Flink--基于mysql的sink和source

基于mysql的source操作

object MysqlSource {
  def main(args: Array[String]): Unit = {
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    val source: DataStream[Student] = env.addSource(new SQL_source)
    source.print()
    env.execute()
  }
}
class SQL_source extends RichSourceFunction[Student]{
  private var connection: Connection = null
  private var ps: PreparedStatement = null

  override def open(parameters: Configuration): Unit = {
    val driver = "com.mysql.jdbc.Driver"
    val url = "jdbc:mysql://hadoop01:3306/test"
    val username = "root"
    val password = "root"
    Class.forName(driver)
    connection = DriverManager.getConnection(url, username, password)
    val sql = "select stuid , stuname , stuaddr , stusex from Student"
    ps = connection.prepareStatement(sql)
  }

  override def close(): Unit = {
    if(connection != null){
      connection.close()
    }
    if(ps != null){
      ps.close()
    }
  }

  override def run(sourceContext: SourceContext[Student]): Unit = {
    val queryRequest = ps.executeQuery()
    while (queryRequest.next()){
      val stuid = queryRequest.getInt("stuid")
      val stuname = queryRequest.getString("stuname")
      val stuaddr = queryRequest.getString("stuaddr")
      val stusex = queryRequest.getString("stusex")
      val stu = new Student(stuid , stuname , stuaddr , stusex)
      sourceContext.collect(stu)
    }
  }
  override def cancel(): Unit = {}
}

case class Student(stuid:Int , stuname:String , stuaddr:String , stusex:String){
  override def toString: String = {
    "stuid:"+stuid+"  stuname:"+stuname+"   stuaddr:"+stuaddr+"   stusex:"+stusex
  }
}

基于mysql的sink操作

object MysqlSink {
  def main(args: Array[String]): Unit = {
    //1.创建流执行环境
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    //2.准备数据
    val dataStream:DataStream[Student] = env.fromElements(
      Student(8, "xiaoming", "beijing biejing", "female")
//      Student(6, "daming", "tainjing tianjin", "male "),
//      Student(7, "daqiang ", "shanghai shanghai", "female")
    )

    //3.将数据写入到自定义的sink中（这里是mysql）
    dataStream.addSink(new StudentSinkToMysql)
    //4.触发流执行
    env.execute()
  }
}

class StudentSinkToMysql extends RichSinkFunction[Student]{
  private var connection:Connection = null
  private var ps:PreparedStatement = null

  override def open(parameters: Configuration): Unit = {
    val driver = "com.mysql.jdbc.Driver"
    val url = "jdbc:mysql://hadoop01:3306/test"
    val username = "root"
    val password = "root"
    //1:加载驱动
    Class.forName(driver)
    //2：创建连接
    connection = DriverManager.getConnection(url , username , password)
    val sql = "insert into Student(stuid , stuname , stuaddr , stusex) values(?,?,?,?);"
    //3:获得执行语句
    ps = connection.prepareStatement(sql)
  }

  //关闭连接操作
  override def close(): Unit = {
    if(connection != null){
      connection.close()
    }
    if(ps != null){
      ps.close()
    }
  }
  //每个元素的插入，都要触发一次invoke，这里主要进行invoke插入
  override def invoke(stu: Student): Unit = {
    try{
      //4.组装数据，执行插入操作
      ps.setInt(1, stu.stuid)
      ps.setString(2, stu.stuname)
      ps.setString(3, stu.stuaddr)
      ps.setString(4, stu.stusex)
      ps.executeUpdate()
    }catch {
      case e:Exception => println(e.getMessage)
    }
  }
}