Who provides the default constructor in Java? Compiler or JVM?

Question

Is the constructor added at runtime or compile time? (I think this is compilation time). I need a detailed explanation, please, at the JVM architecture level.

I read various articles. Some say the compiler ... and others say the JVM. I want to be very sure (evidence will help a lot).

Sorry if the question is stupid (I'm still digesting terminology) !!!

Thanks in advance.

Answer 1

From a Java tutorial from Oracle: https://docs.oracle.com/javase/tutorial/java/javaOO/constructors.html

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Answer 2

:

• Java (JLS), 8.8.9
• Java, 2.12 .

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, , Java, JDK, , - .

$JDK_HOME/bin/

javap

Demo.java, ,

public class Demo {}

javac Demo.java, javap -c Demo, - :

Compiled from "Demo.java"
public class Demo {
  public Demo();
    Code:
       0: aload_0
       1: invokespecial #1                  // Method java/lang/Object."<init>":()V
       4: return
}

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public class Demo { 
  protected static class Other {}
}

, javap -c Demo.Other,

public class Demo$Other {
  protected Demo$Other();
    Code:
       0: aload_0
       1: invokespecial #1                  // Method java/lang/Object."<init>":()V
       4: return
}

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