ujson.JsVisitor.scala Maven / Gradle / Ivy

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package ujson

import upickle.core.{ArrVisitor, ObjVisitor, Visitor}

/**
  * A [[Visitor]] specialized to work with JSON types. Forwards the
  * not-JSON-related methods to their JSON equivalents.
  */
trait JsVisitor[-T, +J] extends Visitor[T, J]{
  def visitFloat64(d: Double, index: Int): J = {
    if (d == Double.PositiveInfinity) visitString("Infinity", index)
    else if (d == Double.NegativeInfinity) visitString("-Infinity", index)
    else {
      val i = d.toLong
      if(i == d) visitFloat64StringParts(i.toString, -1, -1, index)
      else visitFloat64String(d.toString, index)
    }
  }

  def visitFloat32(d: Float, index: Int): J = {
    if (d == Float.PositiveInfinity) visitString("Infinity", index)
    else if (d == Float.NegativeInfinity) visitString("-Infinity", index)
    else {
      val i = d.toLong
      if (i == d) visitFloat64StringParts(i.toString, -1, -1, index)
      else visitFloat64String(d.toString, index)
    }
  }

  def visitInt32(i: Int, index: Int): J = visitFloat64(i, index)
  def visitInt64(i: Long, index: Int): J = {
    if (math.abs(i) > 9007199254740992L /*math.pow(2, 53)*/ ||
        i == -9223372036854775808L /*Long.MinValue*/) visitString(i.toString, index)
    else visitFloat64(i.toDouble, index)
  }
  def visitUInt64(i: Long, index: Int): J = {
    if (i > 9007199254740992L /*math.pow(2, 53)*/ ||
        i < 0) visitString(java.lang.Long.toUnsignedString(i), index)
    else visitFloat64(i.toDouble, index)
  }
  def visitFloat64String(s: String, index: Int): J = {
    visitFloat64StringParts(
      s,
      s.indexOf('.'),
      s.indexOf('E') match{
        case -1 => s.indexOf('e')
        case n => n
      },
      -1
    )
  }

  def visitBinary(bytes: Array[Byte], offset: Int, len: Int, index: Int): J = {
    val arr = visitArray(len, index)
    var i = 0
    while (i < len){
      arr.visitValue(arr.subVisitor.visitInt32(bytes(offset + i), index).asInstanceOf[T], index)
      i += 1
    }
    arr.visitEnd(index)
  }

  def visitFloat64StringParts(s: CharSequence, decIndex: Int, expIndex: Int): J = visitFloat64StringParts(s, decIndex, expIndex, -1)

  def visitExt(tag: Byte, bytes: Array[Byte], offset: Int, len: Int, index: Int): J = {
    val arr = visitArray(-1, index)
    arr.visitValue(visitFloat64(tag, index).asInstanceOf[T], -1)
    arr.visitValue(visitBinary(bytes, offset, len, index).asInstanceOf[T], -1)
    arr.visitEnd(-1)
  }

  def visitChar(s: Char, index: Int) = visitString(s.toString, index)

  def visitJsonableObject(length: Int, index: Int): ObjVisitor[T, J]

  override def visitObject(length: Int, jsonableKeys: Boolean, index: Int) = {
    if (jsonableKeys) visitJsonableObject(length, index)
    else new ObjVisitor[T, J] {
      val wrapped = visitArray(length, index)
      var lastKeyIndex = -1
      var lastNested: ArrVisitor[T, T] = null
      def subVisitor = JsVisitor.this
      def visitKey(index: Int) = {
        lastNested = wrapped.subVisitor.visitArray(2, index).asInstanceOf[ArrVisitor[T, T]]
        lastKeyIndex = index
        JsVisitor.this
      }

      def visitKeyValue(s: Any): Unit = {
        lastNested.visitValue(s.asInstanceOf[T], lastKeyIndex)
      }

      def visitValue(v: T, index: Int): Unit = {
        lastNested.visitValue(v, index)
        wrapped.visitValue(lastNested.visitEnd(index), index)
      }

      def visitEnd(index: Int) = wrapped.visitEnd(index)
    }

  }
}