32_io_四个缓冲流_02

import java.io._

/*
*
*
*
* */

// 4. BufferedReader & BufferedWriter
object BufferCharStreamTest extends App {
  // 读取数据
  // 1. 创建File + FileReader + BufferedReader
  val inPath = "sparkcore/src/main/data/word.txt"
  private val bufferedReader = new BufferedReader(new FileReader(new File(inPath)))

  // 2. 创建File + FileWriter + BufferedWriter
  val outPath = "sparkcore/src/main/data/bufferedOut.txt"
  private val bufferedWriter = new BufferedWriter(new FileWriter(new File(outPath)))

  // 3. 读取数据
  private var str: String = bufferedReader.readLine
  while (str != null) {
    println(str)
    str = bufferedReader.readLine
  }

  // 4. 关闭流
  bufferedReader.close
  println("读取完毕")

  //写入数据
  private val strings: Array[String] = Array[String]("悟空\n", "八戒\n", "沙僧\n", "三藏\n")
  strings.foreach(bufferedWriter.write)

  //关闭流
  bufferedWriter.close
  println("写入完毕")


}

// 5. BufferedInputStream & BufferOutputStream
object BufferByteStreamTest extends App {
  //1. 创建File + FileInputStream + BufferedInputStream 对象
  val inPath = "sparkcore/src/main/data/yarn架构图.png"
  private val bufferedInputStream = new BufferedInputStream(new FileInputStream(inPath))

  //2. 创建File + FileOutputStream + BufferedOutputStream 对象
  val outPath = "sparkcore/src/main/data/yarn架构图2.png"
  private val bufferedOutputStream = new BufferedOutputStream(new FileOutputStream(outPath))

  //读取数据
  private var bytes: Array[Byte] = new Array[Byte](10)
  private var i: Int = bufferedInputStream.read(bytes)
  while (i != -1) {
    println(bytes.mkString("   "))
    i = bufferedInputStream.read(bytes, 0, i)
  }
  //  0     0  0  73  69  78  68  -82  66  96  倒数第二行
  //  -126  0  0  73  69  78  68  -82  66  96  倒数第一行

  // 关闭流
  bufferedInputStream.close
  println("读取完成")

  // 写入数据
  bufferedOutputStream.write(100)

  // 关闭流
  bufferedOutputStream.close


}

// 6. BufferedInputStream & BufferOutputStream - 复制非文本文件 及测速 10毫秒
object CopyFileByBufferTest extends App {
  // 定义方法
  // 复制inPath指定的文件 到outPath指定的文件
  def copyFile(inPath: String, outPath: String) = {
    //1. 创建File对象 + FileInputSteam对象
    val inStream = new BufferedInputStream(new FileInputStream(inPath)) //new FileInputStream(new File(inPath))

    //2. 创建File对象 + FileOutputSteam对象
    val outStream = new BufferedOutputStream(new FileOutputStream(outPath)) //new FileOutputStream(new File(outPath))

    //3. 读取
    var bytes = new Array[Byte](10)
    var i: Int = inStream.read(bytes)
    while (i != -1) {
      outStream.write(bytes, 0, i)
      i = inStream.read(bytes)
    }

    //4. 关闭流
    inStream.close
    outStream.close
  }

  //调用方法
  val inPath = "sparkcore/src/main/data/yarn架构图.png"
  val outPath = "sparkcore/src/main/data/yarn架构图1.png"

  //计时
  val start: Long = System.currentTimeMillis
  copyFile(inPath, outPath)
  val end: Long = System.currentTimeMillis
  println(s"耗时 : ${end - start}毫秒")


}