组合模式

组合模式：核心思想是解决树形结构，将一个复杂的对象简单化。典型的应用就是树形结构的应用。

例：目录结构、组织架构这类问题都可以使用组合模式解决。

具体代码如下:

 

package com.mkf.pattern;

import java.util.Enumeration;
import java.util.Vector;

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
	 * 
	 * @param node
	 */
	public void addChildren(TreeNode node) {
		children.add(node);
		node.setParent(this);
	}

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

	/**
	 * 获得子节点
	 * 
	 * @return
	 */
	public Enumeration<TreeNode> getChildren() {
		return children.elements();
	}

	@Override
	public String toString() {
		return "TreeNode [parent=" + (null == parent ? "" : parent.getName()) +
			", name=" + name
				+ ", children" + children.toString() + "]";
	}
	
}

测试

 

package com.mkf;

import com.mkf.pattern.TreeNode;

public class TestComposite {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		TreeNode root = new TreeNode("ROOT");
		TreeNode node11 = new TreeNode("NODE11");
		TreeNode node12 = new TreeNode("NODE12");
		TreeNode node1121 = new TreeNode("NODE1121");
		TreeNode node1122 = new TreeNode("NODE1122");
		TreeNode node1221 = new TreeNode("NODE1221");
		TreeNode node1222 = new TreeNode("NODE1222");
		root.addChildren(node11);
		root.addChildren(node12);
		node11.addChildren(node1121);
		node11.addChildren(node1122);
		node12.addChildren(node1221);
		node12.addChildren(node1222);
		System.out.println(root.toString());
	}

}

输出结果：

TreeNode [parent=, name=ROOT, children[
 TreeNode [parent=ROOT, name=NODE11, children[
  TreeNode [parent=NODE11, name=NODE1121, children[]],
  TreeNode [parent=NODE11, name=NODE1122, children[]]
      ]
  ],
 TreeNode [parent=, name=NODE12, children[
  TreeNode [parent=NODE12, name=NODE1221, children[]],
  TreeNode [parent=NODE12, name=NODE1222, children[]]
      ]
  ]
     ]
]