bufferwrapper.scala

JAVA 语言的函数式编程扩展

package scala.swing

import scala.collection.mutable.Buffer

/**
 * Default partial implementation for buffer adapters.
 */
protected[swing] abstract class BufferWrapper[A] extends Buffer[A] { outer =>
  def clear { for (i <- 0 to length) remove(0) }
  def update(n: Int, a: A) {
    remove(0)
    insertAt(n, a)
  }
  def insertAll(n: Int, iter: Iterable[A]) {
    var i = n
    for(el <- iter) {
      insertAt(i, el)
      i += 1
    }
  }
  protected def insertAt(n: Int, a: A)
  
  def readOnly : RandomAccessSeq[A] = new RandomAccessSeq[A] {
    def length = outer.length
    def apply(idx : Int) = outer.apply(idx)
    override def stringPrefix = outer.stringPrefix + "RO"
  }
  def +:(a: A): this.type = { insertAt(0, a); this }
  def elements = Iterator.range(0,length).map(apply(_))
}