scala

GCAdaptive.scala

package gclogreader

import scala.io.Source
import scala.util.matching.Regex

object GCAdaptive extends App {



  val filename = raw"C:\Users\Dixson\gc_pid16200.log"

  def process_young(s: String): Unit = {

    // (?s) - DOTALL, (?m) - MULTILINE
    val youngR = raw"(?s)(?m)^(\d*\.\d*): \[GC pause [ \w\(\)]* \(young\).+?, (\d*\.\d*) secs\]$$".r

    val m = youngR.findAllIn(s)
    while (m.hasNext) {
      val young = m.next
      val process_time = m.group(1)
      val gc_time = m.group(2)
      println(s"GC pause (young), $process_time, $gc_time")
    }
  }

  def process_mixed(s: String): Unit = {

    // (?s) - DOTALL, (?m) - MULTILINE
    val mixedR: Regex = raw"(?s)(?m)^(\d*\.\d*): \[GC pause \(mixed\).+?, (\d*\.\d*) secs\]$$".r

    val m = mixedR.findAllIn(s)
    while (m.hasNext) {
      val young = m.next
      val process_time = m.group(1)
      val gc_time = m.group(2)
      println(s"GC pause (mixed), $process_time, $gc_time")
    }
  }

  def process_remark_cleanup_fullgc(s: String): Unit = {

    var (gc_type, process_time, gc_time, gc_size_before, gc_size_after, total_size) = ("", "", "", "", "", "")

    // not quite raw - need $$ to escape String interpolation
    val remarkR  = raw"^(\d*\.\d*): \[GC remark \d*\.\d*: .+, (\d*\.\d*) secs\]$$".r()
    val cleanupR = raw"^(\d*\.\d*): \[GC cleanup .+, (\d*\.\d*) secs\]$$".r()
    val fullgcR  = raw"^(\d*\.\d*): \[Full GC.+ (\d+[MG])->(\d*[MG])\((\d*[MG])\), (\d*\.\d*) secs\]$$".r()

    // match regex
    val m: Option[String] = s match {
      case remarkR(a, b) => gc_type = "GC remark"
        process_time = a
        gc_time = b
        Some(s)
      case cleanupR(a, b) => gc_type = "GC cleanup"
        process_time = a
        gc_time = b
        Some(s)
      case fullgcR(proc_t, before, after, size, gc_t) =>
        gc_type = "Full GC"
        process_time = proc_t
        gc_size_before = before
        gc_size_after = after
        total_size = size
        gc_time = gc_t
        Some(s)
      case _ => None
    }

    if( m.isDefined ) {
      if( gc_size_after != "")
        println(s"$gc_type, $process_time, $gc_time, $gc_size_before, $gc_size_after, $total_size")
      else
        println(s"$gc_type, $process_time, $gc_time")
      println(m.get)
    }
  }



  for (line <- Source.fromFile(filename).getLines) {
    //println(line)

    line match {
      case l if l.startsWith(" ") == false => process_remark_cleanup_fullgc(line)
      case _ =>
    }
  }

  // requires multi-line processing
  val text : String =  Source.fromFile(filename).getLines.toList.mkString(scala.util.Properties.lineSeparator)

  process_young(text)
  process_mixed(text)
}