无序的Tree格式的List，转化打印出标准格式Treelist

import java.util.ArrayList;
import java.util.List;

/**
 * 
 * @author zyengogo
 *
 */
public class TreeList {
	static List newList=new ArrayList();
	
	//获得子节点
	public static List<TreePojo> getChild(TreePojo treeNode,List treeList){
		List<TreePojo> childList = new ArrayList<TreePojo>();
		for(int i = 0 ;i<treeList.size();i++){
			if(treeNode.treeid == ((TreePojo)treeList.get(i)).getPid()){
				childList.add((TreePojo)treeList.get(i));
			}
		}
		return childList;
	}

	//获得根节点
	public static List<TreePojo> getRootNode(List treeList){
		List<TreePojo> rootList = new ArrayList<TreePojo>();
		for(int i = 0 ;i<treeList.size();i++){
			if(((TreePojo)treeList.get(i)).getPid()==0){
				rootList.add((TreePojo)treeList.get(i));
			}
		}
		return rootList;
	}

	//向新list中装入根节点并递归子节点
	public static List setRootNode(List treeList){
		List<TreePojo> rootNode = getRootNode(treeList);
		for(int i = 0 ;i<rootNode.size();i++){
			newList.add(rootNode.get(i));
			sortNode(rootNode.get(i),treeList);
		}
		
		return newList;
	}


	//递归子节点
	public static List<TreePojo> sortNode(TreePojo rootNode,List treeList){
		List<TreePojo> rightList=new ArrayList<TreePojo>();
		List<TreePojo> childList = getChild(rootNode,treeList);
		if(childList!=null){
			for(int i = 0;i<childList.size();i++){
				newList.add(childList.get(i));
				sortNode(childList.get(i),treeList);
			}
		}
		return childList;
	}
	
	
	//main方法调用
	public static void main(String[] args) {
		List treeList2=new ArrayList();
		treeList2.add(new TreePojo(7,5,"一级栏目1__子级2__子级1__"));
		treeList2.add(new TreePojo(1,0,"一级栏目1__"));
		treeList2.add(new TreePojo(2,0,"一级栏目2__"));
		treeList2.add(new TreePojo(3,1,"一级栏目1__子级1__"));
		treeList2.add(new TreePojo(4,0,"一级栏目3__"));
		treeList2.add(new TreePojo(5,1,"一级栏目1__子级2__"));
		treeList2.add(new TreePojo(6,1,"一级栏目1__子级3__"));
		treeList2.add(new TreePojo(8,0,"一级栏目4__"));
		treeList2.add(new TreePojo(9,2,"一级栏目2__子级1__"));
		
		List newList_=setRootNode(treeList2);
		
		//System.out.println(newList.size());
		for(int i=0;i < newList_.size();i++){
			TreePojo t=(TreePojo) newList_.get(i);
			System.out.println(t.getClassname());
		}
	}
}

/**
 * 
 * @author zyengogo
 *
 */
public class TreePojo {
	int treeid;
	int pid;
	String classname;
	
	public TreePojo() {
		
	}
	
	public TreePojo(int treeid,int pid,String classname) {
		this.treeid = treeid;
		this.pid = pid;
		this.classname = classname;
	}
	
	
	public int getTreeid() {
		return treeid;
	}
	public void setTreeid(int treeid) {
		this.treeid = treeid;
	}
	public int getPid() {
		return pid;
	}
	public void setPid(int pid) {
		this.pid = pid;
	}
	public String getClassname() {
		return classname;
	}
	public void setClassname(String classname) {
		this.classname = classname;
	}
}