Question

我在以下网址浏览过StreamGobbler

我了解其实施的用法和原因。但是，所涵盖的场景只是那些可能存在来自命令/处理错误的输出的场景。

我没有找到使用StreamGobbler处理输入的任何场景。例如，在mailx中，我必须指定电子邮件的正文，我已按以下格式指定

Process proc = Runtime.getRuntime().exec(cmd);
OutputStreamWriter osw = new OutputStreamWriter(proc.getOutputStream());
osw.write(mailBody);
osw.close();

如何通过StreamGobbler处理，或者不需要通过它处理。

Answer 1

理想情况下，如果您已经期望StreamGobbler上的某些内容，则可以在错误流上使用InputStream（在单独的帖子中），以查看process.waitFor()何时返回非-zero值以找出错误消息。如果您对InputStream不感兴趣，那么一旦完成对命令的输入，就可以直接在代码中读取ErrorStream。

Process proc = Runtime.getRuntime().exec(cmd)
// Start a stream gobbler to read the error stream.
StreamGobbler errorGobbler = new StreamGobbler(proc.getErrorStream());
errorGobbler.start();

OutputStreamWriter osw = new OutputStreamWriter(proc.getOutputStream())
osw.write(mailBody)
osw.close();

int exitStatus = proc.waitFor();
if (0 != exitStatus) {
    /*
     * If you had not used a StreamGobbler to read the errorStream, you wouldn't have
     * had a chance to know what went wrong with this command execution.
     */
    LOG.warn("Error while sending email: " + errorGobbler.getContent());
}

使用StreamGobbler处理输入

1 个答案: