logger（java.util.logging）尽管在文件中打印输出，但突然停止将输出打印到控制台中

Question

I'm using java.util.logging to set up the logger and here's the code : fh = new FileHandler(file.getAbsolutePath()); logger.addHandler(fh); SimpleFormatter formatter = new SimpleFormatter(); fh.setFormatter(formatter); logger.setLevel(Level.ALL); fh = new FileHandler(file.getAbsolutePath()); logger.addHandler(fh); SimpleFormatter formatter = new SimpleFormatter(); fh.setFormatter(formatter); logger.setLevel(Level.ALL); The logger works fine with console and file .but after the below JSch code snippet `Channel channel = session.openChannel("exec");

    ((ChannelExec) channel).setCommand(cmd1);

    channel.setInputStream(null);
    ((ChannelExec) channel).setErrStream(System.err);

    logger.info("creating tar ,executing command :"+cmd1);

    channel.connect();

    while (true) {
        if (channel.isClosed()) {
            System.out.println( logger.getHandlers());
            // doesn't log afterwards
             logger.info("exit-status: " + channel.getExitStatus());
            if (channel.getExitStatus() == 0)
                logger.info("tar file with " + tarFileName
                        + "has been created successfully at " + path);
            break;
        }
        try {
            Thread.sleep(1000);
        } catch (Exception ee) {
        }
    }`

I guess the handler has changed when I'm executing the command.How can I reset the handler such that it starts printing into the console as well.

Answer 1

As described in JSch channel.disconnect prevent logs from printing

You have to change:

((ChannelExec) channel).setErrStream(System.err);

to

((ChannelExec) channel).setErrStream(System.err, true);

Otherwise System.err is closed when the channel is closed which will happen on exit. Closing System.err will prevent you from seeing output on the console.

Another option would be to wrap System.err in a stream that ignores calls to close.