Java提供了多種方法來壓縮文件夾。下面將介紹兩種常用的方法：使用ZipOutputStream和使用Apache Commons Compress庫。

1. 使用ZipOutputStream：

import java.io.*;

import java.util.zip.*;

public class ZipFolderExample {

public static void main(String[] args) {

String sourceFolder = "path/to/source/folder";

String zipFile = "path/to/destination/zipfile.zip";

try {

FileOutputStream fos = new FileOutputStream(zipFile);

ZipOutputStream zos = new ZipOutputStream(fos);

zipFolder(sourceFolder, zos);

zos.close();

fos.close();

System.out.println("Folder successfully compressed to " + zipFile);

} catch (IOException e) {

e.printStackTrace();

}

}

private static void zipFolder(String sourceFolder, ZipOutputStream zos) throws IOException {

File folder = new File(sourceFolder);

if (!folder.exists()) {

throw new FileNotFoundException("Folder not found: " + sourceFolder);

}

File[] files = folder.listFiles();

if (files != null) {

for (File file : files) {

if (file.isDirectory()) {

zipFolder(file.getAbsolutePath(), zos);

} else {

byte[] buffer = new byte[1024];

FileInputStream fis = new FileInputStream(file);

zos.putNextEntry(new ZipEntry(file.getName()));

int length;

while ((length = fis.read(buffer)) > 0) {

zos.write(buffer, 0, length);

}

zos.closeEntry();

fis.close();

}

}

}

}

2. 使用Apache Commons Compress庫：

import org.apache.commons.compress.archivers.zip.*;

import org.apache.commons.compress.utils.IOUtils;

import java.io.*;

import java.nio.file.*;

public class ZipFolderExample {

public static void main(String[] args) {

String sourceFolder = "path/to/source/folder";

String zipFile = "path/to/destination/zipfile.zip";

try {

FileOutputStream fos = new FileOutputStream(zipFile);

ZipArchiveOutputStream zos = new ZipArchiveOutputStream(fos);

zipFolder(sourceFolder, zos);

zos.close();

fos.close();

System.out.println("Folder successfully compressed to " + zipFile);

} catch (IOException e) {

e.printStackTrace();

}

}

private static void zipFolder(String sourceFolder, ZipArchiveOutputStream zos) throws IOException {

File folder = new File(sourceFolder);

if (!folder.exists()) {

throw new FileNotFoundException("Folder not found: " + sourceFolder);

}

File[] files = folder.listFiles();

if (files != null) {

for (File file : files) {

if (file.isDirectory()) {

zipFolder(file.getAbsolutePath(), zos);

} else {

ZipArchiveEntry entry = new ZipArchiveEntry(file, file.getName());

zos.putArchiveEntry(entry);

FileInputStream fis = new FileInputStream(file);

IOUtils.copy(fis, zos);

zos.closeArchiveEntry();

fis.close();

}

}

}

}

以上兩種方法都可以將指定的文件夾及其子文件夾壓縮為一個ZIP文件。你可以根據需要選擇其中一種方法來使用。