本文介绍如何通过 Java SDK GetObject 接口设置图片转码参数,处理下载的图片。
从 2.6.0 版本开始,Java SDK GetObject 接口支持设置图片转码参数。
以下代码展示如何设置图片转码参数。
import com.volcengine.tos.TOSV2; import com.volcengine.tos.TOSV2ClientBuilder; import com.volcengine.tos.TosClientException; import com.volcengine.tos.TosServerException; import com.volcengine.tos.model.object.GetObjectV2Input; import com.volcengine.tos.model.object.GetObjectV2Output; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.util.Map; public class GetObjectWithPictureProcessExample { public static void main(String[] args) { String endpoint = "your endpoint"; String region = "your region"; String accessKey = System.getenv("TOS_ACCESS_KEY"); String secretKey = System.getenv("TOS_SECRET_KEY"); String bucketName = "bucket-example"; // 对象名 String objectKey = "example_dir/example_object.txt"; // 对象数据保存的本地文件路径,需保证不存在,否则会覆盖原有文件 String filePath = "example_dir/example_file.txt"; // 图片处理参数 String process = "the image process param"; TOSV2 tos = new TOSV2ClientBuilder().build(region, endpoint, accessKey, secretKey); GetObjectV2Input input = new GetObjectV2Input().setBucket(bucketName).setKey(objectKey) .setProcess(process); // 以下代码展示如何将数据下载到本地文件 File file = new File(filePath); if (file.getParentFile() != null && !file.getParentFile().exists()) { // 此处判断文件路径的父文件夹是否存在,不存在则创建父文件夹 // 如果父文件夹不存在且不创建,直接写入会报 FileNotFoundException file.getParentFile().mkdirs(); } try(GetObjectV2Output output = tos.getObject(input); FileOutputStream fos = new FileOutputStream(file)) { System.out.println("begin to read content in object to file."); if (output.getContent() != null) { byte[] buffer = new byte[4096]; int length; while ((length = output.getContent().read(buffer)) != -1) { fos.write(buffer, 0, length); } } fos.flush(); System.out.println("getObject succeed."); System.out.println("object's etag is " + output.getEtag()); System.out.println("object's lastModified is " + output.getLastModified()); System.out.println("object's crc64 value is " + output.getHashCrc64ecma()); System.out.println("object's storageClass is " + output.getStorageClass()); System.out.println("object's cacheControl is " + output.getCacheControl()); System.out.println("object's contentDisposition is " + output.getContentDisposition()); System.out.println("object's contentEncoding is " + output.getContentEncoding()); System.out.println("object's contentLanguage is " + output.getContentLanguage()); System.out.println("object's contentType is " + output.getContentType()); if (output.getCustomMetadata() != null) { System.out.println("object has custom meta data."); for (Map.Entry<String, String> entry : output.getCustomMetadata().entrySet()) { System.out.println("custom meta key: " + entry.getKey() + ", value: " + entry.getValue()); } } } catch (IOException e) { System.out.println("read data in object failed"); e.printStackTrace(); } catch (TosClientException e) { // 操作失败,捕获客户端异常,一般情况是请求参数错误,此时请求并未发送 System.out.println("getObject failed"); System.out.println("Message: " + e.getMessage()); if (e.getCause() != null) { e.getCause().printStackTrace(); } } catch (TosServerException e) { // 操作失败,捕获服务端异常,可以获取到从服务端返回的详细错误信息 System.out.println("getObject failed"); System.out.println("StatusCode: " + e.getStatusCode()); System.out.println("Code: " + e.getCode()); System.out.println("Message: " + e.getMessage()); System.out.println("RequestID: " + e.getRequestID()); } catch (Throwable t) { // 作为兜底捕获其他异常,一般不会执行到这里 System.out.println("getObject failed"); System.out.println("unexpected exception, message: " + t.getMessage()); } } }