覆盖Object中的clone方法， 实现深复制

public class Test {
	static class Body implements Cloneable {
		public Head head;

		public Body() {
		}

		public Body(Head head) {
			this.head = head;
		}

		@Override
		protected Object clone() throws CloneNotSupportedException {
			Body newBody = (Body) super.clone();
			newBody.head = (Head) head.clone();
			return newBody;
		}
	}

	static class Head implements Cloneable {
		public Face face;

		public Head() {
		}

		public Head(Face face) {
			this.face = face;
		}

		@Override
		protected Object clone() throws CloneNotSupportedException {
			return super.clone();
		}
	}

	static class Face implements Cloneable {
		public Face() {
		}
	}

	public static void main(String[] args) throws CloneNotSupportedException {
		Body body = new Body(new Head());
		Body body1 = (Body) body.clone();
		System.out.println("body == body1 : " + (body == body1));
		System.out.println("body.head == body1.head : " + (body.head == body1.head));
	}
}

body == body1 : false
body.head == body1.head : false