@@ -17,11 +17,13 @@
*/
package org.apache.tools.ant.taskdefs;
import org.apache.tools.ant.util.FileUtils;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.tools.ant.util.FileUtils ;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit ;
/**
* Copies all data from an input stream to an output stream.
@@ -34,7 +36,7 @@ public class StreamPumper implements Runnable {
private final InputStream is;
private final OutputStream os;
private volatile boolean finish ;
private volatile boolean askedToStop ;
private volatile boolean finished;
private final boolean closeWhenExhausted;
private boolean autoflush = false;
@@ -42,6 +44,7 @@ public class StreamPumper implements Runnable {
private int bufferSize = SMALL_BUFFER_SIZE;
private boolean started = false;
private final boolean useAvailable;
private PostStopHandle postStopHandle;
/**
* Create a new StreamPumper.
@@ -58,7 +61,6 @@ public class StreamPumper implements Runnable {
/**
* Create a new StreamPumper.
*
* <p><b>Note:</b> If you set useAvailable to true, you must
* explicitly invoke {@link #stop stop} or interrupt the
* corresponding Thread when you are done or the run method will
@@ -120,41 +122,29 @@ public class StreamPumper implements Runnable {
final byte[] buf = new byte[bufferSize];
int length;
try {
while (true) {
int length;
while (!this.askedToStop && !Thread.interrupted()) {
waitForInput(is);
if (finish || Thread.interrupted()) {
if (askedToStop || Thread.interrupted()) {
break;
}
length = is.read(buf);
if (length <= 0 || Thread.interrupted()) {
if (length < 0) {
// EOF
break;
}
os.write(buf, 0, length);
if (autoflush) {
os.flush();
}
if (finish) { //NOSONAR
break;
}
}
// On completion, drain any available data (which might be the first data available for quick executions)
if (finish) {
while ((length = is.available()) > 0) {
if (Thread.interrupted()) {
break;
}
length = is.read(buf, 0, Math.min(length, buf.length));
if (length <= 0) {
break;
}
if (length > 0) {
// we did read something, so write it out
os.write(buf, 0, length);
if (autoflush) {
os.flush();
}
}
}
os.flush();
this.doPostStop();
} catch (InterruptedException ie) {
// likely PumpStreamHandler trying to stop us
} catch (Exception e) {
@@ -166,7 +156,7 @@ public class StreamPumper implements Runnable {
FileUtils.close(os);
}
finished = true;
finish = false;
askedToStop = false;
synchronized (this) {
notifyAll();
}
@@ -206,6 +196,7 @@ public class StreamPumper implements Runnable {
/**
* Get the size in bytes of the read buffer.
*
* @return the int size of the read buffer.
*/
public synchronized int getBufferSize() {
@@ -225,19 +216,26 @@ public class StreamPumper implements Runnable {
* Note that it may continue to block on the input stream
* but it will really stop the thread as soon as it gets EOF
* or any byte, and it will be marked as finished.
* @return Returns a {@link PostStopHandle} for the callers to
* know if the status of post-stop activities, that happen, before this
* {@link StreamPumper} is actually finished
* @since Ant 1.6.3
* @since Ant 10.2.0 this method returns a {@link PostStopHandle}
*/
/*package*/ synchronized void stop() {
finish = true;
/*package*/
synchronized PostStopHandle stop() {
askedToStop = true;
postStopHandle = new PostStopHandle();
notifyAll();
return postStopHandle;
}
private static final long POLL_INTERVAL = 100;
private void waitForInput(InputStream is)
throws IOException, InterruptedException {
throws IOException, InterruptedException {
if (useAvailable) {
while (!finish && is.available() == 0) {
while (!askedToStop && is.available() == 0) {
if (Thread.interrupted()) {
throw new InterruptedException();
}
@@ -249,4 +247,66 @@ public class StreamPumper implements Runnable {
}
}
private void doPostStop() throws IOException {
try {
final byte[] buf = new byte[bufferSize];
int length;
// We were asked to stop, the contract allows us to do any non-blocking
// final bits of reads, before actually finishing. So we try and drain any (non-blocking) available
// data. We *don't* check the thread interrupt status, anymore, once we start draining this non-blocking
// available data, to allow us to cleanly write out any available data.
if (askedToStop) {
int bytesReadableWithoutBlocking;
while ((bytesReadableWithoutBlocking = is.available()) > 0) {
length = is.read(buf, 0, Math.min(bytesReadableWithoutBlocking, buf.length));
if (length <= 0) {
break;
}
os.write(buf, 0, length);
}
}
// this can potentially be blocking, but that's OK since our post stop activity is allowed to
// cleanup/flush any data and the PostStopHandle let's the caller control over how long they want
// this to go, before actually interrupting the thread
os.flush();
} finally {
if (this.postStopHandle != null) {
this.postStopHandle.latch.countDown();
this.postStopHandle.inPostStopTasks = false;
}
}
}
/**
* A handle that can be used after {@link #stop()} has been invoked to check if the
* {@link StreamPumper} is in the process of do some post-stop tasks (like flushing
* of streams), before finishing.
*/
final class PostStopHandle {
private boolean inPostStopTasks = true;
private final CountDownLatch latch = new CountDownLatch(1);
/**
* Returns true if the {@link StreamPumper} is doing post-stop tasks (like flushing of streams).
* Else returns false.
* @return
*/
boolean isInPostStopTasks() {
return inPostStopTasks;
}
/**
* Waits for a maximum of {@code timeout} time for the post-stop activities to complete.
*
* @param timeout The maximum amount of time to wait for the post-stop activities to complete
* @param timeUnit The unit of {@code timeout}
* @return Returns true if the post-stop activities completed within the specified {@code timeout}.
* Else returns false
* @throws InterruptedException If the current thread was interrupted while waiting
*/
boolean awaitPostStopCompletion(final long timeout, final TimeUnit timeUnit) throws InterruptedException {
return this.latch.await(timeout, timeUnit);
}
}
}
Jaikiran Pai