防止从ZipOutPutStream中删除重复项

import java.io.*;
import java.util.HashSet;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

public class ZipUtils {
    public static void createZipFile(String zipFilePath, String[] files) {
        try {
            FileOutputStream fos = new FileOutputStream(zipFilePath);
            ZipOutputStream zos = new ZipOutputStream(fos);
            HashSet<String> addedFiles = new HashSet<>();

            for (String filePath : files) {
                File file = new File(filePath);
                if (file.exists()) {
                    String fileName = file.getName();
                    if (!addedFiles.contains(fileName)) {
                        addedFiles.add(fileName);
                        addToZip(file, fileName, zos);
                    }
                }
            }

            zos.close();
            fos.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private static void addToZip(File file, String fileName, ZipOutputStream zos) throws IOException {
        FileInputStream fis = new FileInputStream(file);
        ZipEntry zipEntry = new ZipEntry(fileName);
        zos.putNextEntry(zipEntry);

        byte[] buffer = new byte[1024];
        int length;
        while ((length = fis.read(buffer)) > 0) {
            zos.write(buffer, 0, length);
        }

        zos.closeEntry();
        fis.close();
    }

    public static void main(String[] args) {
        String[] files = {"file1.txt", "file2.txt", "file3.txt", "file1.txt"};
        createZipFile("output.zip", files);
    }
}