- /*
- * Copyright 2004 The Apache Software Foundation
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
- package org.apache.tools.ant.util;
-
- import java.io.IOException;
- import java.io.OutputStream;
- import java.io.FilterOutputStream;
-
- /**
- * Manages a set of <CODE>OutputStream</CODE>s to
- * write to a single underlying stream, which is
- * closed only when the last "funnel"
- * has been closed.
- */
- public class OutputStreamFunneler {
-
- /**
- * Default timeout.
- * @see #setTimeout()
- */
- public static final long DEFAULT_TIMEOUT_MILLIS = 1000;
-
- private class Funnel extends OutputStream {
- private boolean closed = false;
-
- private Funnel() {
- synchronized (OutputStreamFunneler.this) {
- ++count;
- }
- }
-
- public void flush() throws IOException {
- synchronized (OutputStreamFunneler.this) {
- dieIfClosed();
- out.flush();
- }
- }
-
- public void write(int b) throws IOException {
- synchronized (OutputStreamFunneler.this) {
- dieIfClosed();
- out.write(b);
- }
- }
-
- public void write(byte[] b) throws IOException {
- synchronized (OutputStreamFunneler.this) {
- dieIfClosed();
- out.write(b);
- }
- }
-
- public void write(byte[] b, int off, int len) throws IOException {
- synchronized (OutputStreamFunneler.this) {
- dieIfClosed();
- out.write(b, off, len);
- }
- }
-
- public void close() throws IOException {
- release(this);
- }
- }
-
- private OutputStream out;
- private int count = 0;
- private boolean closed;
- private long timeoutMillis;
-
- /**
- * Create a new <CODE>OutputStreamFunneler</CODE> for
- * the specified <CODE>OutputStream</CODE>.
- * @param out <CODE>OutputStream</CODE>.
- */
- public OutputStreamFunneler(OutputStream out) {
- this(out, DEFAULT_TIMEOUT_MILLIS);
- }
-
- /**
- * Create a new <CODE>OutputStreamFunneler</CODE> for
- * the specified <CODE>OutputStream</CODE>, with the
- * specified timeout value.
- * @param out <CODE>OutputStream</CODE>.
- * @param timeoutMillis <CODE>long</CODE>.
- * @see #setTimeout()
- */
- public OutputStreamFunneler(OutputStream out, long timeoutMillis) {
- if (out == null) {
- throw new IllegalArgumentException(
- "OutputStreamFunneler.<init>: out == null");
- }
- this.out = out;
- this.closed = false; //as far as we know
- setTimeout(timeoutMillis);
- }
-
- /**
- * Set the timeout for this <CODE>OutputStreamFunneler</CODE>.
- * This is the maximum time that may elapse between the closure
- * of the last "funnel" and the next call to
- * <CODE>getOutputStream()</CODE> without closing the
- * underlying stream.
- * @param timeoutMillis <CODE>long</CODE> timeout value.
- */
- public synchronized void setTimeout(long timeoutMillis) {
- this.timeoutMillis = timeoutMillis;
- }
-
- /**
- * Get a "funnel" <CODE>OutputStream</CODE> instance to
- * write to this <CODE>OutputStreamFunneler</CODE>'s underlying
- * <CODE>OutputStream</CODE>.
- * @return <code>OutputStream</code>.
- */
- public synchronized OutputStream getFunnelInstance()
- throws IOException {
- dieIfClosed();
- try {
- return new Funnel();
- } finally {
- notifyAll();
- }
- }
-
- private synchronized void release(Funnel funnel) throws IOException {
- //ignore release of an already-closed funnel
- if (!funnel.closed) {
- try {
- if (timeoutMillis > 0) {
- try {
- wait(timeoutMillis);
- } catch (InterruptedException eyeEx) {
- //ignore
- }
- }
- if (--count == 0) {
- close();
- }
- } finally {
- funnel.closed = true;
- }
- }
- }
-
- private synchronized void close() throws IOException {
- try {
- dieIfClosed();
- out.close();
- } finally {
- closed = true;
- }
- }
-
- private synchronized void dieIfClosed() throws IOException {
- if (closed) {
- throw new IOException("The funneled OutputStream has been closed.");
- }
- }
-
- }