Flink 自定义 sink 写入 mysql

Flink写入mysql其实也很简单,只用继承RichSinkFunction这个类,重写里面的方法就行了.具体的实现如下:

/**
  * 把结果保存到mysql里面
  */
class MySQLSink extends RichSinkFunction[List[ItemViewCount]] with Serializable {
  var connection: sql.Connection = _
  var ps: sql.PreparedStatement = _
  var statement: java.sql.Statement = _
  val username = "***"
  val password = "***"
  val drivername = "com.mysql.jdbc.Driver"
  val url = "***"

  /**
    * 打开mysql的连接
    * @param parameters
    */
  override def open(parameters: Configuration): Unit = {
    Class.forName(drivername)
    connection = DriverManager.getConnection(url, username, password)
    statement = connection.createStatement
    connection.setAutoCommit(false)
  }

  /**
    * 处理数据后写入mysql
    * @param value
    */
  override def invoke(value: List[ItemViewCount]): Unit = {
    val sql = "insert into topn(itemid,viewcount)