Запись в существующий файл

import org.jsoup.*;
import org.jsoup.nodes.*;
import org.jsoup.select.*;
 
import java.io.*;
import java.text.*;
import java.util.*;
 
public class Market {
    public static void main(String[] args) throws IOException {
 
        Document doc = Jsoup
                .connect("")
                .userAgent("Safari").get();
        
    
        File flt = new File("document.doc");
        FileWriter wrt = new FileWriter(flt);
 
        // DateFormat dateF = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");
        // Calendar cal = Calendar.getInstance();
        // String time = dateF.format(cal.getTime());
        // wrt.append(time);
 
        String title = doc.title();
        wrt.append(title);
        ;
 
        Elements links1 = doc.getElementsByTag("a");
        for (Element link : links1) {
            System.out.println(link.text());
            wrt.append(link.text());
            ;
        }
 
        Elements links2 = doc.getElementsByTag("b");
        for (Element link : links2) {
            System.out.println(link.text());
            wrt.append(link.text());
            ;
        }
 
        wrt.flush();
        System.out.println("Output is generated in a file document.doc");
        wrt.close();
 
    }
}

 File flt = new File("D:\\document.txt");
            wrt = new FileWriter(flt, true);

/*
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 * and open the template in the editor.
 */
package javaapplication3;
import java.io.*;
import java.text.*;
import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;
/**
 *
 * @author Peter
 */
public class JavaApplication3
{
 
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args)
    {
        FileWriter wrt = null;
        try
        {
            File flt = new File("D:\\document.txt");
            wrt = new FileWriter(flt, true);
            DateFormat dateF = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");
            Calendar cal = Calendar.getInstance();
            String time = dateF.format(cal.getTime());
            wrt.append(time);
        } catch (IOException ex)
        {
            LOG.log(Level.SEVERE, null, ex);
        } finally
        {
            try
            {
                wrt.close();
            } catch (IOException ex)
            {
                   LOG.log(Level.SEVERE, null, ex);
            }
        }
    }
    private static final Logger LOG = Logger.getLogger(JavaApplication3.class.getName());
}

Exception in thread "main" java.lang.ExceptionInInitializerError
    at java.nio.file.FileSystems.getDefault(FileSystems.java:176)
    at sun.util.calendar.ZoneInfoFile$1.run(ZoneInfoFile.java:483)
    at sun.util.calendar.ZoneInfoFile$1.run(ZoneInfoFile.java:478)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.util.calendar.ZoneInfoFile.<clinit>(ZoneInfoFile.java:477)
    at sun.util.calendar.ZoneInfo.getTimeZone(ZoneInfo.java:663)
    at java.util.TimeZone.getTimeZone(TimeZone.java:566)
    at java.util.TimeZone.setDefaultZone(TimeZone.java:663)
    at java.util.TimeZone.getDefaultRef(TimeZone.java:630)
    at java.util.TimeZone.getDefault(TimeZone.java:617)
    at java.text.SimpleDateFormat.initializeCalendar(SimpleDateFormat.java:682)
    at java.text.SimpleDateFormat.<init>(SimpleDateFormat.java:581)
    at java.text.SimpleDateFormat.<init>(SimpleDateFormat.java:560)
    at Market.main(Market.java:21)
Caused by: java.lang.RuntimeException: default directory must be absolute
    at sun.nio.fs.UnixFileSystem.<init>(UnixFileSystem.java:54)
    at sun.nio.fs.BsdFileSystem.<init>(BsdFileSystem.java:41)
    at sun.nio.fs.MacOSXFileSystem.<init>(MacOSXFileSystem.java:44)
    at sun.nio.fs.MacOSXFileSystemProvider.newFileSystem(MacOSXFileSystemProvider.java:43)
    at sun.nio.fs.MacOSXFileSystemProvider.newFileSystem(MacOSXFileSystemProvider.java:36)
    at sun.nio.fs.UnixFileSystemProvider.<init>(UnixFileSystemProvider.java:56)
    at sun.nio.fs.BsdFileSystemProvider.<init>(BsdFileSystemProvider.java:38)
    at sun.nio.fs.MacOSXFileSystemProvider.<init>(MacOSXFileSystemProvider.java:38)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
    at java.lang.Class.newInstance(Class.java:374)
    at sun.nio.fs.DefaultFileSystemProvider$1.run(DefaultFileSystemProvider.java:52)
    at sun.nio.fs.DefaultFileSystemProvider$1.run(DefaultFileSystemProvider.java:43)
    at java.security.AccessController.doPrivileged(Native Method)
    at sun.nio.fs.DefaultFileSystemProvider.createProvider(DefaultFileSystemProvider.java:42)
    at sun.nio.fs.DefaultFileSystemProvider.create(DefaultFileSystemProvider.java:72)
    at java.nio.file.FileSystems$DefaultFileSystemHolder.getDefaultProvider(FileSystems.java:108)
    at java.nio.file.FileSystems$DefaultFileSystemHolder.access$000(FileSystems.java:89)
    at java.nio.file.FileSystems$DefaultFileSystemHolder$1.run(FileSystems.java:98)
    at java.nio.file.FileSystems$DefaultFileSystemHolder$1.run(FileSystems.java:96)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.nio.file.FileSystems$DefaultFileSystemHolder.defaultFileSystem(FileSystems.java:95)
    at java.nio.file.FileSystems$DefaultFileSystemHolder.<clinit>(FileSystems.java:90)
    ... 14 more

DateFormat dateF = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");

  SimpleDateFormat dateF = new SimpleDateFormat("dd/MM/yyyy HH:mm:ss");

            Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("UTC"));