import java.sql.{Connection, PreparedStatement}
import java.util.Properties

import com.alibaba.druid.pool.DruidDataSourceFactory
import javax.sql.DataSource

object JDBCUtil {
  // 初始化连接池
  var dataSource: DataSource = init()

  def init(): DataSource = {
    val properties: Properties = new Properties()
    properties.setProperty("driverClassName", "com.mysql.jdbc.Driver")
    properties.setProperty("url", "jdbc:mysql://localhost:3306/chapter05")
    properties.setProperty("username", "root")
    properties.setProperty("password", "123456")
    properties.setProperty("maxActive", "50")
    DruidDataSourceFactory.createDataSource(properties)
  }

  // 获取 MySQL 连接
  def getConnection: Connection = {
    dataSource.getConnection() 
  }

  // 执行 SQL 语句，单挑数据插入
  def executeUpdate(connection: Connection, sql: String, params: Array[Any]): Int = {
    var rtn = 0
    var pstmt: PreparedStatement = null
    try {
      connection.setAutoCommit(false)
      pstmt = connection.prepareStatement(sql)

      if (params != null && params.length > 0) {
        for (i <- params.indices) {
          pstmt.setObject(i+1, params(i))
        }
      }
      rtn = pstmt.executeUpdate()
      connection.commit()
      pstmt.close()
    } catch  {
      case e: Exception => e.printStackTrace()
    }
    rtn
  }

  // 判断一条数据是否存在
  def isExist(connection: Connection, sql: String, params: Array[Any]): Boolean = {
    var flag: Boolean = false
    var pstmt: PreparedStatement = null
    try {
      pstmt = connection.prepareStatement(sql)
      for (i <- params.indices) {
        pstmt.setObject(i+1, params(i))
      }
      flag = pstmt.executeQuery().next()
      pstmt.close()
    } catch {
      case e: Exception => e.printStackTrace()
    }
    flag
  }
}