谁能给点思路，这个问题我一点思路也没有

public static class BodyPart { private String name; public BodyPart(String name) { this.name = name; } public Object containsBones(){ return "是"; } public String toString() { if(this.containsBones().equals("是")){ return name + " 包含骨骼" ;} else if(this.containsBones().equals("否")){ return name + " 不包含骨骼";} return ""; } } public static class Finger extends BodyPart { private boolean isArtificial; public Finger(String name, boolean isArtificial) { super(name); this.isArtificial = isArtificial; } public Object containsBones() { if (super.containsBones().equals("是") && !isArtificial){ return "是";} else { return "否";} } } public static void main(String[] args) { printlnFingers(); printlnBodyParts(); printlnLivingParts(); } private static void printlnLivingParts() { System.out.println(new BodyPart("手").containsBones()); } private static void printlnBodyParts() { List<BodyPart> bodyParts = new ArrayList<>(5); bodyParts.add(new BodyPart("手")); bodyParts.add(new BodyPart("腿")); bodyParts.add(new BodyPart("头")); bodyParts.add(new BodyPart("身体")); System.out.println(bodyParts.toString()); } private static void printlnFingers() { List<Finger> fingers = new ArrayList<>(5); fingers.add(new Finger("大拇指", true)); fingers.add(new Finger("食指", true)); fingers.add(new Finger("中指", true)); fingers.add(new Finger("无名指", false)); fingers.add(new Finger("小拇指", true)); System.out.println(fingers.toString()); }

我也不懂這題到底怎麼做

先修改 LivingPart 的 containsBones 的返回值类型为 Object