| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You 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.commons.exec; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.io.PipedOutputStream; |
| |
| import org.apache.commons.exec.util.DebugUtils; |
| |
| /** |
| * Copies standard output and error of sub-processes to standard output and error |
| * of the parent process. If output or error stream are set to null, any feedback |
| * from that stream will be lost. |
| * |
| * @version $Id$ |
| */ |
| public class PumpStreamHandler implements ExecuteStreamHandler { |
| |
| private static final long STOP_TIMEOUT_ADDITION = 2000L; |
| |
| private Thread outputThread; |
| |
| private Thread errorThread; |
| |
| private Thread inputThread; |
| |
| private final OutputStream out; |
| |
| private final OutputStream err; |
| |
| private final InputStream input; |
| |
| private InputStreamPumper inputStreamPumper; |
| |
| /** the timeout in ms the implementation waits when stopping the pumper threads */ |
| private long stopTimeout; |
| |
| /** the last exception being caught */ |
| private IOException caught = null; |
| |
| /** |
| * Construct a new <CODE>PumpStreamHandler</CODE>. |
| */ |
| public PumpStreamHandler() { |
| this(System.out, System.err); |
| } |
| |
| /** |
| * Construct a new <CODE>PumpStreamHandler</CODE>. |
| * |
| * @param outAndErr the output/error <CODE>OutputStream</CODE>. |
| */ |
| public PumpStreamHandler(final OutputStream outAndErr) { |
| this(outAndErr, outAndErr); |
| } |
| |
| /** |
| * Construct a new <CODE>PumpStreamHandler</CODE>. |
| * |
| * @param out the output <CODE>OutputStream</CODE>. |
| * @param err the error <CODE>OutputStream</CODE>. |
| */ |
| public PumpStreamHandler(final OutputStream out, final OutputStream err) { |
| this(out, err, null); |
| } |
| |
| /** |
| * Construct a new <CODE>PumpStreamHandler</CODE>. |
| * |
| * @param out the output <CODE>OutputStream</CODE>. |
| * @param err the error <CODE>OutputStream</CODE>. |
| * @param input the input <CODE>InputStream</CODE>. |
| */ |
| public PumpStreamHandler(final OutputStream out, final OutputStream err, final InputStream input) { |
| this.out = out; |
| this.err = err; |
| this.input = input; |
| } |
| |
| /** |
| * Set maximum time to wait until output streams are exchausted |
| * when {@link #stop()} was called. |
| * |
| * @param timeout timeout in milliseconds or zero to wait forever (default) |
| */ |
| public void setStopTimeout(final long timeout) { |
| this.stopTimeout = timeout; |
| } |
| |
| /** |
| * Set the <CODE>InputStream</CODE> from which to read the standard output |
| * of the process. |
| * |
| * @param is the <CODE>InputStream</CODE>. |
| */ |
| public void setProcessOutputStream(final InputStream is) { |
| if (out != null) { |
| createProcessOutputPump(is, out); |
| } |
| } |
| |
| /** |
| * Set the <CODE>InputStream</CODE> from which to read the standard error |
| * of the process. |
| * |
| * @param is the <CODE>InputStream</CODE>. |
| */ |
| public void setProcessErrorStream(final InputStream is) { |
| if (err != null) { |
| createProcessErrorPump(is, err); |
| } |
| } |
| |
| /** |
| * Set the <CODE>OutputStream</CODE> by means of which input can be sent |
| * to the process. |
| * |
| * @param os the <CODE>OutputStream</CODE>. |
| */ |
| public void setProcessInputStream(final OutputStream os) { |
| if (input != null) { |
| if (input == System.in) { |
| inputThread = createSystemInPump(input, os); |
| } else { |
| inputThread = createPump(input, os, true); |
| } |
| } else { |
| try { |
| os.close(); |
| } catch (final IOException e) { |
| final String msg = "Got exception while closing output stream"; |
| DebugUtils.handleException(msg, e); |
| } |
| } |
| } |
| |
| /** |
| * Start the <CODE>Thread</CODE>s. |
| */ |
| public void start() { |
| if (outputThread != null) { |
| outputThread.start(); |
| } |
| if (errorThread != null) { |
| errorThread.start(); |
| } |
| if (inputThread != null) { |
| inputThread.start(); |
| } |
| } |
| |
| /** |
| * Stop pumping the streams. When a timeout is specified it it is not guaranteed that the |
| * pumper threads are cleanly terminated. |
| */ |
| public void stop() throws IOException { |
| |
| if (inputStreamPumper != null) { |
| inputStreamPumper.stopProcessing(); |
