Question

In C#, I can create an instance of every custom class that I write, and pass values for its members, like this:

public class MyClass
{
    public int number;
    public string text;
}

var newInstance = new MyClass { number = 1, text = "some text" };

This way of creating objects is called object creation expressions. Is there a way I can do the same in Java? I want to pass values for arbitrary public members of a class.

Answer 1

No, there’s nothing directly similar. The closest you can come in Java (without writing a builder class etc) is to use an anonymous inner class and initializer block, which is horrible but works:

MyClass foo = new MyClass()
{{
    number = 1;
    text = "some text";
}};

Note the double braces… one to indicate “this is the contents of the anonymous inner class” and one to indicate the initializer block. I wouldn’t recommend this style, personally.