public class Node implements Comparable { private String keyword; private List references; public Node(String keyword, int mode){ this.keyword = keyword; if (mode == 1) { references = new ArrayList<>(); } else if (mode == 2) { references = new SortedArrayList<>(); } } public String getKeyword(){ return this.keyword; } public List getReferences(){ return this.references; } public void insertReference(String website){ this.references.add(website); } // TODO: Compare some other Node to this Node, String compareTo is your bestfriend here; return -1 if the other object of comparison isn't a Node public int compareTo(Object o){ return -1; }  // TODO: similar to compareTo except in boolean format and is only concerned if the other Node has the same keyword or not public boolean equals (Object o) { if (o instanceof Node) { Node other = (Node) o; return this.keyword.equals(other.keyword); } else return false; } public String toString(){ return this.keyword + " " + this.references; } }

Please answer TODO