[TDR Generic Table][Java SDK] Batch Get Multiple Records

1. Interface Description

Get multiple records in batches from the specified table.

For more details, see Batch Operation Interface Description.

2. Version Requirements

This interface is provided in all versions without special requirements.

3. Preparations

Refer to Preparation document to complete the preparation before using this interface and create the following TDR Generic table.

Get the following information after the preparation. These details will be used by the SDK:

1. Directory server address list
2. App ID
3. App access password
4. Game zone ID
5. Table name

4. Example Code

Basic execution process of example code:

1. Create a client;
2. Create a request;
3. Send a request;
4. Process the response;
5. Destroy the client.

4.1 Example Code for Synchronous Call

import com.tencent.tcaplus.client.Client;
import com.tencent.tcaplus.client.ClientFactory;
import com.tencent.tcaplus.client.Record;
import com.tencent.tcaplus.client.Request;
import com.tencent.tcaplus.client.Response;
import com.tencent.tdr.tcaplus_protocol_cs.TcaplusProtocolCsConstants;

import java.util.ArrayList;
import java.util.List;

public class Example {

    public static void main(String[] arguments) {
        // 1. Prepare the environment information
        // 1.1. Directory server address list
        List<String> dirList = new ArrayList<String>();
        dirList.add("tcp://x.x.x.x:9999");
        dirList.add("tcp://y.y.y.y:9999");
        // 1.2. App ID
        int appId = 1;
        // 1.3. App password
        String appPassword = "****************";
        // 1.4. Table group ID
        int tableGroupId = 1;
        // 1.5. Table name
        String tableName = "test";

        // 2. Create a client
        Client client = ClientFactory.createClient(appId, tableGroupId, appPassword, dirList);
        try {
            // 3. Construct a request to get data in batches
            // 3.1. Get the request object. In order to improve the SDK's performance, the Request object is reused
            Request request = client.acquireRequest();
            // 3.2. Set the request type and target table name
            request.setCmd(TcaplusProtocolCsConstants.TCAPLUS_CMD_BATCH_GET_REQ);
            request.setTableName(tableName);
            // 3.3. Get 100 pieces of data in batches and set the value of each Key field
            for (int index = 0; index < 100; index++) {
                Record record = request.addRecord();
                record.setKeyInt("gameid", 1);
                record.setKeyInt("itemid", index);
                record.setKeyString("name", "test");
            }
            // 3.4. Add the Value field to be read
            request.addFieldName("typeid");
            request.addFieldName("Data");
            request.addFieldName("uname");

            // 4. Send a request and get the result
            Response response = client.poll(request);

            // 5. Process the result
            if (response.getResult() == 0) {
                // Data batch-reading successful
                Record result;
                while ((result = response.fetchRecord()) != null) {
                    // TODO: add the code to process the result of data batch-reading successful here
                }
            } else {
                // Data batch-reading failure
                // TODO: add the code to process the result of data batch-reading failure here
            }
        } finally {
            // 6. Destroy the client object
            ClientFactory.destroyClient(client);
        }
    }

}

4.2 Example Code for Asynchronous Call

import com.tencent.tcaplus.client.Client;
import com.tencent.tcaplus.client.ClientFactory;
import com.tencent.tcaplus.client.Record;
import com.tencent.tcaplus.client.Request;
import com.tencent.tcaplus.client.Response;
import com.tencent.tdr.tcaplus_protocol_cs.TcaplusProtocolCsConstants;

import java.util.ArrayList;
import java.util.List;

public class Example {

    public static void main(String[] arguments) {
        // 1. Prepare the environment information
        // 1.1. Directory server address list
        List<String> dirList = new ArrayList<String>();
        dirList.add("tcp://x.x.x.x:9999");
        dirList.add("tcp://y.y.y.y:9999");
        // 1.2. App ID
        int appId = 1;
        // 1.3. App password
        String appPassword = "****************";
        // 1.4. Table group ID
        int tableGroupId = 1;
        // 1.5. Table name
        String tableName = "test";

        // 2. Create a client
        Client client = ClientFactory.createClient(appId, tableGroupId, appPassword, dirList);
        try {
            // 3. Construct a request to get data in batches
            // 3.1. Get the request object. In order to improve the SDK's performance, the Request object is reused
            Request request = client.acquireRequest();
            // 3.2. Set the request type and target table name
            request.setCmd(TcaplusProtocolCsConstants.TCAPLUS_CMD_BATCH_GET_REQ);
            request.setTableName(tableName);
            // 3.3. Get 100 pieces of data in batches and set the value of each Key field
            for (int index = 0; index < 100; index++) {
                Record record = request.addRecord();
                record.setKeyInt("gameid", 1);
                record.setKeyInt("itemid", index);
                record.setKeyString("name", "test");
            }
            // 3.4. Add the Value field to be read
            request.addFieldName("typeid");
            request.addFieldName("Data");
            request.addFieldName("uname");

            CountDownLatch latch = new CountDownLatch(1);

            // 4. Send the request asynchronously and specify the processor that returns the response. The post method will return the result immediately
            client.post(request, new Future() {

                @Override
                public void onResponse(Response response) {
                    // 5. Process the response
                    if (response.getResult() == 0) {
                        // Data getting success
                        // TODO: add the subsequent processing code of successful data getting here
                    } else {
                        // Data getting failure
                        // TODO: add the subsequent processing code of failed data getting here
                    }
                }

            });

            latch.await();
        } finally {
            // 6. Destroy the client object
            ClientFactory.destroyClient(client);
        }
    }

}

5. Method Description in Request Object

Note: If there is an unlisted Request object method, it means that the method is invalid in the scenario of batch getting data.

5.1. Method Description in Request Data Object

Note: If there is an unlisted Record object method, it means that the method is invalid in the scenario of batch getting data.

6. Method Description in Response Object

Note: If a Response object method is not listed, it means that the method is invalid in the scenario of reading data.

6.1. Method Description in Response Data Object

Note: If a Record object method is not listed, it means that the method is invalid in the scenario of reading data.

7. FAQ

For details, see Meaning and Handling of Error Codes.

8. Other Reference Documents

[[TDR Generic Table][C++ SDK] Interface Description for Batch-Getting Multiple Records](../../01C++_SDK/02Interface_Documents/08[Generic_Table]Batch_Get_Multiple_Records.md

[[TDR Generic Table] [Go SDK] Interface Description for Batch-Getting Multiple Records](../../03Go_SDK/02Interface_Documents/08[Generic_Table]Batch_Get_Multiple_Records.md

[TDR Generic Table] [MySQL Protocol Compatibility Interface] Interface Description for Querying Local Index.