v1.2.3