CommandLine.java

	private CommandLine(String command,
	                    OutputStream err,
	                    OutputStream out,
	                    boolean redirect,
	                    int buffer) throws IOException {
		this.buffer = buffer;
		
		executor = newFixedThreadPool(redirect ? 1 : 2);
		
		process = new ProcessBuilder(command)
				.redirectErrorStream(redirect)
				.start();
		
		if (out != null)
			this.out = pipe(process.getInputStream(), out);
		
		if (err != null)
			this.err = pipe(process.getErrorStream(), err);
	}
	
	public ExecutorService getExecutor() {
		return executor;
	}
	
	public Process getProcess() {
		return process;
	}
	
	public CommandLine execute(String... commands) {
		return execute(() -> new Iterator<String>() {
			int index = 0;
			
			@Override
			public boolean hasNext() {
				return index < commands.length;
			}
			
			@Override
			public String next() {
				return commands[index++];
			}
		});
	}
	
	public CommandLine execute(Iterable<String> commands) {
		try {
			for (String line : commands) {
				process.getOutputStream().write(line.getBytes());
				if (!line.endsWith(RETURN))
					process.getOutputStream().write(RETURN_DATA);
				process.getOutputStream().flush();
			}
		} catch (IOException e) {
			throw new RuntimeException(e);
		}
		return this;
	}
	
	private void drain(InputStream in) throws IOException {
		for (int $ = 0; $ != -1; $ = in.read()) ;
	}
	
	private Closeable pipe(InputStream in, OutputStream out) {
		final Future<?> task = executor.submit(() -> {
			final byte[] buffer = new byte[this.buffer];
			for (int length = 0; ; length = in.read(buffer)) {
				out.write(buffer, 0, length);
				out.flush();
			}
		});
		return () -> task.cancel(true);
	}