java中实现无限层级的树形结构

数据库设计

java代码

实体类

public class Tree {
	private int id;
	private String name;
	private int pid;
	private List<Tree> childList;
}


///controller 中调用方法
List<Tree> listAll =  数据中查所有
int pid = 0;
List<Tree> listResult = getNode(listAll,pid);

private List<Tree> getNode(List<Tree> selectTree, int pid){
	List<Tree> tempList = getTempList(selectTree,pid):
	if(tempList.size() > 0){
		for(int i=0; i<tempList.size(); i++){
			tempList.setChildList(getNode(selectTree,tempList.get(i).getId()));
		}
	}
	return tempList;
}

private List<Tree> getTempList(List<Tree> selectTree, int pid){
	List<Tree> tempList = new ArrayList<Tree>();
	for(int i=0; i<selectTree; i++){
		if(selectTree.get(i).getPid == pid){
			tempList.add(selectTree.get(i));
		}
	}
	return tempList ;
}