javamap代码 javamap详解( 二 )


main.java
package baidu.zhidao;
import java.util.*;
/**
* Main 主方法
* @author bufei
*
*/
public class Main {
public static void main(String[] args) {
int userNum = 9;
// 定义UserList
ListUser list = new ArrayListUser();
for (int i = 0; iuserNum; i++) {
User user = new User();
user.setPassWord("passWord" + i);
user.setUserName("userName" + i);
list.add(user);
}
// 实例化UserImpl
UserImpl userImpl = new UserImpl(list);
// 用户 张三 是否存在
String userName = "张三";
String passWord = "passWord";
User user = new User();
user.setUserName(userName);
user.setPassWord(passWord);
System.out.println("- - - baiduDemo - - -");
// 1、isExist(user)
System.out.println("查找用户 " + userName + "...");
if (userImpl.isExist(user)) {
System.out.println(userName + " 存在!");
} else {
System.out.println(userName + " 不存在!");
}
// 2、addUser
System.out.println("添加用户 " + userName + ",psw= " + passWord + " ...");
userImpl.addUser(user);
// 3、changePassword(userName)
System.out.println("修改密码...");
passWord = "zhangsanpasword";
if (userImpl.changePassword(userName, passWord)) {
System.out.println("修改成功!");
} else {
System.out.println("用户不存在!");
}
//4 selectAll()
list = userImpl.selectAll();
System.out.println("获取全部User:");
for (User userItem : list) {
System.out.println(userItem.getUserName() + "," + userItem.getPassWord());
}
}
}
UserImpl.java
package baidu.zhidao;
import java.util.*;
/**
* UserDao接口实现
* @author bufei
*
*/
public class UserImpl implements UserDao {
private MapDal mapDal;
/**
* 构造器,初始化Map数据库
*/
public UserImpl(ListUser list) {
【javamap代码 javamap详解】mapDal = new MapDal(list);
}
/**
* 1.判断某个user是否存在
* @param user 用户对象
* @return 返回true/false用户是否存在
*/
public boolean isExist(User user) {
boolean rs = false;
rs = mapDal.isExist(user);
return rs;
}
/**
* 2.添加User
* 题目所给void 返回类型不合理
* @param user
*
* */
public void addUser(User user) {
if (mapDal.addUser(user)) {
System.out.println("添加完成!");
} else {
System.out.println("添加失败!");
}
}
/**
* 3.根据username修改password
* @param username
* @param password
* @return 成功与否
* */
public boolean changePassword(String userName, String password) {
boolean rs = false;
User user = new User();
user.setUserName(userName);
user.setPassWord(password);
rs = mapDal.changePassword(user);
return rs;
}
/**
* 根据用户对象修改密码
* @param user
* @return
*/
public boolean changePassword(User user) {
return mapDal.changePassword(user);
}
/**
* 4.得到所有的User,用List封装
* @return 从数据库查询到所有的User
* */
public ListUser selectAll() {
return mapDal.selectAll();
}
}
MapDal.java
package baidu.zhidao;
import java.util.*;
/**
* MapDml 用map模拟数据库,初始化生成一些User
* 单例模式,避免数据不同步
* @author bufei
*
*/
public class MapDal {
/** list中存map,实在绕得很,直接存User也是可以 */
public static ListMapString, String userMapList = new ArrayListMapString, String();
/**
* 初始化,有参构造器

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