<dependency>
      <groupId>com.twilio.sdk</groupId>
      <artifactId>twilio-java-sdk</artifactId>
      <version>4.4.1</version>
      <scope>compile</scope>
   </dependency>

$ git clone git@github.com:twilio/twilio-java
$ cd twilio-java
$ mvn install       # Requires maven, download from http://maven.apache.org/download.html

package com.twilio.sdk.examples;

import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.ArrayList;
import java.util.Map;

import com.twilio.sdk.TwilioRestClient;
import com.twilio.sdk.TwilioRestException;
import com.twilio.sdk.TwilioRestResponse;
import com.twilio.sdk.resource.factory.CallFactory;
import com.twilio.sdk.resource.factory.SmsFactory;
import com.twilio.sdk.resource.instance.Account;
import com.twilio.sdk.resource.instance.AvailablePhoneNumber;
import com.twilio.sdk.resource.instance.Call;
import com.twilio.sdk.resource.instance.Conference;
import com.twilio.sdk.resource.instance.Participant;
import com.twilio.sdk.resource.list.AccountList;
import com.twilio.sdk.resource.list.AvailablePhoneNumberList;
import com.twilio.sdk.resource.list.ParticipantList;
import com.twilio.sdk.verbs.TwiMLException;
import org.apache.http.NameValuePair;
import org.apache.http.message.BasicNameValuePair;

public class Example {

  public static final String ACCOUNT_SID = "AC.....";
  public static final String AUTH_TOKEN = ".......";

  public static void main(final String[] args) throws TwilioRestException, TwiMLException {

    // Create a rest client
    final TwilioRestClient client = new TwilioRestClient(ACCOUNT_SID, AUTH_TOKEN);

    // Get the main account (The one we used to authenticate the client)
    final Account mainAccount = client.getAccount();

    // Get all accounts including sub accounts
    AccountList accountList = client.getAccounts();

    // All lists implement an iterable interface, you can use the foreach
    // syntax on them
    for (final Account a : accountList) {
      System.out.println(a.getFriendlyName());
    }

    // You can also iterate manually...
    final Iterator<Account> itr = accountList.iterator();
    while (itr.hasNext()) {
      final Account a = itr.next();
      System.out.println(a.getFriendlyName());
    }

    // You can also get just the first page of data
    accountList = client.getAccounts();
    final List<Account> accounts = accountList.getPageData();

    // Make a call
    final CallFactory callFactory = mainAccount.getCallFactory();
    final Map<String, String> callParams = new HashMap<String, String>();
    callParams.put("To", "5105551212"); // Replace with a valid phone number
    callParams.put("From", "(510) 555-1212"); // Replace with a valid phone number in your account
    callParams.put("Url", "http://demo.twilio.com/welcome/voice/");
    final Call call = callFactory.create(callParams);
    System.out.println(call.getSid());

    // Send an SMS (Requires version 3.4+)
    final SmsFactory messageFactory = mainAccount.getSmsFactory();
    final List<NameValuePair> messageParams = new ArrayList<NameValuePair>();
    messageParams.add(new BasicNameValuePair("To", "5105551212")); // Replace with a valid phone number
    messageParams.add(new BasicNameValuePair("From", "(510) 555-1212")); // Replace with a valid phone number in your account
    messageParams.add(new BasicNameValuePair("Body", "This is a test message!"));
    messageFactory.create(messageParams);

    // Search for available phone numbers & then buy a random phone number
    final AvailablePhoneNumberList phoneNumbers = mainAccount.getAvailablePhoneNumbers();
    final List<AvailablePhoneNumber> list = phoneNumbers.getPageData();

    // Buy the first number returned
    final Map<String, String> params = new HashMap<String, String>();
    params.put("PhoneNumber", list.get(0).getPhoneNumber());
    params.put("VoiceUrl", "http://demo.twilio.com/welcome/voice/");
    mainAccount.getIncomingPhoneNumberFactory().create(params);

    // View a conference using its sid
    final Conference c = mainAccount.getConference("CA12345...");
    final ParticipantList participants = c.getParticipants();

    for (final Participant p : participants) {
      // Randomly mute or kick each participant
      if (Math.random() > 0.5) {
        p.mute();
      } else {
        p.kick();
      }
    }

    // Make a raw HTTP request to the api... note, this is deprecated style
    final TwilioRestResponse resp = client.request("/2010-04-01/Accounts", "GET", null);
    if (!resp.isError()) {
      System.out.println(resp.getResponseText());
    }
  }
}