[设计模式]组合模式(Composite) treenode

时间:2021-10-23 12:38:08

组合模式有时又叫部分-整体模式在处理类似树形结构的问题时比较方便,看看关系图:

直接来看代码:

public class TreeNode {  

private String name;
private TreeNode parent;
private Vector<TreeNode> children = new Vector<TreeNode>();

public TreeNode(String name){
this.name = name;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public TreeNode getParent() {
return parent;
}

public void setParent(TreeNode parent) {
this.parent = parent;
}

//添加子节点
public void add(TreeNode node){
children.add(node);
}

//删除子节点
public void remove(TreeNode node){
children.remove(node);
}

//取得所有子节点
public Enumeration<TreeNode> getChildren(){
return children.elements();
}
}

public class Tree {  

TreeNode root = null;

public Tree(String name) {
root = new TreeNode(name);
}

public static void main(String[] args) {
Tree tree = new Tree("A");
TreeNode nodeB = new TreeNode("B");
TreeNode nodeC = new TreeNode("C");

nodeB.add(nodeC);
tree.root.add(nodeB);
System.out.println("build the tree finished!");
}
}

使用场景:将多个对象组合在一起进行操作,常用于表示树形结构中,例如二叉树,数等。