Java树实现父和子概念

public class TreeNode {
    private int value;
    private List<TreeNode> children;

    public TreeNode(int value) {
        this.value = value;
        this.children = new ArrayList<>();
    }

    public int getValue() {
        return value;
    }

    public List<TreeNode> getChildren() {
        return children;
    }

    public void addChild(TreeNode child) {
        children.add(child);
    }
}

TreeNode root = new TreeNode(1);
TreeNode child1 = new TreeNode(2);
TreeNode child2 = new TreeNode(3);
TreeNode grandchild1 = new TreeNode(4);
TreeNode grandchild2 = new TreeNode(5);

root.addChild(child1);
root.addChild(child2);
child1.addChild(grandchild1);
child2.addChild(grandchild2);