我认为你的期望和现实不符合（但是他们曾经有过））

I think your expectations and reality don't match (but when do they ever ;))

基本上，你认为文件写在哪里，文件实际写在哪里不等于（嗯，也许我应该写一个如果 statement;））

Basically, where you think the file is written and where the file is actually written are not equal (hmmm, perhaps I should write an if statement ;))

public class TestWriteFile {

    public static void main(String[] args) {
        BufferedWriter writer = null;
        try {
            //create a temporary file
            String timeLog = new SimpleDateFormat("yyyyMMdd_HHmmss").format(Calendar.getInstance().getTime());
            File logFile = new File(timeLog);

            // This will output the full path where the file will be written to...
            System.out.println(logFile.getCanonicalPath());

            writer = new BufferedWriter(new FileWriter(logFile));
            writer.write("Hello world!");
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                // Close the writer regardless of what happens...
                writer.close();
            } catch (Exception e) {
            }
        }
    }
}

另请注意，您的示例将覆盖任何现有文件。如果要将文本附加到文件中，您应该执行以下操作：

Also note that your example will overwrite any existing files. If you want to append the text to the file you should do the following instead:

writer = new BufferedWriter(new FileWriter(logFile, true));