import com.mysql.jdbc.Connection;
import entity.User;
import org.junit.Test;
import redis.clients.jedis.Jedis;

import java.sql.*;
import java.util.LinkedList;

/**
 * @描述  佇列解決高併發，redis,快取與資料庫不一致問題
 * @引數 $
 * @返回值 $
 * @建立人 [email protected]
 * @建立時間 $
 * @修改人和其它資訊
 */



public class TestQueueSolution {


    //獲得mysqlconnection
    public Connection getMysqlConn() {
        String driver = "com.mysql.jdbc.Driver";
        String url = "jdbc:mysql://localhost:3306/redistest?useSSL=false";
        String username = "root";
        String password = "root";
        Connection conn = null;
        try {
            Class.forName(driver); //classLoader,載入對應驅動
            conn = (Connection) DriverManager.getConnection(url, username, password);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
        return conn;
    }

    public User execQuerySql(Connection connection,String sqlStr, LinkedList parms) throws SQLException {
        PreparedStatement pstmt = null;
        ResultSet resultSet = null;
        pstmt = connection.prepareStatement(sqlStr);
        for (int i = 1 ; i <= parms.size() ; i++ ){
            ///記得 後面跟的是 i-1
            pstmt.setObject(i,parms.get(i-1));
        }
        resultSet = pstmt.executeQuery();
        User user = null;
        while (resultSet.next()){
            user = new User();
            System.out.println("----------------");
            user.setId(resultSet.getInt("id"));
            user.setAge(resultSet.getInt("age"));
            user.setBirthday(resultSet.getDate("birthday"));
            user.setName(resultSet.getString("name"));
        }
        return user;

    }


    //執行sql 以及引數
    public Integer exeuUpdateTheSqlWithParms(Connection connection,String sql,LinkedList parms) throws SQLException {
        PreparedStatement pstmt = null;
        ResultSet resultSet = null;
        pstmt = connection.prepareStatement(sql);
        //設定引數
        for (int i = 1 ; i <= parms.size(); i++){
            pstmt.setObject(i,parms.get(i-1));
        }
        Integer count = pstmt.executeUpdate();
        return  count;
    }



        //刪除redis並延遲更新資料的執行緒
        class UpdateRedisDataBaseThread implements Runnable{
            public String redisKey;
             //每個執行緒獲取自己的connection
            public Connection connection;
            //資料庫 名字
            public String parmName;
            //設定資料年齡
            public Integer age;

            public UpdateRedisDataBaseThread(String redisKey, String parmName, Integer age) {
                this.redisKey = redisKey;
                this.parmName = parmName;
                this.age = age;
            }

            @Override
            public void run() {
                //每個執行緒自己 的 redis 客戶端
                Jedis jedis  =  new Jedis("127.0.0.1",6379);
                //如果存在則進行刪除
                if ( jedis.exists(this.redisKey) ){
                    System.out.println("del a value from redis :" + this.redisKey);
                    jedis.del(this.redisKey);
                }
                //模擬延遲更新資料庫
                //設定引數
                this.connection = getMysqlConn();
                String sqlStr = "update t_user set age = ? where name = ?";
                LinkedList parm_link = new LinkedList();
                parm_link.add(age);
                parm_link.add(parmName);
                try {
                    //休眠一秒
                    System.out.println("UpdateRedisDataBaseThread sleep 3s");
                    Thread.sleep(3000);
                    Integer count  =   exeuUpdateTheSqlWithParms(connection,sqlStr,parm_link);
                    System.out.println("UpdateRedisDataBaseThread update database count:"+count);

                } catch (SQLException e) {
                    e.printStackTrace();
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }

        //直接更改資料庫的執行緒
        class SelectThread implements  Runnable{
            //每個執行緒獲取自己的connection
            public Connection connection;
            //查詢引數
            public String parmName;
            //查詢結果
            public String queryResult;

            public SelectThread(String parmName) {
                this.parmName = parmName;
            }

            @Override
            public void run() {
                //每個執行緒自己 的 redis 客戶端
                Jedis jedis  =  new Jedis("127.0.0.1",6379);
                //如果redis存在則直接得到值
                if (jedis.exists(parmName)){
                    System.out.println("SelectThread can not get value parm:" + this.parmName);
                    this.queryResult = jedis.get(parmName);
                }else {
                    //快取沒有則到資料庫查詢
                    this.connection = getMysqlConn();
                    String sqlStr = "select * from t_user where name = ?";
                    LinkedList parm_link = new LinkedList();
                    parm_link.add(parmName);
                    try {
                        User user  =   execQuerySql(connection,sqlStr,parm_link);
                        if ( user != null ){
                            this.queryResult  = user.toString();
                            //--將結果寫到redis
                            System.out.println(Thread.class.getName()+" parm " + this.parmName  +" set a vlaue to redis!");
                            jedis.set(this.parmName,this.queryResult);
                        }

                    } catch (SQLException e) {
                        e.printStackTrace();
                    }
                }
            }

        }



        @Test
        public void test() throws InterruptedException {
            //衝突的記錄
            String cfkName = "liming01";
            //第一條請求-執行更新操作的執行緒
            UpdateRedisDataBaseThread drud = new UpdateRedisDataBaseThread(cfkName,"liming01",66);
            //併發第二條請求 - 執行查詢操作的執行緒
            SelectThread udbt = new SelectThread(cfkName);
            new Thread(drud).start();
            //休眠一秒-模擬其它操作
            Thread.sleep(2000);
            //第二個執行緒開始查詢
            new Thread(udbt).start();
            //主執行緒休眠10s
            Thread.sleep(10000);//休眠20s

        }



}