这是一个简单的四步流程，其中三步由Stackoverflow Questions解决：

1. Read each line and turn them into Java String
   1.将每个Java字符串存储在一个Array中（不认为您需要引用这个字符串）。
2. Sort your Array
3. Write out each Java String in your array

以下是使用“集合”排序的示例：

public static void sortFile() throws IOException
{     
    FileReader fileReader = new FileReader("C:\\words.txt");
    BufferedReader bufferedReader = new BufferedReader(fileReader);
    List<String> lines = new ArrayList<String>();
    String line = null;
    while ((line = bufferedReader.readLine()) != null) {
        lines.add(line);
    }
    bufferedReader.close();

    Collections.sort(lines, Collator.getInstance());

    FileWriter writer = new FileWriter("C:\\wordsnew.txt"); 
    for(String str: lines) {
      writer.write(str + "\r\n");
    }
    writer.close();
}

您也可以像这样使用自己的归类：

Locale lithuanian = new Locale("lt_LT");
Collator lithuanianCollator = Collator.getInstance(lithuanian);

import java.io.*;
import java.util.*;

public class example
{
    TreeSet<String> tree=new TreeSet<String>();
    public static void main(String args[])
    {
        new example().go();
    }
    public void go()

    {
        getlist();
        System.out.println(tree);

    }
     void getlist()
    {
        try
        {
            File myfile= new File("C:/Users/Rajat/Desktop/me.txt");
            BufferedReader reader=new BufferedReader(new FileReader(myfile));
            String line=null;
            while((line=reader.readLine())!=null){
                addnames(line);

            }
        reader.close();
        }

        catch(Exception ex)
        {
            ex.printStackTrace();
        }

    }
    void addnames(String a)
    {
           tree.add(a);
           for(int i=1;i<=a.length();i++)
           {

           }
    }
}

public List<String> readFile(String filePath) throws FileNotFoundException {
    List<String> txtLines = new ArrayList<>();
    try {
        BufferedReader reader = new BufferedReader(new FileReader(filePath));
        String line;
        while (!((line = reader.readLine()) == null)) {
            txtLines.add(line);
        }
    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return txtLines.stream().sorted().collect(Collectors.toList());
}