When the Java virtual machine to initialize a class, asking it to all of the parent class have been initialized, but this rule is not suitable interfaces
1) When a class is initialized, and will not be initialized class interfaces it implements.
2) When initializing an interface, and will not be initialized its parent interface
Thus, a parent interface and sub-interface because it does not implement class initialization or initialized. Only when the program for the first time using the lens variable specific interface, will cause the initialization of the interface.
When a class is initialized, and will not be initialized interfaces it implements the class Sample
public class MyTest5 {
public static void main(String[] args) {
System.out.println(MyChild5.b);
}
}
interface MyParent5{
public static Thread thread = new Thread(){
{
//实例化代码块
System.out.println("MyParent 5 invoked ");
}
};
}
class MyChild5 implements MyParent5{
public static int b = 6;
}
Print results
6
If the access interface to change class
public class MyTest5 {
public static void main(String[] args) {
System.out.println(MyChild5.b);
}
}
class MyParent5{
public static Thread thread = new Thread(){
{
//实例化代码块
System.out.println("MyParent 5 invoked ");
}
};
}
class MyChild5 extends MyParent5{
public static int b = 6;
}
It will print out
MyParent 5 invoked this sentence.
At initialization interface, and it will not be initialized its parent interface
public class MyTest5 {
public static void main(String[] args) {
System.out.println(MyParent5_1.thread);
}
}
interface MyGrandpa5_1 {
public static Thread thread = new Thread(){
{
//实例化代码块
System.out.println("MyGrandpa5_1 invoked ");
}
};
}
interface MyParent5_1 {
public static Thread thread = new Thread(){
{
//实例化代码块
System.out.println("MyParent5_1 invoked ");
}
};
}
Print results
MyParent5_1 invoked Thread[Thread-0,5,main]