--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/io/PipedWriter.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,184 @@
+/*
+ * Copyright 1996-2006 Sun Microsystems, Inc. All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code 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
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.io;
+
+
+/**
+ * Piped character-output streams.
+ *
+ * @author Mark Reinhold
+ * @since JDK1.1
+ */
+
+public class PipedWriter extends Writer {
+
+ /* REMIND: identification of the read and write sides needs to be
+ more sophisticated. Either using thread groups (but what about
+ pipes within a thread?) or using finalization (but it may be a
+ long time until the next GC). */
+ private PipedReader sink;
+
+ /* This flag records the open status of this particular writer. It
+ * is independent of the status flags defined in PipedReader. It is
+ * used to do a sanity check on connect.
+ */
+ private boolean closed = false;
+
+ /**
+ * Creates a piped writer connected to the specified piped
+ * reader. Data characters written to this stream will then be
+ * available as input from <code>snk</code>.
+ *
+ * @param snk The piped reader to connect to.
+ * @exception IOException if an I/O error occurs.
+ */
+ public PipedWriter(PipedReader snk) throws IOException {
+ connect(snk);
+ }
+
+ /**
+ * Creates a piped writer that is not yet connected to a
+ * piped reader. It must be connected to a piped reader,
+ * either by the receiver or the sender, before being used.
+ *
+ * @see java.io.PipedReader#connect(java.io.PipedWriter)
+ * @see java.io.PipedWriter#connect(java.io.PipedReader)
+ */
+ public PipedWriter() {
+ }
+
+ /**
+ * Connects this piped writer to a receiver. If this object
+ * is already connected to some other piped reader, an
+ * <code>IOException</code> is thrown.
+ * <p>
+ * If <code>snk</code> is an unconnected piped reader and
+ * <code>src</code> is an unconnected piped writer, they may
+ * be connected by either the call:
+ * <blockquote><pre>
+ * src.connect(snk)</pre></blockquote>
+ * or the call:
+ * <blockquote><pre>
+ * snk.connect(src)</pre></blockquote>
+ * The two calls have the same effect.
+ *
+ * @param snk the piped reader to connect to.
+ * @exception IOException if an I/O error occurs.
+ */
+ public synchronized void connect(PipedReader snk) throws IOException {
+ if (snk == null) {
+ throw new NullPointerException();
+ } else if (sink != null || snk.connected) {
+ throw new IOException("Already connected");
+ } else if (snk.closedByReader || closed) {
+ throw new IOException("Pipe closed");
+ }
+
+ sink = snk;
+ snk.in = -1;
+ snk.out = 0;
+ snk.connected = true;
+ }
+
+ /**
+ * Writes the specified <code>char</code> to the piped output stream.
+ * If a thread was reading data characters from the connected piped input
+ * stream, but the thread is no longer alive, then an
+ * <code>IOException</code> is thrown.
+ * <p>
+ * Implements the <code>write</code> method of <code>Writer</code>.
+ *
+ * @param c the <code>char</code> to be written.
+ * @exception IOException if the pipe is
+ * <a href=PipedOutputStream.html#BROKEN> <code>broken</code></a>,
+ * {@link #connect(java.io.PipedReader) unconnected}, closed
+ * or an I/O error occurs.
+ */
+ public void write(int c) throws IOException {
+ if (sink == null) {
+ throw new IOException("Pipe not connected");
+ }
+ sink.receive(c);
+ }
+
+ /**
+ * Writes <code>len</code> characters from the specified character array
+ * starting at offset <code>off</code> to this piped output stream.
+ * This method blocks until all the characters are written to the output
+ * stream.
+ * If a thread was reading data characters from the connected piped input
+ * stream, but the thread is no longer alive, then an
+ * <code>IOException</code> is thrown.
+ *
+ * @param cbuf the data.
+ * @param off the start offset in the data.
+ * @param len the number of characters to write.
+ * @exception IOException if the pipe is
+ * <a href=PipedOutputStream.html#BROKEN> <code>broken</code></a>,
+ * {@link #connect(java.io.PipedReader) unconnected}, closed
+ * or an I/O error occurs.
+ */
+ public void write(char cbuf[], int off, int len) throws IOException {
+ if (sink == null) {
+ throw new IOException("Pipe not connected");
+ } else if ((off | len | (off + len) | (cbuf.length - (off + len))) < 0) {
+ throw new IndexOutOfBoundsException();
+ }
+ sink.receive(cbuf, off, len);
+ }
+
+ /**
+ * Flushes this output stream and forces any buffered output characters
+ * to be written out.
+ * This will notify any readers that characters are waiting in the pipe.
+ *
+ * @exception IOException if the pipe is closed, or an I/O error occurs.
+ */
+ public synchronized void flush() throws IOException {
+ if (sink != null) {
+ if (sink.closedByReader || closed) {
+ throw new IOException("Pipe closed");
+ }
+ synchronized (sink) {
+ sink.notifyAll();
+ }
+ }
+ }
+
+ /**
+ * Closes this piped output stream and releases any system resources
+ * associated with this stream. This stream may no longer be used for
+ * writing characters.
+ *
+ * @exception IOException if an I/O error occurs.
+ */
+ public void close() throws IOException {
+ closed = true;
+ if (sink != null) {
+ sink.receivedLast();
+ }
+ }
+}