devtools devtools=(chromedriver).driver
package com.devtools;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.devtools.DevTools;
import org.openqa.selenium.devtools.network.Network;
import org.openqa.selenium.devtools.network.model.ConnectionType;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;
public class SetNetwork {
    final static String PROJECT_PATH = System.getProperty("user.dir");
    public static void main(String[] args){
        System.setProperty("webdriver.chrome.driver", PROJECT_PATH + "/src/main/resources/chromedriver");
        ChromeDriver driver;
        driver = new ChromeDriver();
        
        DevTools devTools = driver.getDevTools();
        devTools.createSession();
        devTools.send(Network.enable(Optional.empty(), Optional.empty(), Optional.empty()));
        devTools.send(Network.emulateNetworkConditions(
                false,
                20,
                20,
                50,
                Optional.of(ConnectionType.CELLULAR2G)
        ));
        driver.get("https://www.google.com");
    }
}
