項目框架結構
Properties
db.properties:
db.username=root
db.password=root
db.url=jdbc:mysql://192.168.77.14/test
log4j.properties:
# DEBUG\u8BBE\u7F6E\u8F93\u51FA\u65E5\u5FD7\u7EA7\u522B\uFF0C\u7531\u4E8E\u4E3ADEBUG\uFF0C\u6240\u4EE5ERROR\u3001WARN\u548CINFO \u7EA7\u522B\u65E5\u5FD7\u4FE1\u606F\u4E5F\u4F1A\u663E\u793A\u51FA\u6765
log4j.rootLogger=DEBUG,Console,RollingFile
#\u5C06\u65E5\u5FD7\u4FE1\u606F\u8F93\u51FA\u5230\u63A7\u5236\u53F0
log4j.appender.Console=org.apache.log4j.ConsoleAppender
log4j.appender.Console.layout=org.apache.log4j.PatternLayout
log4j.appender.Console.layout.ConversionPattern= [%-5p]-[%d{yyyy-MM-dd HH:mm:ss}] -%l -%m%n
#\u5C06\u65E5\u5FD7\u4FE1\u606F\u8F93\u51FA\u5230\u64CD\u4F5C\u7CFB\u7EDFD\u76D8\u6839\u76EE\u5F55\u4E0B\u7684log.log\u6587\u4EF6\u4E2D
log4j.appender.RollingFile=org.apache.log4j.DailyRollingFileAppender
log4j.appender.RollingFile.File=E://log.log
log4j.appender.RollingFile.layout=org.apache.log4j.PatternLayout
log4j.appender.RollingFile.layout.ConversionPattern=%d [%t] %-5p %-40.40c %X{traceId}-%m%n
工具類
MD5Tool:
package com.jd.tool;
import java.math.BigInteger;
import java.security.MessageDigest;
public class MD5Tool {
public static String encrypt(String password) {
byte[] bytes = null;
try {
MessageDigest messageDigest = MessageDigest.getInstance("MD5");
messageDigest.update(password.getBytes());//加密
bytes = messageDigest.digest();//獲得加密結果
} catch (Exception e) {
e.printStackTrace();
}
String result = new BigInteger(1, bytes).toString(16);// 將加密後的數據轉換爲16進制數字
// 生成數字未滿32位,則前面補0
for (int i = 0; i < 32 - result.length(); i++) {
result = "0" + result;
}
return result;
}
}
PropertiesTool:
package com.jd.tool;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
public class PropertiesTool {
private static Properties properties = new Properties();
static {
InputStream inputStream = PropertiesTool.class.getClassLoader().getResourceAsStream("db.properties");//將db.properties變爲javaIO流對象
try {
properties.load(inputStream);
} catch (IOException e) {
e.printStackTrace();
}
}
public static String getValue(String key) {
String value = properties.getProperty(key);
return value;
}
}
dbLink:
package com.jd.tool.db;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.apache.log4j.Logger;
import com.jd.tool.PropertiesTool;
/**
* 數據庫工具類
*
* @author Administrator
*/
public class DBLink {
private Logger logger = Logger.getLogger(DBLink.class);
/**
* 獲取數據庫鏈接
* @return
*/
private Connection getConnection() {
try {
Class.forName("com.mysql.jdbc.Driver");//加載驅動
String userName = PropertiesTool.getValue("db.username");
String passWord = PropertiesTool.getValue("db.password");
String url = PropertiesTool.getValue("db.url");
return DriverManager.getConnection(url ,userName,passWord);
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}
return null;
}
/**
* 判斷sql語句是否存在數據
* @param sql
* @return
*/
public boolean exist(String sql) {
Connection connection = null;
Statement statement = null;
ResultSet resultSet = null;
try {
connection = getConnection();
statement = connection.createStatement();
resultSet = statement.executeQuery(sql);
return resultSet.next();
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(resultSet, statement, connection);
}
return false;
}
public boolean exist(String sql,Object ...params) {
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
try {
connection = getConnection();
preparedStatement = connection.prepareStatement(sql);
for (int i = 0; i < params.length; i++) {
preparedStatement.setObject(i+1, params[i]);
}
resultSet = preparedStatement.executeQuery();
return resultSet.next();
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(resultSet, preparedStatement, connection);
}
return false;
}
/**
* 查詢數據
* @param sql
* @param rowMapper
*/
public void select(String sql, IRowMapper rowMapper) {//接口無法創建對象,所以rowMapper參數一定指向IRowMapper接口實現類對象
Connection connection = null;
Statement statement = null;
ResultSet resultSet = null;
try {
connection = getConnection();
statement = connection.createStatement();
resultSet = statement.executeQuery(sql);
rowMapper.rowMapper(resultSet);
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(resultSet, statement, connection);
}
}
/**
* 查詢數據
* @param sql
* @param rowMapper
*/
public void select(String sql, IRowMapper rowMapper,Object ...params) {//接口無法創建對象,所以rowMapper參數一定指向IRowMapper接口實現類對象
Connection connection = null;
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
