java class 初始化

the order of execution is: static initializer, instance initializer, constructor 

1.Initializing Fields

public class BedAndBreakfast {

    // initialize to 10
    public static int capacity = 10;

    // initialize to false
    private boolean full = false;
}

2.Static Initialization Blocks

static {
    // whatever code is needed for initialization goes here
}

3.Initializing Instance Members

{
    // whatever code is needed for initialization goes here
}

4. constructor

5. example

public class t1 {

    {
        System.out.println("Empty block");
    }
    static {
        System.out.println("Static block");
    }

    public t1() {
        System.out.println("constructor block");
    }

    public static void main(String[] args) {
        t1 t = new t1();
    }
}

http://docs.oracle.com/javase/tutorial/java/javaOO/initial.html Initializing Fields

http://www.javatpoint.com/instance-initializer-block  Instance initializer block: