import java.util.ArrayList;
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import java.util.List;
import java.util.Scanner;
/**
*
* @author young
*
*/
class User{
private String no;
private String name;
private int age;
private String add;
public String getNo() {
return no;
}
public void setNo(String no) {
this.no = no;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getAdd() {
return add;
}
public void setAdd(String add) {
this.add = add;
}
}
public class Test {
// 增加
public static ArrayListUser addUser(){
ListUser list = new ArrayListUser();
User u = new User();
Scanner sc = new Scanner(System.in);
System.out.print("输入 no: ");
u.setNo(sc.nextLine());
System.out.print("输入name: ");
u.setName(sc.nextLine());
System.out.print("输入add: ");
u.setAdd(sc.nextLine());
System.out.print("输入age: ");
u.setAge(sc.nextInt());
list.add(u);
return (ArrayListUser) list;
}
// 修改
public static void updateUser(String name, ListUser list){
Scanner sc = new Scanner(System.in);
boolean isExist = false;
for(int i = 0; i list.size(); i++){
if(name.equals(list.get(i).getName())){
isExist = true;
System.out.print("输入新 no: ");
list.get(i).setNo(sc.nextLine());
System.out.print("输入新name: ");
list.get(i).setName(sc.nextLine());
System.out.print("输入新add: ");
list.get(i).setAdd(sc.nextLine());
System.out.print("输入新age: ");
list.get(i).setAge(sc.nextInt());
}
}
if(isExist == false){
System.out.println("不存在该用户");
}
}
// 查找
public static void findUser(String name, ListUser list){
boolean isExist = false;
for(int i = 0; i list.size(); i++){
if(name.equals(list.get(i).getName())){
isExist = true;
System.out.println("用户编号: " + list.get(i).getNo()
+ ". 姓名: " + list.get(i).getName()
+ ". 地址: " + list.get(i).getAdd()
+ ". 年龄: " + list.get(i).getAge());
}
}
if(isExist == false){
System.out.println("不存在该用户");
}
}
// 删除
public static void delUser(String name, ListUser list) {
boolean isExist = false;
for (int i = 0; i list.size(); i++) {
if (name.equals(list.get(i).getName())) {
isExist = true;
list.remove(i);
System.out.println("该用户已删除");
}
}
if (isExist == false) {
System.out.println("不存在该用户");
}
}
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
ListUser list = new ArrayListUser();
int i = 0;
while(true){
System.out.println("输入你的选择: 1.增加\t2.查找\t3.修改\t4.删除\t0.退出");
i = sc.nextInt();
switch (i) {
case 1:
list = addUser();
break;
case 2:
System.out.print("输入要查找的用户名: ");
String name = sc.next();
findUser(name, list);
break;
case 3:
System.out.print("输入要修改的用户名: ");
String n = sc.next();
updateUser(n, list);
break;
case 4:
System.out.print("输入要删除的用户名: ");
String na = sc.next();
delUser(na, list);
break;
case 0:
System.out.println("程序结束!");
System.exit(0);
break;
}
}
}
}
展开全部
类似于下面那样连接数据库：
package com.bjsxt.drp.util;
import java.sql.*;
public class DB {
public static Connection getConn() {
Connection conn = null;
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/drp?user=rootpassword=root");
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
}
public static Statement getStatement(Connection conn) {
Statement stmt = null;
try {
if(conn != null) {
stmt = conn.createStatement();
}
} catch (SQLException e) {
e.printStackTrace();
}
return stmt;
}
public static ResultSet getResultSet(Statement stmt, String sql) {
ResultSet rs = null;
try {
if(stmt != null) {
rs = stmt.executeQuery(sql);
}
} catch (SQLException e) {
e.printStackTrace();
}
return rs;
}
public static void closeConn(Connection conn) {
try {
if(conn != null) {
conn.close();
conn = null;
}
} catch (SQLException e) {
e.printStackTrace();
}
}
public static void closeStmt(Statement stmt) {
try {
if(stmt != null) {
stmt.close();
stmt = null;
}
} catch (SQLException e) {
e.printStackTrace();
}
}
public static void closeRs(ResultSet rs) {
try {
if(rs != null) {
rs.close();
rs = null;
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}
下面是个用户Bean：
package com.bjsxt.drp.sysmgr;
import java.util.Date;
/**
* 用户实体类
* @author Administrator
*
*/
public class User {
//用户代码
private String userId;
//用户名称
private String userName;
//密码
private String password;
//联系电话
private String contactTel;
private String email;
//创建日期
private Date createDate;
public String getContactTel() {
return contactTel;
}
public void setContactTel(String contactTel) {
this.contactTel = contactTel;
}
public Date getCreateDate() {
return createDate;
}
public void setCreateDate(Date createDate) {
this.createDate = createDate;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getUserId() {
return userId;
}
public void setUserId(String userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
}
下面是一个用户管理类来对用户进行增删改查：
