Java Diary (3) class initialization problem (csdn a question)

Problem I added an output "7" to the original question, which is easy to explain the time when the parent class was initialized;

public class Test2 extends Test1 {
{
System.out.print ("1");
}

Test2 () {
System.out.print ("2");
}

static {
System.out.print ("3");
}

{
System.out.print ("4");
}

public static void Main (string[] args) {
New Test2 ();
}
}

Class Test1 {
{
System.out.print ("7");
}

Test1 () {
System.out.print ("5");
}

static {
System.out.print ("6");
}
}

Program execution Results: 6375142
Call Order:
1. Load the class first: Initialize the static variable, initialize the static variable of the parent class, then the static variable of the subclass;
2, initialization of the class: Before the subclass initialization, the initialization of the parent class, and the parent class constructor call;
3, the final initialization of the subclass, call the subclass construction method;

In Chinese Tij, it is not wrong to say that the constructor of the parent class executes before the constructor method of the subclass, but it is not

Perfect, the constructor of the parent class was executed before the subclass was initialized.