Preparation of this paper

See Chapter ： preparation .

Sample code

Sample code

import com.tencent.tcaplus.client.Client;
import com.tencent.tcaplus.client.ClientFactory;
import com.tencent.tcaplus.client.GenericTableTraverser;
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 environmental information 
        // 1.1.  Directory service 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.  Business ID
        int appId = 1;
        // 1.3.  Business password 
        String appPassword = "****************";
        // 1.4.  Table group ID
        int tableGroupId = 1;
        // 1.5.  Table name 
        String tableName = "test";
​
        // 2.  Create client 
        Client client = ClientFactory.createClient(appId, tableGroupId, appPassword, dirList);
        try {
            // 3.  The structure is based on part Key A request to read data from a field value 
            // 3.1.  Get request object . In order to improve SDK performance ,Request Objects are reusable 
            Request request = client.acquireRequest();
            // 3.2.  establish 1 Scanners 
            GenericTableTraverser traverser = client.getGenericTableTraverser(tableName);
            // 3.3.  Add the data to be read Value Field 
            traverser.addFieldName("typeid");
            traverser.addFieldName("Data");
            traverser.addFieldName("uname");
            // 3.4.  Set the maximum number of data pieces returned in a batch , Because the amount of data returned by scanning is usually large , Batch return required 
            traverser.setLoadOptions(100);
            // 3.5.  Set the maximum number of data returned in total 
            traverser.setTotalLimit(10000);
​
            CountDownLatch latch = new CountDownLatch(1);
​
            // 4.  Start the scanner asynchronously , And specify the processor that returns the result 
            traverser.startAsync(new Future() {
​
                @Override
                public void onResponse(Response response) {
                    // 5.  Processing results 
                    if (response.getResult() == 0) {
                        for (Record result : response.getRecordList()) {
                            // TODO  You can add processing data codes here 
                        }
                    }
                    if (traverser.isCompleted()) {
                        latch.countDown();
                    }
                }
​
            });
​
            latch.await();
        } finally {
            // 6.  Destroy client objects 
            ClientFactory.destroyClient(client);
        }
    }

TcaplusDB It's a distributed product of Tencent NoSQL database , The code for storage and scheduling is completely self-developed . With cache + Landing fusion architecture 、PB Levels of storage 、 Millisecond delay 、 Lossless horizontal expansion and complex data structure . At the same time, it has rich ecological environment 、 Easy migration 、 Extremely low operation and maintenance costs and five nine high availability features . Customer coverage game 、 Internet 、 government affairs 、 Finance 、 Manufacturing and the Internet of things .