Java 如何在同一类中调用方法

我正在为一个电子邮件系统编写代码，我有一个小问题，我不知道如何调用一个方法

在main方法中调用writeAllofile方法的正确方法是什么

public class MailboxSystemSol{

    public static void main (String args[]) throws IOException{
    //code is too long to post here
    }

    public static void writeAllToFile(Userlist ul, User u, Message me){
    //code is too long to post here
    }

}

以下是UserList类：

/**
* Created by Broomhead0 on 4/11/14.
*/
import java.util.ArrayList;
public class Userlist
{
    ArrayList<User> users;  //this is an arraylist that will store references to all users

    public Userlist()
    {

        users = new ArrayList<User>();
    }

    // find a user in the list based on the username
    public User findUser(String username)
    {
        // iterate through the array; only iterate according to how many users are currently in     the array
        for (int i = 0; i < users.size(); i++)
        {
            // access the particular user through users.(i), then get the name,
            // and call the equals method on that name to compare it with the input username
            if (users.get(i).userName.equals(username)){
                return users.get(i);
            }

        }
        // no user found
        return null;
    }

    // add a user to the list; only do so if the user does not yet exist
    public void addUser(User u)
    {
        if (findUser(u.userName) != null) //if there is a match,
            System.out.println("User already exists");
        else //if there is not match
        {
           users.add(u); //add the username
        }

    }
    //check if this is correct
    //accessors
    public User getUser(int i){
        return users.get(i);
    }

    public int getNumUsers(){
        return users.size();
    }


}

下面是消息类：

/** *由Broomhead0于2014年4月11日创建。 */

---

你的问题回避了一个问题——你试过什么？这对你不起作用吗？您从哪里获取作为参数传递给方法的UserList、User和Message值？很抱歉，我应该指定，UserList、User和Message是其他类

WriteAllofile（您的\UL\U参数、您的\U\U参数、您的\U ME\U参数）它是一个静态方法，因此不需要实例化对象。您不需要包含类名，因为您是从定义它的同一个类中调用它的。我认为你最初提出的问题具有误导性。正如@WillNewton向您展示的那样，您已经知道如何在静态方法中调用静态方法，对吗？您的问题在于上面代码的细节，以及如何使用正确且有意义的参数调用此方法。如果是这样，您仍然需要弄清楚如何在主方法中创建User、UserList和Message对象，然后将它们传递到静态方法中。如果你仍然被卡住，你应该重新考虑你的问题，包括改变误导性的部分。
/**
 * Created by Broomhead0 on 4/11/14.
 */
public class User
{

    public String userName;  // the name of the user
    public Mailbox outbox; // reference to the mailbox of sent messages
    public Mailbox inbox;  // reference to the mailbox of received messages


    // create mailboxes according to the size given as input
    public User(String o, int boxsize) {
        userName = o;
        outbox = new Mailbox(boxsize);
        inbox = new Mailbox(boxsize);
    }

}

public class Message {

    // the properties of a message
    private String sender;
    private String receiver;
    private String subject;
    private String body;

    // all property values are known at creation of the message; so initialize
    public Message (String s, String r, String sub, String b)
    {
        sender = s;
        receiver = r;
        subject = sub;
        body = b;
    }

    // any nice format of printing the names and the values of the properties will do
    public void printMsg()
    {
        System.out.println("Sender: " + sender);
        System.out.println("Receiver: " + receiver);
        System.out.println("Subject: " + subject);
        System.out.println("Message: " + body);
    }

    // what follows are basic getter methods

    public String getSender()
    {
        return sender;
    }

    public String getReceiver()
    {
        return receiver;
    }

    public String getSubject()
    {
        return subject;
    }

    public String getBody()
    {
        return body;
    }

}

public class MailboxSystemSol{

    public static void main (String args[]) throws IOException{

        //define userlist, user and message variables..
        UserList userList = new UserList();
        User user = new User("Matthew", 1024);
        Message message = new Message("sender@gmail.com", "receiver@gmail.com", "Subject Content", "Body Content");

        //do something with declared variables...            

        writeAllToFile(userList, user, message);
    }

    public static void writeAllToFile(Userlist ul, User u, Message me){
        //code is too long to post here
    }

}