stream學習二

var stream = require('stream')
var util = require('util')
function ReadStream() {
    stream.Readable.call(this)
}

util.inherits(ReadStream,stream.Readable)

ReadStream.prototype._read = function () {
    this.push('I')
    this.push('Love')
    this.push('Imooc\n')
    this.push(null)
}

function WritStream() {
    stream.Writable.call(this)
    this._cached = new Buffer('')
}
util.inherits(WritStream,stream.Writable)

WritStream.prototype._write = function (chunk,encode,cb) {
    console.log(chunk.toString())
    cb()
}

function TransformStream() {
    stream.Transform.call(this)
}
util.inherits(TransformStream,stream.Transform)
TransformStream.prototype._transform = function (chunk,encode,cb) {
    this.push(chunk)
    cb()
}
TransformStream.prototype._flush = function (cb) {
    this.push('On Yeah!')
    cb()
}
var rs = new ReadStream()
var ws = new WritStream()
var ts = new TransformStream()
rs.pipe(ts).pipe(ws)