GetSentMessages.java

int pageNumber = 1;
int pageSize = 20;

UserPassword userPassword = new UserPassword("YourUsername","YourPassword");
BasicServiceFactory serviceFactory = ServiceFactory.createBasicAuthenticatingFactory(userPassword);
SentService sentService = serviceFactory.getSentService();

SentMessageCollectionResponse sentMessages;
try{
    sentMessages = sentService.getMessages(pageNumber, pageSize);
}catch(Exception e){
    e.getStackTrace();
}