Question

Been searching for a solution to my problem. Been reading a lot about overriding equals to properly compare nodes of a linked list but have become stuck. Basically I am trying to search through my list and find a node that equals it and delete it. I have found the way to look through the linked list but when I return the node it is just gibberish. I am trying to find a way to get it into a string and compare it to another string. Anyway here is the code and my equals method that currently does not work.

public class MagazineList {
    private MagazineNode list;
    private Object obj;

    public MagazineList(){
        list = null;
    }


    public void add(Magazine mag){
        MagazineNode node = new MagazineNode(mag);
        MagazineNode current;

        if(list==null)
            list = node;
        else{
            current = list;
            while(current.next != null)
                current = current.next;
            current.next = node;
        }   
    }
    public void insert(Magazine mag)
    {
        MagazineNode node = new MagazineNode (mag);

        // make the new first node point to the current root
        node.next=list;

        // update the root to the new first node
        list=node;
    }
    public void deleteAll(){
        if(list == null){

        }
        else{
            list = null;
        }
    }

    public void delete (Magazine mag) {
        MagazineNode current = this.list;
        MagazineNode before;

        //if is the first element
        if (current.equals(mag)) {
            this.list = current.next;
            return;     //ending the method
        }


        before = current;

        //while there are elements in the list
        while ((current = current.next) != null) {

            //if is the current element
            if (current.equals(mag)) {
                before.next = current.next;
                return;     //endind the method 
            }

            before = current;
        }

        //it isnt in the list
    }
    public boolean equals(Object other) {

        System.out.println("Here in equals" + other + this);
        // Not strictly necessary, but often a good optimization
        if (this == other)
            return true;
        else{
            return false;
        }
    }

    @ Override
    public String toString(){
        String result = " ";

        MagazineNode current = list;
        while (current != null){
            result += current.magazine + "\n";
            current = current.next;     
        }
        return result;
    }


    private class MagazineNode {
        public Magazine magazine;
        public MagazineNode next;


        public MagazineNode(Magazine mag){
            magazine = mag;
            next = null;
        }
    }
}

Answer 1

Your delete method looks fine, except you shouldn’t compare a MagazineNode with a Magazine. You should compare a Magazine with a Magazine.

Replace if (current.equals(mag)) by if (current.magazine.equals(mag)).