How do I loop through an array in Java?

Question

Related to my question about how to build a tree-like structure, the data I receive from the server are in arrays like this: {School Chair Table Chalk}

How can I loop through this so that:

• School becomes parent of Chair
• Chair becomes parent of Table
• Table becomes parent of Chalk

Answer 1

Assuming a Node class that offers a constructor which accepts the node's value as an argument and method addChild that adds another Node as a child and sets itself as the child's parent, the code could look like this:

Node currentNode = null;
for(String value: array) {
    Node node = new Node(value);
    if(currentNode != null) {
        currentNode.addChild(node);
    }
    currentNode = node;
}

Answer 2

Are they always in a list that becomes hierarchical in order? I would suggest creating a simple wrapper class...pardon my syntax, as I've been playing in C# for a while now:

public class Node {
    public string description;
    public Node child;

    public Node(List<string> descriptions) {

        this.description = descriptions.RemoveAt(0);
        if (descriptions.Count > 0) {
            this.child = new Node(descriptions);  //create child node with remaining items
        }
    }
}

This will take issue if you pass in a list w/ zero items to the constructor, but that's easily remedied.