Scala example source code file (JavaCharArrayReader.scala)

This example Scala source code file (JavaCharArrayReader.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Scala source code examples by using tags.

All credit for the original source code belongs to scala-lang.org; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Scala tags/keywords

boolean, char, indexedseq, int, javachararrayreader, lf, string, su, su's, unit

The JavaCharArrayReader.scala Scala example source code

/* NSC -- new Scala compiler
 * Copyright 2005-2013 LAMP/EPFL
 * @author  Martin Odersky
 */

package scala
package tools.nsc
package util

import scala.reflect.internal.Chars._

class JavaCharArrayReader(buf: IndexedSeq[Char], start: Int, /* startline: int, startcol: int, */
                      decodeUni: Boolean, error: String => Unit) extends Iterator[Char] with Cloneable {

  def this(buf: IndexedSeq[Char], decodeUni: Boolean, error: String => Unit) =
    this(buf, 0, /* 1, 1, */ decodeUni, error)

  /** the line and column position of the current character
  */
  var ch: Char = _
  var bp = start
  def cpos = bp
  var isUnicode: Boolean = _

  def hasNext = bp < buf.length

  def next(): Char = {
    val buf = this.buf.asInstanceOf[collection.mutable.WrappedArray[Char]].array
    if(!hasNext) {
      ch = SU
      return SU  // there is an endless stream of SU's at the end
    }
    ch = buf(bp)
    isUnicode = false
    bp = bp + 1
    ch match {
      case '\t' =>
      case CR =>
        if (bp < buf.length && buf(bp) == LF) {
          ch = LF
          bp += 1
        }
      case LF | FF =>
      case '\\' =>
        def evenSlashPrefix: Boolean = {
          var p = bp - 2
          while (p >= 0 && buf(p) == '\\') p -= 1
          (bp - p) % 2 == 0
        }
        def udigit: Int = {
          val d = digit2int(buf(bp), 16)
          if (d >= 0) bp += 1
          else error("error in unicode escape")
          d
        }
        if (buf(bp) == 'u' && decodeUni && evenSlashPrefix) {
          do {
            bp += 1 //; nextcol += 1
          } while (buf(bp) == 'u')
          val code = udigit << 12 | udigit << 8 | udigit << 4 | udigit
          ch = code.asInstanceOf[Char]
          isUnicode = true
        }
      case _ =>
    }
    ch
  }

  def copy: JavaCharArrayReader =
    new JavaCharArrayReader(buf, bp, /* nextcol, nextline, */ decodeUni, error)
}