Java中的对象初始化-术语

Question

I came across this blog, and they used term Anonymous object instantiation

Is it really an "official term" or not?

In any case, what is the official terminology for that kind of code: calling a method without explicitly creating object with its name like in this example (UPDATE: I am referring to explicitly giving a name to object not explicitly creating object) :

public class Predictions3Client {
    public static void main(String[]  args) {
        new Predictions3Client().demo();
    }

    private void demo() {
        Localhost_Predictions3ResourcesP.Root root = Localhost_Predictions3ResourcesP.root();
        Localhost_Predictions3ResourcesP.Root.Xml xmlGetter = root.xml();
        String xml = xmlGetter.getAsXml(String.class); 
        System.out.println("The raw XML:\n" + xml);   
    }
}

new Predictions3Client().demo();

vs

Predictions3Client p3c = new Predictions3Client ();
p3c.demo();

I don't consider that as "method chaining" or "Fluent interface" as it is object related not method related.

Answer 1

In Java Anonymous objects are objects that don't have class names or have abstract class names. In short, you must fill in the "missing" methods to build the class, and those "missing" methods aren't tied to a class name.

   Runnable runnable = new Runnable() {
      public void run() {
         System.out.println("Hi, I'm anonymous!");
      }
   }

is an example. If it was a fully named class, it would look like

 public class HelloRunnable implements Runnable {
      public void run() {
         System.out.println("Hi, I'm not anonymous, I'm a HelloRunnable!");
      }
 }

Note that anonymous classes are still constructed, but they are constructed with the missing methods as parameters (they're supplied between the curly braces). So, technically you are still "creating" a class, and you are still "creating an instance" of a class, but that class has no single, uniquely identifiable class name.

Hence the "anonymous object instantiation" which I would have referred to by the simpler phrase "anonymous object creation"

Keep in mind that the first example's class name is not properly referred to as a "Runnable" class because not all runnables will print out "Hi, I'm anonymous" as demonstrated in the example below.

   Runnable runnable = new Runnable() {
      public void run() {
         System.out.println("Hi, I'm anonymous!");
      }
   }
   runnable = new Runnable() {
      public void run() {
         System.out.println("Hi, I'm anonymous's cousin!");
      }
   }

However, in the example above, it is proper to call both classes a Runnable, because they both implement the runnable interface.