Java Constructor sequence discuss | Java構造函數順序小記

Class的構造順序可以從編譯的角度去了解，突然想到一個非常好的例子來說明這個問題

package com.cachetian.scjp;

public class MyChildObj {
	public MyChildObj() {
		System.out.println("My Child Obj Constructes");
	}
}
           

package com.cachetian.scjp;

public class MyObj extends MyFatherObj{
	
	protected MyChildObj child = new MyChildObj();
	
	public MyObj() {
		System.out.println("My Obj Constructed");
	}
	
	public static void main(String[] args) {
		new MyObj();
	}
}
           

package com.cachetian.scjp;

public class MyFatherObj extends MyGrandFatherObj{
	
	public MyFatherObj() {
		System.out.println("My Father Obj Constructed");
	}
}
           

package com.cachetian.scjp;

public class MyUncleObj {
	public MyUncleObj() {
		System.out.println("My Uncle Constructed");
	}
}
           

package com.cachetian.scjp;

public class MyGrandFatherObj {
	
	protected MyUncleObj myUncle = new MyUncleObj();
	
	public MyGrandFatherObj() {
		System.out.println("My Grandfather Constructed");
	}
}
           

運作結果：

My Uncle Constructed
My Grandfather Constructed
My Father Obj Constructed
My Child Obj Constructes
My Obj Constructed