获取图片信息功能可以获取到图片的基本信息,包括图片的长、宽、大小和格式。如果图片包含 Exif 信息,将按照 JSON 格式返回内容。本文介绍如何通过 TOS Java SDK 获取图片信息。
以下代码展示如何获取图片信息。
import com.fasterxml.jackson.core.JacksonException; import com.fasterxml.jackson.databind.JsonNode; import com.volcengine.tos.TOSV2; import com.volcengine.tos.TOSV2ClientBuilder; import com.volcengine.tos.TosClientException; import com.volcengine.tos.TosServerException; import com.volcengine.tos.internal.util.TosUtils; import com.volcengine.tos.model.object.GetObjectV2Input; import com.volcengine.tos.model.object.GetObjectV2Output; import java.io.ByteArrayOutputStream; import java.io.IOException; public class ImageInfoExample { 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"; // 需要确保对象已存在 String objectKey = "image.png"; String style = "image/info"; // 获取图片信息 TOSV2 tos = new TOSV2ClientBuilder().build(region, endpoint, accessKey, secretKey); try { GetObjectV2Input input = new GetObjectV2Input().setBucket(bucketName).setKey(objectKey).setProcess(style); try (ByteArrayOutputStream stream = new ByteArrayOutputStream(); GetObjectV2Output output = tos.getObject(input)) { byte[] buffer = new byte[1024]; int length; while ((length = output.getContent().read(buffer)) != -1) { stream.write(buffer, 0, length); } String respBody = stream.toString("UTF-8"); System.out.println("Get image info succeed, image info is " + respBody); JsonNode jsonNode = TosUtils.getJsonMapper().readTree(respBody); String height = jsonNode.get("ImageHeight").get("value").asText(); String width = jsonNode.get("ImageWidth").get("value").asText(); String fileSize = jsonNode.get("FileSize").get("value").asText(); String format = jsonNode.get("Format").get("value").asText(); System.out.println("Image info height:" + height + ", width:" + width + ", size:" + fileSize + ", format:" + format); } catch (JacksonException e) { System.out.println("parse response data failed"); e.printStackTrace(); } catch (IOException e) { System.out.println("read response data 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("get image info 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("get image info 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("get image info failed"); System.out.println("unexpected exception, message: " + t.getMessage()); } } }
关于获取图片信息的详细介绍,请参见获取信息。