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Java lang extensions for java6+, a supplement to , replacement of a Guava, commons-lang.
Core utilities, Collection utilities, IO utilities, Cache, Configuration library ...
package com.jn.langx.commandline;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import com.jn.langx.commandline.util.CommandLineDebugUtils;
/**
* Copies all data from an input stream to an output stream.
*/
public class StreamPumper implements Runnable {
/**
* the default size of the internal buffer for copying the streams
*/
private static final int DEFAULT_SIZE = 1024;
/**
* the input stream to pump from
*/
private final InputStream is;
/**
* the output stream to pmp into
*/
private final OutputStream os;
/**
* the size of the internal buffer for copying the streams
*/
private final int size;
/**
* was the end of the stream reached
*/
private boolean finished;
/**
* close the output stream when exhausted
*/
private final boolean closeWhenExhausted;
/**
* Create a new stream pumper.
*
* @param is input stream to read data from
* @param os output stream to write data to.
* @param closeWhenExhausted if true, the output stream will be closed when the input is exhausted.
*/
public StreamPumper(final InputStream is, final OutputStream os,
final boolean closeWhenExhausted) {
this.is = is;
this.os = os;
this.size = DEFAULT_SIZE;
this.closeWhenExhausted = closeWhenExhausted;
}
/**
* Create a new stream pumper.
*
* @param is input stream to read data from
* @param os output stream to write data to.
* @param closeWhenExhausted if true, the output stream will be closed when the input is exhausted.
* @param size the size of the internal buffer for copying the streams
*/
public StreamPumper(final InputStream is, final OutputStream os,
final boolean closeWhenExhausted, final int size) {
this.is = is;
this.os = os;
this.size = size > 0 ? size : DEFAULT_SIZE;
this.closeWhenExhausted = closeWhenExhausted;
}
/**
* Create a new stream pumper.
*
* @param is input stream to read data from
* @param os output stream to write data to.
*/
public StreamPumper(final InputStream is, final OutputStream os) {
this(is, os, false);
}
/**
* Copies data from the input stream to the output stream. Terminates as
* soon as the input stream is closed or an error occurs.
*/
public void run() {
synchronized (this) {
// Just in case this object is reused in the future
finished = false;
}
final byte[] buf = new byte[this.size];
int length;
try {
while ((length = is.read(buf)) > 0) {
os.write(buf, 0, length);
}
} catch (final Exception e) {
// nothing to do - happens quite often with watchdog
} finally {
if (closeWhenExhausted) {
try {
os.close();
} catch (final IOException e) {
final String msg = "Got exception while closing exhausted output stream";
CommandLineDebugUtils.handleException(msg, e);
}
}
synchronized (this) {
finished = true;
notifyAll();
}
}
}
/**
* Tells whether the end of the stream has been reached.
*
* @return true is the stream has been exhausted.
*/
public synchronized boolean isFinished() {
return finished;
}
/**
* This method blocks until the stream pumper finishes.
*
* @throws InterruptedException if any thread interrupted the current thread before or while the current thread was waiting for a
* notification.
* @see #isFinished()
*/
public synchronized void waitFor() throws InterruptedException {
while (!isFinished()) {
wait();
}
}
}