How do I add multiple object to an arraylist from a form?

Question

0.00/5 (No votes)

See more:

I have a class called User and a arrayList

ArrayList<User> users = new ArrayList<>();

I have already put in one user like this:

User newUser = new User("sunn", "1998");
            User.users.add(newUser);

But then I will get the next users from a form you can fill out.

User newUser = new User(username, year);

User.users.add(newUser);

It is not possible to use the identifier newUser everytime, but how can I make a identifier to a unknow amount of users? I would really like to have the identifier as the same as the username, but how do I do this?

What I have tried:

User newUser = new User(username, year);

User.users.add(newUser);

It is not possible to use the identifier newUser everytime, but how can I make a identifier to a unknow amount of users? I would really like to have the identifier as the same as the username, but how do I do this?

Posted 31-Oct-18 0:05am

Member 14039072

Updated 31-Oct-18 0:36am

v2

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Richard MacCutchan · Answer 1 · 2018-10-31T00:37:00

Solution 1

Why is it not possible? It is quite valid to do this:

Java

User newUser;
while (some condition) {
    newUser = new User(username, year);
    User.users.add(newUser);
}

// or you could do

while (some condition) {
    User.users.add(new User(username, year));
}

Posted 31-Oct-18 0:37am

Richard MacCutchan

Comments

Member 14039072 31-Oct-18 6:44am

Thanks, but how can I make the "indentifier" of the object to be the username that is filled in? Because later I want be able to easily delete an object by the username.

Richard MacCutchan 31-Oct-18 6:51am

You do not need to do that, you just search the arraylist for the specific username and delete the entry. Have a look at ArrayList (Java Platform SE 8 )[^] for more information. Alternatively use one of the keyed collections such as Dictionary (Java Platform SE 8 )[^].

CPallini 31-Oct-18 8:19am

5.