JAVA解压缩文件——包含嵌套的压缩文件

Java中可以使用ZipInputStream和GZIPInputStream来解压缩压缩文件，其中ZipInputStream可以处理嵌套的压缩文件。

以下是一个用Java解压缩嵌套的压缩文件的示例代码：

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

public class UnzipExample {
    public static void unzip(File zipFile, File destination) throws IOException {
        byte[] buffer = new byte[1024];
        try (ZipInputStream zis = new ZipInputStream(new FileInputStream(zipFile))) {
            ZipEntry zipEntry = zis.getNextEntry();
            while (zipEntry != null) {
                File newFile = newFile(destination, zipEntry);
                if (zipEntry.isDirectory()) {
                    if (!newFile.isDirectory() && !newFile.mkdirs()) {
                        throw new IOException("Failed to create directory " + newFile);
                    }
                } else {
                    File parent = newFile.getParentFile();
                    if (!parent.isDirectory() && !parent.mkdirs()) {
                        throw new IOException("Failed to create directory " + parent);
                    }
                    try (FileOutputStream fos = new FileOutputStream(newFile)) {
                        int len;
                        while ((len = zis.read(buffer)) > 0) {
                            fos.write(buffer, 0, len);
                        }
                    }
                }
                zipEntry = zis.getNextEntry();
            }
        }
    }

    private static File newFile(File destinationDir, ZipEntry zipEntry) throws IOException {
        File destFile = new File(destinationDir, zipEntry.getName());
        String destDirPath = destinationDir.getCanonicalPath();
        String destFilePath = destFile.getCanonicalPath();
        if (!destFilePath.startsWith(destDirPath + File.separator)) {
            throw new IOException("Entry is outside of the target directory: " + zipEntry.getName());
        }
        return destFile;
    }

    public static void main(String[] args) throws IOException {
        File zipFile = new File("example.zip");
        File destination = new File("unzipped");
        unzip(zipFile, destination);
    }
}

该示例代码使用了try-with-resources语句来确保关闭流，它还包含了一个newFile()方法，该方法用于检查解压缩文件的目录是否在指定的目标目录中。