在google云中使用blob获取文件大小

import com.google.cloud.storage.Blob;
import com.google.cloud.storage.BlobId;
import com.google.cloud.storage.Storage;
import com.google.cloud.storage.StorageOptions;

public class BlobFileSizeExample {
    public static void main(String[] args) {
        // 设置Google云存储的项目ID
        String projectId = "your-project-id";
        
        // 创建Google云存储的客户端
        Storage storage = StorageOptions.newBuilder().setProjectId(projectId).build().getService();
        
        // 设置要获取文件大小的Blob对象的信息
        String bucketName = "your-bucket-name";
        String blobName = "your-blob-name";
        
        // 创建BlobId对象
        BlobId blobId = BlobId.of(bucketName, blobName);
        
        // 获取Blob对象
        Blob blob = storage.get(blobId);
        
        // 获取文件大小（以字节数表示）
        long fileSize = blob.getSize();
        
        // 将字节数转换为适当的单位
        String fileSizeString = humanReadableFileSize(fileSize);
        
        System.out.println("文件大小：" + fileSizeString);
    }
    
    // 将字节数转换为适当的单位（KB、MB或GB）
    private static String humanReadableFileSize(long size) {
        if (size <= 0) {
            return "0";
        }
        
        final String[] units = new String[] { "B", "KB", "MB", "GB", "TB" };
        int digitGroups = (int) (Math.log10(size) / Math.log10(1024));
        
        return String.format("%.2f %s", size / Math.pow(1024, digitGroups), units[digitGroups]);
    }
}