computerdao.java

一个简单的struts,用于记录所有计算机的信息

package com.labosun.structs._56837;

import java.util.ArrayList;
import java.util.List;
import com.labosun.structs._56837.Computer;
public class ComputerDao {
		private static ComputerDao instance;
		private List<Computer> computerList;
		private int currentId;
		private ComputerDao() {
			computerList = new ArrayList<Computer>();
		}
		public static ComputerDao getDao(){
			if(instance==null)
				instance=new ComputerDao();
			return instance;
			
		}
		public void add(Computer c) {
			if(c!=null)
				c.setId(currentId++);
				computerList.add(c);
		}

		public void update(Computer c) {
			if(c!=null){
				Computer oldComputer = getComputerById(c.getId());
				int index = computerList.indexOf(oldComputer);
				computerList.set(index, c);
				computerList.remove(oldComputer);
			}
		}

		public Computer getComputerById(int id) {
			for (Computer c : computerList) {
				if (c.getId() == id) {
					return c;
				}
			}
			return null;
		}

		public void remove(Computer c) {
			if (c != null)
				computerList.remove(c);
		}

		public List<Computer> getAllComputer() {
			return computerList;
		}
	}