// Create a COSClient instance, which is used to initiate requests later.
COSClient createCOSClient() {
    // Set user identity information.
    // To view and manage SECRETID and SECRETKEY, please log in to the Access Management Console at https://console.cloud.tencent.com/cam/capi
    String secretId = System.getenv("secretId"); // User's SecretId, it is recommended to use a sub-account key, following the principle of least privilege to reduce usage risks. For obtaining a sub-account key, please refer to https://cloud.tencent.com/document/product/598/37140
    String secretKey = System.getenv("secretKey"); // User's SecretKey, it is recommended to use a sub-account key, following the principle of least privilege to reduce usage risks. For obtaining a sub-account key, please refer to https://cloud.tencent.com/document/product/598/37140
    COSCredentials cred = new BasicCOSCredentials(secretId, secretKey);

    // ClientConfig contains the client settings for subsequent requests to COS:
    ClientConfig clientConfig = new ClientConfig();

    // Set the bucket region
    // For more information on COS regions, visit https://cloud.tencent.com/document/product/436/6224.
    clientConfig.setRegion(new Region("COS_REGION"));

    // Set the request protocol, either HTTP or HTTPS
    // For versions 5.6.53 and below, it is recommended to use the HTTPS protocol.
    // Version 5.6.54 and higher, HTTPS is used by default.
    clientConfig.setHttpProtocol(HttpProtocol.https);

    // The following settings are optional:

    // Set socket read timeout, default is 30 seconds
    clientConfig.setSocketTimeout(30*1000);
    // Set connection establishment timeout, default is 30 seconds
    clientConfig.setConnectionTimeout(30*1000);

    // Set the HTTP proxy, IP, and port if needed.
    clientConfig.setHttpProxyIp("httpProxyIp");
    clientConfig.setHttpProxyPort(80);

    // Create a COS client.
    return new COSClient(cred, clientConfig);
}


// Create a COSClient instance, which is used to initiate requests later.
COSClient createCOSClient() {
    // Here, the temporary key must have already been obtained.
    // For generating temporary keys, refer to https://cloud.tencent.com/document/product/436/14048#cos-sts-sdk
    String tmpSecretId = "TMPSECRETID";
    String tmpSecretKey = "TMPSECRETKEY";
    String sessionToken = "SESSIONTOKEN";

    COSCredentials cred = new BasicSessionCredentials(tmpSecretId, tmpSecretKey, sessionToken);

    // ClientConfig contains the client settings for subsequent requests to COS:
    ClientConfig clientConfig = new ClientConfig();

    // Set the bucket region
    // For COS_REGION, please refer to https://cloud.tencent.com/document/product/436/6224
    clientConfig.setRegion(new Region("COS_REGION"));

    // Set the request protocol, either HTTP or HTTPS
    // For versions 5.6.53 and below, it is recommended to use the HTTPS protocol.
    // Version 5.6.54 and higher, HTTPS is used by default.
    clientConfig.setHttpProtocol(HttpProtocol.https);

    // The following settings are optional:

    // Set socket read timeout, default is 30 seconds
    clientConfig.setSocketTimeout(30*1000);
    // Set connection establishment timeout, default is 30 seconds
    clientConfig.setConnectionTimeout(30*1000);

    // Set the HTTP proxy, IP, and port if needed.
    clientConfig.setHttpProxyIp("httpProxyIp");
    clientConfig.setHttpProxyPort(80);

    // Create a COS client.
    return new COSClient(cred, clientConfig);
}

public CopyObjectResult copyObject(CopyObjectRequest copyObjectRequest)
            throws CosClientException, CosServiceException

// Before using the COS API, ensure that the process contains a COSClient instance. If such an instance does not exist, create one.
// For the detailed code, see "Simple Upload -> Creating a COSClient instance" on the current page.
COSClient cosClient = createCOSClient();

// Region where the bucket resides
// For more information on COS regions, visit https://cloud.tencent.com/document/product/436/6224.
Region region = new Region("ap-beijing");
// Enter the bucket name in the format of BucketName-APPID.
String bucketName = "examplebucket-1250000000";
// The Object Key is the unique identifier for an object within a bucket. For more information, please refer to [Object Key](https://cloud.tencent.com/document/product/436/13324).
String key = "exampleobject";

// Get the current object metadata.
ObjectMetadata objectMetadata = cosClient.getObjectMetadata(bucketName, key);
// Replaced must be set if you modify object metadata.
objectMetadata.setHeader("x-cos-metadata-directive", "Replaced");

// Set the new object metadata.
// Note: For Content-Disposition, custom metadata, or other header fields with Chinese characters, call UrlEncoderUtils.encode(String) for encoding before setting to avoid signature issues. 
objectMetadata.setHeader("x-cos-storage-class", "STANDARD_IA");
objectMetadata.setContentType("text/plain");

CopyObjectRequest copyObjectRequest = new CopyObjectRequest(region, bucketName, key, bucketName, key);
copyObjectRequest.setNewObjectMetadata(objectMetadata);

try {
    CopyObjectResult copyObjectResult = cosClient.copyObject(copyObjectRequest);
    System.out.print(copyObjectResult.getRequestId());
} catch (CosServiceException e) {
    e.printStackTrace();
} catch (CosClientException e) {
    e.printStackTrace();
}

// After confirming that the current process no longer uses the cosClient instance, close it.
cosClient.shutdown();