How to retrieve location information based on an IP address in Java?

In Java, third-party libraries like GeoIP2 and ip2region can be used to retrieve the location based on an IP address.

1. Utilize the GeoIP2 library:

Firstly, you need to download the GeoIP2 Java library and then use it in your code to retrieve the location of an IP address.

import com.maxmind.geoip2.DatabaseReader;
import com.maxmind.geoip2.model.CityResponse;
import java.io.File;
import java.net.InetAddress;

public class IPUtil {

    public static void main(String[] args) throws Exception {
        File database = new File("/path/to/GeoLite2-City.mmdb");
        DatabaseReader reader = new DatabaseReader.Builder(database).build();

        InetAddress ipAddress = InetAddress.getByName("128.101.101.101");
        CityResponse response = reader.city(ipAddress);

        String country = response.getCountry().getName();
        String city = response.getCity().getName();

        System.out.println("Country: " + country);
        System.out.println("City: " + city);
    }
}

1. Utilize the ip2region library.

ip2region is a Java implementation of a pure IP database, which allows for fast retrieval of location information based on an IP address.

import org.lionsoul.ip2region.*;
import java.io.IOException;

public class IPUtil {

    public static void main(String[] args) throws DbMakerConfigException, IOException {
        DbConfig config = new DbConfig();
        DbSearcher searcher = new DbSearcher(config, "/path/to/ip2region.db");

        DataBlock dataBlock = searcher.btreeSearch("128.101.101.101");

        String region = dataBlock.getRegion();

        System.out.println("Region: " + region);
    }
}

The above are two commonly used methods to choose the appropriate tool for obtaining the geographical location of an IP address based on specific needs.