try {
connection = getConnection();
preparedStatement = connection.prepareStatement(sql);//含有?佔位符的sql
for (int i = 0; i < params.length; i++) {
preparedStatement.setObject(i + 1, params[i]);//爲?賦值
}
resultSet = preparedStatement.executeQuery();//執行sql
rowMapper.rowMapper(resultSet);
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(resultSet, preparedStatement, connection);
}
}
/**
* 修改(insert、update、delete)數據
* @param sql
* @return
*/
public boolean update(String sql) {
Connection connection = null;
Statement statement = null;
try {
connection = getConnection();
System.out.println(connection);
statement = connection.createStatement();//獲取statement對象
int result = statement.executeUpdate(sql);//執行sql語句,返回受影響的行數
return result>0;
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(statement, connection);
}
return false;
}
/**
* 修改(insert、update、delete)數據
* @param sql
* @return
*/
public boolean update(String sql,Object ...params) {
Connection connection = null;
PreparedStatement prepareStatement = null;
try {
connection = getConnection();
prepareStatement = connection.prepareStatement(sql);
for (int i = 0; i < params.length; i++) {
prepareStatement.setObject(i+1, params[i]);//爲?賦值
}
return prepareStatement.executeUpdate()>0;
} catch (Exception e) {
logger.debug(e.getMessage(), e);
}finally {
close(prepareStatement, connection);
}
return false;
}
/**
* 釋放資源
* @param statement
* @param connection
*/
private void close(Statement statement,Connection connection) {
try {
if(statement!=null) {
statement.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(), e);
}
try {
if(connection!=null) {
connection.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(), e);
}
}
/**
* 釋放資源
* @param statement
* @param connection
*/
private void close(ResultSet resultSet,Statement statement,Connection connection) {
try {
if(resultSet!=null) {
resultSet.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(), e);
}
try {
if(statement!=null) {
statement.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(), e);
}
try {
if(connection!=null) {
connection.close();
}
} catch (SQLException e) {
logger.debug(e.getMessage(), e);;
}
}
}
IRowMapper:
package com.jd.tool.db;
import java.sql.ResultSet;
public interface IRowMapper {
void rowMapper(ResultSet rs);
}
程序主體
Main:
package com.jd.test;
import java.util.Scanner;
import java.util.UUID;
import com.jd.tool.MD5Tool;
import com.jd.tool.db.DBLink;
public class Main {
private static DBLink db = new DBLink();
public static void main(String[] args) {
System.out.println("*********************************");
System.out.println("*\t\t\t\t*");
System.out.println("*\t歡迎使用註冊登錄系統\t\t*");
System.out.println("*\t\t\t\t*");
System.out.println("*********************************");
while (true) {
menu();
}
}
public static void menu() {
System.out.println("1、註冊");//用戶名 密碼 確認密碼
System.out.println("2、登錄");//用戶名和密碼
System.out.println("3、退出");//System.exit(0);
System.out.println("請輸入操作,以Enter鍵結束:");
Scanner scanner = new Scanner(System.in);
int option = scanner.nextInt();
switch (option) {
case 1:{
String name = null;
String password = null;
String rePassword = null;
String id = null;
String sql = null;
System.out.println("請輸入用戶名:");
name = scanner.next();
sql = "select id from user_info where user_name=?";
if(db.exist(sql,name)) {
System.out.println("用戶名已經存在,註冊失敗");
return;
}
System.out.println("請輸入密碼:");
password = scanner.next();
System.out.println("請輸入確認密碼");
rePassword = scanner.next();
if(!password.equals(rePassword)) {
System.out.println("兩次輸入密碼不一致,註冊失敗");
return;
}
id = UUID.randomUUID().toString();
password = MD5Tool.encrypt(password);//進行加密後再儲存到數據庫中
sql="insert into user_info (id,user_name,password) values ('"+id+"',?,?)";
if(db.update(sql,name,password)) {
System.out.println("註冊成功!");
return;
}
System.out.println("註冊失敗!");
break;
}
case 2:{
String name = null;
String password = null;
String sql = null;
System.out.println("請輸入用戶名:");
name = scanner.next();
System.out.println("請輸入密碼:");
password = scanner.next();
password = MD5Tool.encrypt(password);
sql = "select id from user_info where user_name=? and password=?";
if(db.exist(sql,name,password)) {
System.out.println("登陸成功!");
return;
}
System.out.println("登陸失敗!");
break;
}
case 3:{
System.out.println("已退出系統");
System.exit(0);
break;
}
default:
System.out.println("I'm Sorry,there is not the "+option+" option,please try again.");
}
}
}