Stream Environment and Execution

object StreamExecutionEnvironment {
  def getExecutionEnvironment: StreamExecutionEnvironment
  def createLocalEnvironment(): StreamExecutionEnvironment
  def createLocalEnvironment(parallelism: Int): StreamExecutionEnvironment
  def createLocalEnvironmentWithWebUI(config: Configuration): StreamExecutionEnvironment
  def createRemoteEnvironment(host: String, port: Int, jarFiles: String*): StreamExecutionEnvironment
  def setDefaultLocalParallelism(parallelism: Int): Unit
  def getDefaultLocalParallelism: Int
}

import org.apache.flink.streaming.api.scala._

// Get context-appropriate environment (local or cluster)
val env = StreamExecutionEnvironment.getExecutionEnvironment

// Create local environment with specific parallelism
val localEnv = StreamExecutionEnvironment.createLocalEnvironment(4)

// Create remote cluster environment
val remoteEnv = StreamExecutionEnvironment.createRemoteEnvironment(
  "localhost", 8081, "/path/to/your-program.jar"
)

class StreamExecutionEnvironment {
  def setParallelism(parallelism: Int): Unit
  def getParallelism: Int
  def setMaxParallelism(maxParallelism: Int): Unit
  def getMaxParallelism: Int
}

class StreamExecutionEnvironment {
  def setBufferTimeout(timeoutMillis: Long): Unit
  def getBufferTimeout: Long
  def disableOperatorChaining(): Unit
}

class StreamExecutionEnvironment {
  def setStreamTimeCharacteristic(characteristic: TimeCharacteristic): Unit
  def getStreamTimeCharacteristic: TimeCharacteristic
}

val env = StreamExecutionEnvironment.getExecutionEnvironment

// Set parallelism for all operators
env.setParallelism(4)

// Set buffer timeout for low-latency processing
env.setBufferTimeout(0)  // Flush after every record

// Configure time characteristic for event time processing
env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime)

class StreamExecutionEnvironment {
  def enableCheckpointing(interval: Long): Unit
  def enableCheckpointing(interval: Long, mode: CheckpointingMode): Unit
  def enableCheckpointing(interval: Long, mode: CheckpointingMode, force: Boolean): Unit
  def getCheckpointConfig: CheckpointConfig
  def getCheckpointingMode: CheckpointingMode
}

class StreamExecutionEnvironment {
  def setStateBackend(backend: AbstractStateBackend): Unit
  def getStateBackend: AbstractStateBackend
}

class StreamExecutionEnvironment {
  def setRestartStrategy(restartStrategyConfiguration: RestartStrategyConfiguration): Unit
  def getRestartStrategy: RestartStrategyConfiguration
  def setNumberOfExecutionRetries(numRetries: Int): Unit  // Deprecated
  def getNumberOfExecutionRetries: Int  // Deprecated
}

import org.apache.flink.streaming.api.CheckpointingMode
import org.apache.flink.api.common.restartstrategy.RestartStrategies
import org.apache.flink.runtime.state.filesystem.FsStateBackend

val env = StreamExecutionEnvironment.getExecutionEnvironment

// Enable checkpointing every 5 seconds with exactly-once mode
env.enableCheckpointing(5000, CheckpointingMode.EXACTLY_ONCE)

// Configure checkpoint settings
val checkpointConfig = env.getCheckpointConfig
checkpointConfig.setCheckpointTimeout(60000)  // 1 minute timeout
checkpointConfig.setMaxConcurrentCheckpoints(1)
checkpointConfig.setMinPauseBetweenCheckpoints(500)

// Set filesystem state backend
env.setStateBackend(new FsStateBackend("hdfs://namenode:port/flink-checkpoints"))

// Configure restart strategy
env.setRestartStrategy(RestartStrategies.fixedDelayRestart(3, 10000))  // 3 attempts, 10s delay

class StreamExecutionEnvironment {
  def addDefaultKryoSerializer[T](type: Class[_], serializer: T): Unit
  def addDefaultKryoSerializer(type: Class[_], serializerClass: Class[_]): Unit
  def registerTypeWithKryoSerializer[T](clazz: Class[_], serializer: T): Unit
  def registerTypeWithKryoSerializer(clazz: Class[_], serializer: Class[_]): Unit
  def registerType(typeClass: Class[_]): Unit
}

import com.esotericsoftware.kryo.Serializer

val env = StreamExecutionEnvironment.getExecutionEnvironment

// Register custom type for better serialization performance
env.registerType(classOf[MyCustomClass])

// Register custom Kryo serializer
env.registerTypeWithKryoSerializer(classOf[MyClass], classOf[MyClassSerializer])

class StreamExecutionEnvironment {
  def registerCachedFile(filePath: String, name: String): Unit
  def registerCachedFile(filePath: String, name: String, executable: Boolean): Unit
  def getCachedFiles: java.util.Set[java.util.Map.Entry[String, DistributedCache.DistributedCacheEntry]]
}

val env = StreamExecutionEnvironment.getExecutionEnvironment

// Register a data file in distributed cache
env.registerCachedFile("/path/to/lookup-data.txt", "lookup-data")

// Register an executable file
env.registerCachedFile("/path/to/external-tool", "tool", executable = true)

class StreamExecutionEnvironment {
  def execute(): JobExecutionResult
  def execute(jobName: String): JobExecutionResult
  def getExecutionPlan: String
  def getStreamGraph: StreamGraph
}

val env = StreamExecutionEnvironment.getExecutionEnvironment

// Create your streaming program
val stream = env.fromElements(1, 2, 3, 4, 5)
  .map(_ * 2)
  .print()

// Execute the program
env.execute("My Streaming Job")

// Get execution plan as JSON (for debugging)
val executionPlan = env.getExecutionPlan
println(executionPlan)

class StreamExecutionEnvironment {
  def getConfig: ExecutionConfig
  def getJavaEnv: org.apache.flink.streaming.api.environment.StreamExecutionEnvironment
}

val env = StreamExecutionEnvironment.getExecutionEnvironment
val config = env.getConfig

// Configure global job parameters
config.setGlobalJobParameters(new MyJobParameters())

// Configure auto-generated UIDs
config.setAutoGeneratedUidsEnabled(false)

// Configure serialization
config.enableForceKryo()
config.enableGenericTypes()

import org.apache.flink.streaming.api.scala._
import org.apache.flink.streaming.api.{CheckpointingMode, TimeCharacteristic}
import org.apache.flink.api.common.restartstrategy.RestartStrategies
import org.apache.flink.streaming.api.windowing.time.Time

object FlinkStreamingApp {
  def main(args: Array[String]): Unit = {
    // Create execution environment
    val env = StreamExecutionEnvironment.getExecutionEnvironment
    
    // Configure the environment
    env.setParallelism(4)
    env.setStreamTimeCharacteristic(TimeCharacteristic.EventTime)
    env.enableCheckpointing(5000, CheckpointingMode.EXACTLY_ONCE)
    env.setRestartStrategy(RestartStrategies.fixedDelayRestart(3, 10000))
    
    // Create and process your data streams
    val stream = env.socketTextStream("localhost", 9999)
      .flatMap(_.toLowerCase.split("\\W+"))
      .filter(_.nonEmpty)
      .map((_, 1))
      .keyBy(0)
      .timeWindow(Time.minutes(1))
      .sum(1)
    
    // Add sink
    stream.print()
    
    // Execute the program
    env.execute("Word Count Streaming")
  }
}