[TDR List Table][Java SDK] Delete an Element from a Specified Position in a List

1. Interface Description

Delete data from a specified position in a list of a specified Key in a table.

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 List 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. Create a request to query data
            // 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. Note: The target table must be a List table
            request.setCmd(TcaplusProtocolCsConstants.TCAPLUS_CMD_LIST_DELETE_REQ);
            request.setTableName(tableName);
            // 3.3. Because multiple records with the same Key can exist in the List table,
            //      You need to specify which data to delete from the data list. In this sample, 0 means to fetch the first data, and so on
            Record record = request.addRecord(0);
            // 3.4. Set the value of each Key field in the list
            record.setKeyInt("gameid", 1);
            record.setKeyInt("itemid", 1);
            record.setKeyString("name", "test");

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

            // 5. Process the result
            if (response.getResult() == 0) {
                // Data deleting successful
                // TODO: add the code to process the result of data deleting successful here
            } else {
                // Data deleting failure
                // TODO: add the code to process the result of data deleting 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. Create a request to query data
            // 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. Note: The target table must be a List table
            request.setCmd(TcaplusProtocolCsConstants.TCAPLUS_CMD_LIST_DELETE_REQ);
            request.setTableName(tableName);
            // 3.3. Because multiple records with the same Key can exist in the List table,
            //      You need to specify which data to delete from the data list. In this sample, 0 means to fetch the first data, and so on
            Record record = request.addRecord(0);
            // 3.4. Set the value of each Key field in the list
            record.setKeyInt("gameid", 1);
            record.setKeyInt("itemid", 1);
            record.setKeyString("name", "test");

            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 deleting 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 deleting data.

6. Method Description in Response Object

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

7. FAQ

For details, see Meaning and Handling of Error Codes.

8. Other Reference Documents

[TDR List Table][C++ SDK] Interface Description for Deleting an Element from a Specified Position in a List

[TDR List Table] [Go SDK] Interface Description for Deleting an Element from a Specified Position in a List