文件夹监视器Java代码打印报告两次

使用这个站点的一些答案，我用Java创建了一个小的文件夹监视器应用程序。它应该检查对特定文件夹的更改，并将这些更改输出到文本文件。不幸的是，每次更改都会打印两次报告。问题是我不知道报告的第一行是从哪里来的。请帮助我理解我做错了什么

请在下面查找代码。我删除了部分代码，因为它不影响问答

import java.io.File;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.commons.io.monitor.FileAlterationListener;
import org.apache.commons.io.monitor.FileAlterationListenerAdaptor;
import org.apache.commons.io.monitor.FileAlterationMonitor;
import org.apache.commons.io.monitor.FileAlterationObserver;

public class FolderMonitor {

    public FolderMonitor() {}

    //path to a folder you are monitoring
    public static final String FOLDER = "D:\\WatchedDir";

    public static void main(String[] args) throws Exception 
    {
        System.out.println("monitoring started");
        // The monitor will perform polling on the folder every 5 seconds
        final long pollingInterval = 6 * 1000;

        // Let's get a directory as a File object and sort all its files.
        File folderToMonitor = new File(FOLDER);
        File outputFile = new File("H:\\Dir_changes.txt");          

        if (!folderToMonitor.exists()) 
        {
            // Test to see if monitored folder exists
            throw new RuntimeException("Directory not found: " + FOLDER);
        }           

        FileAlterationObserver observer = new FileAlterationObserver(folderToMonitor);
        FileAlterationMonitor monitor = new FileAlterationMonitor(pollingInterval);
        FileAlterationListener listener = new FileAlterationListenerAdaptor() 
        {           
            // Is triggered when a file in the monitored folder is modified from 
            @Override
            public void onFileChange(File file) 
            {
                // "file" is the reference to the newly created file                
                try {writeToFile(outputFile, convertLongToDate(outputFile.lastModified()), ("File modified: "+ file.getCanonicalPath()));}               
                    catch (IOException e) {e.printStackTrace();} 
            }           
        };

        observer.addListener(listener);
        monitor.addObserver(observer);
        monitor.start();
    }

    private static void writeToFile(File filePath, String timeStamp, String caughtChange) throws IOException
    {
        FileWriter fileWriter = new FileWriter(filePath,true);

        BufferedWriter bufferFileWriter  = new BufferedWriter(fileWriter);

        fileWriter.append("\r" + timeStamp + " - " + caughtChange + "\r");

        bufferFileWriter.close();     
    }

    private static String convertLongToDate(long input)
    {
        Date date = new Date(input);
        Calendar cal = new GregorianCalendar();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MMM/dd hh:mm:ss z");
        sdf.setCalendar(cal);
        cal.setTime(date);
        return sdf.format(date);
    }
}

输出如下所示：

1454622374878文件已修改：D:\WatchedDir\second\inside3.txt 2016/Feb/04 04:46:25美国东部时间-文件修改：D:\WatchedDir\second\inside3.txt

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我不知道突出显示（粗体）的部分是从哪里来的，以及如何去掉它。请帮忙

我运行了与您发布的相同的代码，在.txt文件中没有看到额外的输出。您可以尝试将输出定向到一个新文件，看看它是否有任何不同，因为Eclipse正在执行我已经从类中删除并保存更改的代码

在我重新启动Eclipse并再次执行代码之后，一切都正常运行（令人惊讶）

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我考虑过删除这篇文章，但我决定离开它，以防有人会寻找这样一段代码。我将由版主决定是否删除此问题。

感谢您抽出时间检查！