Connecting to an Instance Using Java

This section describes how to connect to a GeminiDB Influx instance using the Java programming language.

Dependencies on the pom File

<dependency>
  <groupId>org.influxdb</groupId>
  <artifactId>influxdb-java</artifactId>
  <version>2.21</version>
</dependency>

Example Code for Connecting to an Instance Using SSL

package influxdb;

 import java.security.SecureRandom;
 import java.security.cert.X509Certificate;
 import java.util.concurrent.TimeUnit;
 import javax.net.ssl.SSLContext;

 import okhttp3.OkHttpClient;
 import org.influxdb.InfluxDB;
 import org.influxdb.InfluxDBFactory;
 import org.influxdb.dto.Point;
 import org.influxdb.dto.Query;
 import org.influxdb.dto.QueryResult;

 import org.apache.http.ssl.SSLContexts;
 import javax.net.ssl.*;

 public class demo {
     public static void main(String[] args) {
         OkHttpClient.Builder client = new OkHttpClient.Builder()
             .connectTimeout(10, TimeUnit.SECONDS)
             .writeTimeout(10, TimeUnit.SECONDS)
             .readTimeout(10, TimeUnit.SECONDS)
             .retryOnConnectionFailure(true);

         client.sslSocketFactory(defaultSslSocketFactory(), defaultTrustManager());
         client.hostnameVerifier(noopHostnameVerifier());

         final String serverURL = "https://127.0.0.1:8086", username = "root", password = "root";

         InfluxDB influxdb = InfluxDBFactory.connect(serverURL, username, password, client);

         // Create a database...
         String databaseName = "foo";
         influxdb.query(new Query("CREATE DATABASE " + databaseName, databaseName));
         influxdb.setDatabase(databaseName);

         // Write points to influxdb.
         influxdb.write(Point.measurement("bar")
             .time(System.currentTimeMillis(), TimeUnit.MILLISECONDS)
             .tag("location", "chengdu")
             .addField("temperature", 22)
             .build());

         // Query your data using InfluxQL.
         QueryResult queryResult = influxdb.query(new Query("SELECT * FROM bar", databaseName));

         // Close it if your application is terminating or you are not using it anymore.
         influxdb.close();
     }

     private static X509TrustManager defaultTrustManager() {
         return new X509TrustManager() {
             public X509Certificate[] getAcceptedIssuers() {
                 return new X509Certificate[0];
             }

             public void checkClientTrusted(X509Certificate[] certs, String authType) {
             }

             public void checkServerTrusted(X509Certificate[] certs, String authType) {
             }
         };
     }

     private static SSLSocketFactory defaultSslSocketFactory() {
         try {
             SSLContext sslContext = SSLContexts.createDefault();

             sslContext.init(null, new TrustManager[] {
                 defaultTrustManager()
             }, new SecureRandom());
             return sslContext.getSocketFactory();
         } catch (Exception e) {
             throw new RuntimeException(e);
         }

     }

     private static HostnameVerifier noopHostnameVerifier() {
         return new HostnameVerifier() {
             @Override
             public boolean verify(final String s, final SSLSession sslSession) { 
                 return true; //true indicates that SSL is enabled but the SSL certificate is not verified. This mode is recommended.
             }
         };
     }
 }

Example Java Code for Connecting to an Instance Using an Unencrypted Connection

package influxdb;

import okhttp3.OkHttpClient;
import org.influxdb.InfluxDB;
import org.influxdb.InfluxDBFactory;
import org.influxdb.dto.Point;
import org.influxdb.dto.Query;
import org.influxdb.dto.QueryResult;

import java.util.concurrent.TimeUnit;

public class demoNoSSL {
    public static void main(String[] args) {
        OkHttpClient.Builder client = new OkHttpClient.Builder()
                .connectTimeout(10, TimeUnit.SECONDS)
                .writeTimeout(10, TimeUnit.SECONDS)
                .readTimeout(10, TimeUnit.SECONDS)
                .retryOnConnectionFailure(true);

        final String serverURL = "http://127.0.0.1:8086", username = "root", password = "root";
        InfluxDB influxdb = InfluxDBFactory.connect(serverURL, username, password, client);

        // Create a database...
        String databaseName = "foo";

        influxdb.query(new Query("CREATE DATABASE " + databaseName, databaseName));
        influxdb.setDatabase(databaseName);

        // Write points to influxdb.
        influxdb.write(Point.measurement("bar")
                .time(System.currentTimeMillis(), TimeUnit.MILLISECONDS)
                .tag("location", "chengdu")
                .addField("temperature", 22)
                .build());

        // Query your data using InfluxQL.
        QueryResult queryResult = influxdb.query(new Query("SELECT * FROM bar", databaseName));

        // Close it if your application is terminating or you are not using it anymore.
        influxdb.close();
    }
}

Example Java Code for Connecting to an Instance Using the Connection Pool

package influxdb;

import okhttp3.ConnectionPool;
import okhttp3.OkHttpClient;
import org.influxdb.InfluxDB;
import org.influxdb.InfluxDBFactory;
import org.influxdb.dto.Point;
import org.influxdb.dto.Query;
import org.influxdb.dto.QueryResult;

import java.util.concurrent.TimeUnit;

public class demoConnectionPool {
    public static void main(String[] args) {
        // The client connection pool is based on OkHttpClient.
        OkHttpClient.Builder client = new OkHttpClient().newBuilder();
        client.connectTimeout(10, TimeUnit.SECONDS);
        client.readTimeout(10, TimeUnit.SECONDS);
        client.writeTimeout(10, TimeUnit.SECONDS);
        // Set this parameter to true to mask some connection errors so that the system automatically retries.
        client.retryOnConnectionFailure(true);
        // Maximum number of idle connections in the connection pool. The default value is 5.
        // The connection that stays idle longer than the threshold will be disabled by the connection pool. Then sockets enter into the TIME_WAIT status for the system to reclaim. Set parameter new ConnectionPool based on the number of the idle connections.
        client.connectionPool(new ConnectionPool(5, 30, TimeUnit.SECONDS));

        final String serverURL = "http://127.0.0.1:8086", username = "root", password = "root";
        InfluxDB influxdb = InfluxDBFactory.connect(serverURL, username, password, client);

        // Create a database...
        String databaseName = "foo";

        influxdb.query(new Query("CREATE DATABASE " + databaseName, databaseName));
        influxdb.setDatabase(databaseName);

        // Write points to influxdb.
        influxdb.write(Point.measurement("bar")
                .time(System.currentTimeMillis(), TimeUnit.MILLISECONDS)
                .tag("location", "chengdu")
                .addField("temperature", 22)
                .build());

        // Query your data using InfluxQL.
        QueryResult queryResult = influxdb.query(new Query("SELECT * FROM bar", databaseName));

        // Close it if your application is terminating or you are not using it anymore.
        influxdb.close();
    }
}

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