| } |
| |
| stopThread(outputThread, stopTimeout); |
| stopThread(errorThread, stopTimeout); |
| stopThread(inputThread, stopTimeout); |
| |
| if (err != null && err != out) { |
| try { |
| err.flush(); |
| } catch (final IOException e) { |
| final String msg = "Got exception while flushing the error stream : " + e.getMessage(); |
| DebugUtils.handleException(msg, e); |
| } |
| } |
| |
| if (out != null) { |
| try { |
| out.flush(); |
| } catch (final IOException e) { |
| final String msg = "Got exception while flushing the output stream"; |
| DebugUtils.handleException(msg, e); |
| } |
| } |
| |
| if (caught != null) { |
| throw caught; |
| } |
| } |
| |
| /** |
| * Get the error stream. |
| * |
| * @return <CODE>OutputStream</CODE>. |
| */ |
| protected OutputStream getErr() { |
| return err; |
| } |
| |
| /** |
| * Get the output stream. |
| * |
| * @return <CODE>OutputStream</CODE>. |
| */ |
| protected OutputStream getOut() { |
| return out; |
| } |
| |
| /** |
| * Create the pump to handle process output. |
| * |
| * @param is the <CODE>InputStream</CODE>. |
| * @param os the <CODE>OutputStream</CODE>. |
| */ |
| protected void createProcessOutputPump(final InputStream is, final OutputStream os) { |
| outputThread = createPump(is, os); |
| } |
| |
| /** |
| * Create the pump to handle error output. |
| * |
| * @param is the <CODE>InputStream</CODE>. |
| * @param os the <CODE>OutputStream</CODE>. |
| */ |
| protected void createProcessErrorPump(final InputStream is, final OutputStream os) { |
| errorThread = createPump(is, os); |
| } |
| |
| /** |
| * Creates a stream pumper to copy the given input stream to the given |
| * output stream. When the 'os' is an PipedOutputStream we are closing |
| * 'os' afterwards to avoid an IOException ("Write end dead"). |
| * |
| * @param is the input stream to copy from |
| * @param os the output stream to copy into |
| * @return the stream pumper thread |
| */ |
| protected Thread createPump(final InputStream is, final OutputStream os) { |
| final boolean closeWhenExhausted = os instanceof PipedOutputStream ? true : false; |
| return createPump(is, os, closeWhenExhausted); |
| } |
| |
| /** |
| * Creates a stream pumper to copy the given input stream to the given |
| * output stream. |
| * |
| * @param is the input stream to copy from |
| * @param os the output stream to copy into |
| * @param closeWhenExhausted close the output stream when the input stream is exhausted |
| * @return the stream pumper thread |
| */ |
| protected Thread createPump(final InputStream is, final OutputStream os, final boolean closeWhenExhausted) { |
| final Thread result = new Thread(new StreamPumper(is, os, closeWhenExhausted), "Exec Stream Pumper"); |
| result.setDaemon(true); |
| return result; |
| } |
| |
| /** |
| * Stopping a pumper thread. The implementation actually waits |
| * longer than specified in 'timeout' to detect if the timeout |
| * was indeed exceeded. If the timeout was exceeded an IOException |
| * is created to be thrown to the caller. |
| * |
| * @param thread the thread to be stopped |
| * @param timeout the time in ms to wait to join |
| */ |
| protected void stopThread(final Thread thread, final long timeout) { |
| |
| if (thread != null) { |
| try { |
| if (timeout == 0) { |
| thread.join(); |
| } else { |
| final long timeToWait = timeout + STOP_TIMEOUT_ADDITION; |
| final long startTime = System.currentTimeMillis(); |
| thread.join(timeToWait); |
| if (!(System.currentTimeMillis() < startTime + timeToWait)) { |
| final String msg = "The stop timeout of " + timeout + " ms was exceeded"; |
| caught = new ExecuteException(msg, Executor.INVALID_EXITVALUE); |
| } |
| } |
| } catch (final InterruptedException e) { |
| thread.interrupt(); |
| } |
| } |
| } |
| |
| /** |
| * Creates a stream pumper to copy the given input stream to the given |
| * output stream. |
| * |
| * @param is the System.in input stream to copy from |
| * @param os the output stream to copy into |
| * @return the stream pumper thread |
| */ |
| private Thread createSystemInPump(final InputStream is, final OutputStream os) { |
| inputStreamPumper = new InputStreamPumper(is, os); |
| final Thread result = new Thread(inputStreamPumper, "Exec Input Stream Pumper"); |
| result.setDaemon(true); |
| return result; |
| } |
| } |