java分块上传 给一个例子
时间: 2024-01-16 14:02:14 浏览: 27
好的,以下是一个基于Java语言的分块上传示例:
```java
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayList;
import java.util.List;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.model.CompleteMultipartUploadRequest;
import com.aliyun.oss.model.InitiateMultipartUploadRequest;
import com.aliyun.oss.model.InitiateMultipartUploadResult;
import com.aliyun.oss.model.PartETag;
import com.aliyun.oss.model.UploadPartRequest;
import com.aliyun.oss.model.UploadPartResult;
public class OSSUploader {
// Endpoint以华东1(杭州)为例,其它Region请按实际情况填写。
private static String endpoint = "http://oss-cn-hangzhou.aliyuncs.com";
private static String accessKeyId = "<yourAccessKeyId>";
private static String accessKeySecret = "<yourAccessKeySecret>";
private static String bucketName = "<yourBucketName>";
private static String objectName = "<yourObjectName>";
private static String filePath = "<yourFilePath>";
private static OSS ossClient;
public static void main(String[] args) throws IOException, NoSuchAlgorithmException {
// 创建OSSClient实例。
ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);
// 初始化分块上传。
InitiateMultipartUploadRequest request = new InitiateMultipartUploadRequest(bucketName, objectName);
InitiateMultipartUploadResult result = ossClient.initiateMultipartUpload(request);
String uploadId = result.getUploadId();
System.out.println("UploadId: " + uploadId);
// 计算文件MD5值。
String md5 = calculateFileMd5(filePath);
// 分块上传文件。
File file = new File(filePath);
long fileLength = file.length();
long partSize = 1024 * 1024L; // 设置分块大小为1MB。
long partCount = fileLength / partSize + (fileLength % partSize == 0 ? 0 : 1);
List<PartETag> partETags = new ArrayList<PartETag>();
for (int i = 0; i < partCount; i++) {
long startPos = i * partSize;
long curPartSize = Math.min(partSize, fileLength - startPos);
FileInputStream fis = new FileInputStream(file);
fis.skip(startPos);
UploadPartRequest uploadPartRequest = new UploadPartRequest();
uploadPartRequest.setBucketName(bucketName);
uploadPartRequest.setKey(objectName);
uploadPartRequest.setUploadId(uploadId);
uploadPartRequest.setInputStream(fis);
uploadPartRequest.setPartSize(curPartSize);
uploadPartRequest.setPartNumber(i + 1);
UploadPartResult uploadPartResult = ossClient.uploadPart(uploadPartRequest);
fis.close();
partETags.add(uploadPartResult.getPartETag());
System.out.println("Part#" + (i + 1) + " upload success.");
}
// 完成分块上传。
CompleteMultipartUploadRequest completeMultipartUploadRequest = new CompleteMultipartUploadRequest(bucketName, objectName, uploadId, partETags);
ossClient.completeMultipartUpload(completeMultipartUploadRequest);
System.out.println("Upload success.");
// 关闭OSSClient。
ossClient.shutdown();
}
// 计算文件的MD5值。
private static String calculateFileMd5(String filePath) throws IOException, NoSuchAlgorithmException {
FileInputStream fis = new FileInputStream(filePath);
MessageDigest md5Digest = MessageDigest.getInstance("MD5");
byte[] buffer = new byte[1024];
int length = -1;
while ((length = fis.read(buffer)) != -1) {
md5Digest.update(buffer, 0, length);
}
fis.close();
byte[] md5Bytes = md5Digest.digest();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < md5Bytes.length; i++) {
sb.append(Integer.toHexString((md5Bytes[i] & 0xFF) | 0x100).substring(1, 3));
}
return sb.toString();
}
}
```
代码中使用了阿里云的Java SDK,在分块上传过程中,计算文件的MD5值,将文件分成若干个大小相等的块,并使用UploadPartRequest请求上传每个块,最后将所有块的编号和MD5值传递给CompleteMultipartUploadRequest请求,完成分块上传。