package com.bjsxt.drp.sysmgr;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.List;
import com.bjsxt.drp.util.DB;
import com.bjsxt.drp.util.PageModel;
/**
* 对用户完成增删改查的类
* @author Administrator
*
*/
public class UserManager {
// private static UserManager instance;
//
// private UserManager() {
//
// }
//
// public static synchronized UserManager getInstance() {
// if (instance == null) {
// instance = new UserManager();
// }
// return instance;
// }
private static UserManager instance = new UserManager();
private UserManager() {
}
public static UserManager getInstance() {
return instance;
}
/**
* 增加用户
* @param user user用户对象
*/
public void addUser(User user) {
String sql ="insert into t_user(user_id, user_name, password, contact_tel, email, create_date) " +
"values(?, ?, ?, ?, ?, ?)";
Connection conn = null;
PreparedStatement pstmt = null;
try {
conn = DB.getConn();
pstmt = conn.prepareStatement(sql);
pstmt.setString(1, user.getUserId());
pstmt.setString(2, user.getUserName());
pstmt.setString(3, user.getPassword());
pstmt.setString(4, user.getContactTel());
pstmt.setString(5, user.getEmail());
pstmt.setTimestamp(6, new Timestamp(user.getCreateDate().getTime()));
pstmt.executeUpdate();
}catch(SQLException e) {
e.printStackTrace();
}finally {
DB.closeStmt(pstmt);
DB.closeConn(conn);
}
}
/**
* 根据用户代码查询
* @param userId 用户代码
* @return user对象
*/
public User findUserById(String userId) {
String sql = "select * from t_user where user_id=?";
System.out.println("findUserById()==sql=" + sql);
User user = null;
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try {
conn = DB.getConn();
pstmt = conn.prepareStatement(sql);
pstmt.setString(1, userId);
rs = pstmt.executeQuery();
if (rs.next()) {
user = new User();
user.setUserId(rs.getString("user_id"));
user.setUserName(rs.getString("user_name"));
user.setPassword(rs.getString("password"));
user.setContactTel(rs.getString("contact_tel"));
user.setEmail(rs.getString("email"));
user.setCreateDate(rs.getTimestamp("create_date"));
}
}catch(SQLException e) {
e.printStackTrace();
}finally {
DB.closeRs(rs);
DB.closeStmt(pstmt);
DB.closeConn(conn);
}
return user;
}
/**
* 分页查询所有的用户数据
* @param pageNo 第几页
* @param pageSize 每页显示多少条
* @return pageModel对象
*/
public PageModel findAllUser(int pageNo, int pageSize) {
PageModel pageModel = null;
String sql ="select * from t_user where user_id 'root' order by user_id " +
"limit " + (pageNo - 1) * pageSize + ", " + pageSize;
Connection conn = null;
Statement stmt = null;
ResultSet rs = null;
try {
conn = DB.getConn();
stmt = conn.createStatement();
rs = stmt.executeQuery(sql);
List userList = new ArrayList();
while (rs.next()) {
User user = new User();
user.setUserId(rs.getString("user_id"));
user.setUserName(rs.getString("user_name"));
user.setPassword(rs.getString("password"));
user.setContactTel(rs.getString("contact_tel"));
user.setEmail(rs.getString("email"));
user.setCreateDate(rs.getTimestamp("create_date"));
userList.add(user);
}
int totalRecords = getTotalRecords(conn);
pageModel = new PageModel();
pageModel.setPageNo(pageNo);
pageModel.setPageSize(pageSize);
pageModel.setTotalRecords(totalRecords);
pageModel.setList(userList);
}catch(SQLException e) {
e.printStackTrace();
}finally {
DB.closeRs(rs);
DB.closeStmt(stmt);
DB.closeConn(conn);
}
return pageModel;
}
/**
* 返回所有的用户数
* @param conn
* @return 记录数
*/
private int getTotalRecords(Connection conn) {
String sql = "select count(*) from t_user where user_id 'root'";
int totalRecords = 0;
Statement stmt = null;
ResultSet rs = null;
try {
stmt = conn.createStatement();
rs = stmt.executeQuery(sql);
if (rs.next()) {
totalRecords = rs.getInt(1);
}
}catch(SQLException e) {
e.printStackTrace();
}finally {
DB.closeRs(rs);
DB.closeStmt(stmt);
}
return totalRecords;
}
/**
* 根据用户ID删除用户
* @param userId userId
*/
public void deleteUserById(String userId) {
String sql = "delete from t_user where user_id=?";
Connection conn = null;
PreparedStatement pstmt = null;
try {
conn = DB.getConn();
pstmt = conn.prepareStatement(sql);
pstmt.setString(1, userId);
pstmt.executeUpdate();
}catch(SQLException e) {
e.printStackTrace();
}finally {
DB.closeStmt(pstmt);
DB.closeConn(conn);
}
}
/**
* 根据UserId的集合进行删除
* @param userIds userId的集合
*
* 可以把jsp中的userId数组传过来，形成如下SQL：
* delete from t_user where user_id in ('a0001', 'a0002')
*/
public void deleteUserByIds(String[] userIds) {
}
}
1. 用户信息管理一般包括：用户创建、用户修改、用户删除、用户查询四大块功能。
2. 定义基本实体类：User，包含name, address, idNum,tel,regTime四个属性和相应get/set方法。
3. 定义好后台数据库中的用户表user_T
4. 编写对用户进行增/删/改/查操作的数据库访问层代码
5. 编写对用户进行增/删/改/查操作前台页面，调用相应的后台方法即可。
具体代码？呵呵，有点太麻烦。先给点分再说吧。
