treeservlet.java

组织结构树的实现

package com.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.model.TreeManager;
import com.vo.depVo;
public class TreeServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public TreeServlet() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doGet method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		//doPost(request, response);
		response.setCharacterEncoding("GB2312");
		request.setCharacterEncoding("GB2312");
		response.setContentType("text/html");
		TreeManager treeSql=new TreeManager();
		List tree=new ArrayList();
		tree=(ArrayList)treeSql.getAllNods();
		request.setAttribute("tree", tree);
		request.getRequestDispatcher("TransTree.jsp").forward(request, response);
	}


	
public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
	   doGet(request,response);
		response.setCharacterEncoding("GB2312");
		request.setCharacterEncoding("GB2312");
		response.setContentType("text/html");
		TreeManager treeSql=new TreeManager();
		List list=treeSql.getAllNods();
		printTree(response,list,new ArrayList(),0,0);
	}
	public void printTree(HttpServletResponse response,List list1,List list2,int pid,int n)throws ServletException, IOException 
	{//递归的另一种实现方式
		PrintWriter out=response.getWriter();
		for(int i=0;i<list1.size();i++){
			depVo vo=(depVo)list1.get(i);
			if(pid==vo.getPid()){
				pid=vo.getId();
				n=n+1;
				String tagStart="<B>";
				String tagEnd="</B>";
				if(n!=0){
					for(int k=0;k<n;k++){
						tagStart+="-";
						tagEnd="";
					}
					
				}
				out.println(tagStart+vo.getName()+tagEnd);
				list2.add(vo);
				list1.remove(i);
				printTree(response,list1,list2,pid,n);
			}
		} 
		if(n==-1){
			return;
		}else{
			if(list2!=null&&!list2.isEmpty()&&list2.size()!=0){
				pid=((depVo)list2.get(list2.size()-1)).getPid();
				list2.remove(list2.size()-1);
				n=n-1;
				printTree(response,list1,list2,pid,n);
			}
			
		}
		
	}

	
	public void init() throws ServletException {
		// Put your code here
	}

}