Java读取InfluxDB数据库的方法详解

<dependencies>
    <dependency>
        <groupId>org.influxdb</groupId>
        <artifactId>influxdb-java</artifactId>
        <version>2.8</version>
    </dependency>
</dependencies>

import org.influxdb.InfluxDB;
import org.influxdb.InfluxDBFactory;
import org.influxdb.dto.Query;
import org.influxdb.dto.QueryResult;
import org.jetbrains.annotations.NotNull;

import java.util.List;
import java.util.Scanner;

public class Main {
    private static final String url = "http://127.0.0.1:8086";
    private static final String username = "root";
    private static final String password = "";

    public static void main(String[] args) {
        InfluxDB influxDB = InfluxDBFactory.connect(url, username, password);
        showDatabases(influxDB);
        showMeasurements(influxDB);
        showData(influxDB);
    }

    // Show database(s)
    private static void showDatabases(InfluxDB influxDB) {
        QueryResult queryResult = influxDB.query(new Query("SHOW DATABASES"));
        QueryResult.Series series = queryResult.getResults().get(0).getSeries().get(0);
        List<List<Object>> databaseList = series.getValues();
        System.out.println("Database(s) is(are):");
        for (List<Object> innerList: databaseList) {
            for (Object object: innerList) {
                System.out.println(object);
            }
        }
        System.out.println();
    }

    // Show measurement(s)
    private static void showMeasurements(InfluxDB influxDB) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Please enter the database name: ");
        String databaseName = scanner.nextLine();

        try {
            List<List<Object>> measurementsList = influxDB.query(new Query("SHOW MEASUREMENTS ON " + databaseName)).getResults().get(0).getSeries().get(0).getValues();
            System.out.println("Measurement(s) for " + databaseName + " is(are):");
            for (List<Object> innerList: measurementsList) {
                for (Object object: innerList) {
                    System.out.println(object);
                }
            }
            System.out.println();
            showTagKeys(influxDB, databaseName);
            showTagValues(influxDB, databaseName);
            showFieldKeys(influxDB, databaseName);
        } catch (Exception e) {
            System.out.println("Measurement(s) for " + databaseName + " is empty!");
            return;
        }
    }

    // Show tag keys
    private static void showTagKeys(InfluxDB influxDB, String databaseName) {
        List<List<Object>> tagKeysList = influxDB.query(new Query("SHOW TAG KEYS ON " + databaseName)).getResults().get(0).getSeries().get(0).getValues();
        System.out.println("Tag Key(s) for " + databaseName + " is(are):");
        for (List<Object> innerList: tagKeysList) {
            for (Object object: innerList) {
                System.out.println(object);
            }
        }
        System.out.println();
    }

    // Show tag values
    private static void showTagValues(InfluxDB influxDB, String databaseName) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Please enter the tag key name: ");
        String TagKey = scanner.nextLine();

        List<List<Object>> tagValuesList = influxDB.query(new Query("SHOW TAG VALUES ON " + databaseName + " WITH KEY = " + TagKey)).getResults().get(0).getSeries().get(0).getValues();
        System.out.println("Tag Value(s) is(are):");
        for (List<Object> innerList: tagValuesList) {
            System.out.println(innerList.get(0) + ": " + innerList.get(1));
        }
        System.out.println();
    }

    // Show field keys
    private static void showFieldKeys(InfluxDB influxDB, String databaseName) {
        List<List<Object>> fieldKeysList = influxDB.query(new Query("SHOW FIELD KEYS ON " + databaseName)).getResults().get(0).getSeries().get(0).getValues();
        System.out.println("Field Key(s) and Type(s) are:");
        for (List<Object> innerList: fieldKeysList) {
            System.out.println(innerList.get(0) + ": " + innerList.get(1));
        }
        System.out.println();
    }

    // Show data
    private static void showData(@NotNull InfluxDB influxDB) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Please enter the database name: ");
        String databaseName = scanner.nextLine();

        System.out.print("Please enter the measurements name: ");
        String measurementName = scanner.nextLine();

        influxDB.setDatabase(databaseName);
        QueryResult dataResult = influxDB.query(new Query("SELECT * FROM " + measurementName));
        System.out.println(dataResult);
    }
}