Use Java SDK for vector search - Object Storage Service - Alibaba Cloud Documentation Center

OSS vector search lets you quickly find object files from a large collection of objects based on semantic content, OSS metadata, multimedia metadata, object ETags, tags, and custom metadata. This feature improves retrieval efficiency.

Notes

Only Java software development kit (SDK) versions 3.18.2 and later support the vector search feature.
The vector search feature is supported for buckets in the following regions: China (Qingdao), China (Beijing), China (Zhangjiakou), China (Hangzhou), China (Shanghai), China (Shenzhen), China (Guangzhou), China (Chengdu), China (Hong Kong), Singapore, Indonesia (Jakarta), Germany (Frankfurt), US (Virginia), and US (Silicon Valley).
In this topic, the public endpoint of the China (Hangzhou) region is used. To access OSS from other Alibaba Cloud services in the same region, use an internal endpoint. For details about supported regions and endpoints, see OSS regions and endpoints.
In this topic, access credentials are obtained from environment variables. For more information about how to configure access credentials, see Configure access credentials.
In this topic, an OSSClient instance is created by using an OSS endpoint. If you want to create an OSSClient instance by using custom domain names or Security Token Service (STS), see Configuration examples for common scenarios.
By default, an Alibaba Cloud account has the permissions required to perform data indexing operations. If you want to use a Resource Access Management (RAM) user or STS to perform data indexing operations, you must have the following permissions:
- To enable the metadata management feature, you must have the oss:OpenMetaQuery permission.
- To retrieve information about a metadata index, you must have the oss:GetMetaQueryStatus permission.
- To query for objects that meet specified conditions, you must have the oss:DoMetaQuery permission.
- To disable the metadata management feature, you must have the oss:CloseMetaQuery permission.

Sample code

Enable the vector search feature

The following code provides an example of how to enable the vector search feature for a specified bucket.

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.MetaQueryMode;

public class OpenMetaQuery {
    public static void main(String[] args) throws com.aliyuncs.exceptions.ClientException {
        // The endpoint is set to China (Hangzhou) in this example. Replace it with the actual endpoint.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Specify the bucket name, for example, examplebucket.
        String bucketName = "examplebucket";
        // Obtain access credentials from environment variables. Before you run this sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are set.
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the region where the bucket is located. This example uses cn-hangzhou, which indicates the China (Hangzhou) region.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // When the OSSClient instance is no longer needed, call the shutdown method to release its resources.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            // Enable the vector search feature.
            ossClient.openMetaQuery(bucketName, MetaQueryMode.SEMANTIC);
        } catch (OSSException oe) {
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Error Message: " + ce.getMessage());
        } finally {
            // Shut down the OSSClient.
            if(ossClient != null){
                ossClient.shutdown();
            }
        }
    }
}

Get information about the metadata index

The following code provides an example of how to retrieve information about the metadata index of a specified bucket.

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.GetMetaQueryStatusResult;

public class GetMetaQueryStatus {
    public static void main(String[] args) throws com.aliyuncs.exceptions.ClientException {
        // The endpoint is set to China (Hangzhou) in this example. Replace it with the actual endpoint.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Specify the bucket name, for example, examplebucket.
        String bucketName = "examplebucket";
        // Obtain access credentials from environment variables. Before you run this sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are set.
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the region where the bucket is located. This example uses cn-hangzhou, which indicates the China (Hangzhou) region.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // When the OSSClient instance is no longer needed, call the shutdown method to release its resources.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            // Get information about the metadata index of the specified bucket.
            GetMetaQueryStatusResult getResult = ossClient.getMetaQueryStatus(bucketName);
             // Get the current retrieval pattern.
            System.out.println(getResult.getMetaQueryMode().toString());
            // Get the current scan type.
            System.out.println(getResult.getPhase());
            // Get the status of the metadata index.
            System.out.println(getResult.getState());
            // Get the time when the metadata index was created.
            System.out.println(getResult.getCreateTime());
            // Get the time when the metadata index was last updated.
            System.out.println(getResult.getUpdateTime());
        } catch (OSSException oe) {
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Error Message: " + ce.getMessage());
        } finally {
            // Shut down the OSSClient.
            if(ossClient != null){
                ossClient.shutdown();
            }
        }
    }
}

Query for objects that meet specified conditions

The following code provides an example of how to use the vector search feature to query for objects that match specified semantic content.

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.CredentialsProviderFactory;
import com.aliyun.oss.common.auth.EnvironmentVariableCredentialsProvider;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.*;
import java.util.ArrayList;
import java.util.List;

public class DoMetaQuery {
    public static void main(String[] args) throws Exception {
        // The endpoint is set to China (Hangzhou) in this example. Replace it with the actual endpoint.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Specify the bucket name, for example, examplebucket.
        String bucketName = "examplebucket";
        // Obtain access credentials from environment variables. Before you run this sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are set.
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the region where the bucket is located. This example uses cn-hangzhou, which indicates the China (Hangzhou) region.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // When the OSSClient instance is no longer needed, call the shutdown method to release its resources.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            int maxResults = 20;
            List<String> mediaTypes = new ArrayList<String>();
            mediaTypes.add("image");
            String query = "Snow";
            String simpleQuery = "{\"Operation\":\"gt\", \"Field\": \"Size\", \"Value\": \"30\"}";
            String sort = "Size";
            DoMetaQueryRequest doMetaQueryRequest = new DoMetaQueryRequest(bucketName, maxResults, query, sort, MetaQueryMode.SEMANTIC, mediaTypes, simpleQuery);
            DoMetaQueryResult doMetaQueryResult = ossClient.doMetaQuery(doMetaQueryRequest);
        } catch (OSSException oe) {
            System.out.println("Error Message: " + oe.getErrorMessage());
            System.out.println("Error Code:       " + oe.getErrorCode());
            System.out.println("Request ID:      " + oe.getRequestId());
            System.out.println("Host ID:           " + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Error Message: " + ce.getMessage());
        } finally {
            if(ossClient != null){
                ossClient.shutdown();
            }
        }
    }
}

Disable the vector search feature

The following code provides an example of how to disable the vector search feature for a specified bucket.

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;

public class CloseMetaQuery {
    public static void main(String[] args) throws Exception {
        // The endpoint is set to China (Hangzhou) in this example. Replace it with the actual endpoint.
        String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
        // Specify the bucket name, for example, examplebucket.
        String bucketName = "examplebucket";
        // Obtain access credentials from environment variables. Before you run this sample code, make sure that the OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET environment variables are set.
        EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
        // Specify the region where the bucket is located. This example uses cn-hangzhou, which indicates the China (Hangzhou) region.
        String region = "cn-hangzhou";

        // Create an OSSClient instance.
        // When the OSSClient instance is no longer needed, call the shutdown method to release its resources.
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(credentialsProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            // Disable the vector search feature for the bucket.
            ossClient.closeMetaQuery(bucketName);
        } catch (OSSException oe) {
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Error Message: " + ce.getMessage());
        } finally {
            // Shut down the OSSClient.
            if(ossClient != null){
                ossClient.shutdown();
            }
        }
    }
}

References

For more information about the API operation to enable the metadata management feature, see OpenMetaQuery.
For more information about the API operation to retrieve information about a metadata index, see GetMetaQueryStatus.
For more information about the API operation to query for objects that meet specified conditions, see DoMetaQuery.
For more information about the API operation to disable the metadata management feature, see CloseMetaQuery.