APL/DEV 3.2/TP08/Tri/TreeNode.java

public class TreeNode<T> {

    private T value;
    private TreeNode<T> lesser;
    private TreeNode<T> greater;
    private SearchTree<T> parentTree;

    public TreeNode(SearchTree<T> parentTree, T object) {
        this.parentTree = parentTree;
        this.value = object;
    }

    public void add(T object) {
        switch (parentTree.getComparator().compare(value, object)) {
            case -1:
                if (lesser != null) lesser.add(object);
                else lesser = new TreeNode<T>(parentTree, object);
                break;
            case 0:
                throw new IllegalArgumentException("Value already in tree");
            case 1:
                if (greater != null) greater.add(object);
                else greater = new TreeNode<T>(parentTree, object);
                break;
        }
    }

    public void remove(T object) {
        if (lesser.getValue().equals(object)) {
            T a = lesser.getLesser().getValue();
            T b = lesser.getGreater().getValue();
            parentTree.add(a);
            parentTree.add(b);
            lesser = null;
        } else if (greater.getValue().equals(object)) {
            T a = greater.getLesser().getValue();
            T b = greater.getGreater().getValue();
            parentTree.add(a);
            parentTree.add(b);
            greater = null;
        } else {
            switch (parentTree.getComparator().compare(value, object)) {
                case -1:
                    if (lesser != null) lesser.remove(object);
                    else return;
                    break;
                case 0:
                    throw new IllegalStateException("Something fucked up");
                case 1:
                    if (greater != null) greater.remove(object);
                    else return;
                    break;
            }
        }
    }

    public T getValue() {
        return value;
    }

    public TreeNode<T> getLesser() {
        return lesser;
    }

    public TreeNode<T> getGreater() {
        return greater;
    }

    @Override
    public String toString() {
        String str = "";
        if (greater != null) str += greater.toString();
        str += value.toString() + " ";
        if (lesser != null) str += lesser.toString() + " ";

        return str;
    }
}