pos打印小票如何设置行间距

export class PosMachine {
constructor (ipAddr, port) {
if (plus.os.name == 'Android') {
var Socket = plus.android.importClass('java.net.Socket')
var PrintWriter = plus.android.importClass('java.io.PrintWriter')
var BufferedWriter = plus.android.importClass('java.io.BufferedWriter')
var OutputStreamWriter = plus.android.importClass('java.io.OutputStreamWriter')
var BufferedReader = plus.android.importClass('java.io.BufferedReader')
var InputStreamReader = plus.android.importClass('java.io.InputStreamReader')
var StrictMode = plus.android.importClass('android.os.StrictMode')
var Build = plus.android.importClass('android.os.Build')
if (Build.VERSION.SDK_INT > 9) {
var policy = new StrictMode.ThreadPolicy.Builder().permitAll().build()
StrictMode.setThreadPolicy(policy)
}
var socket = new Socket(ipAddr, port)

  var outputStreamWriter = new OutputStreamWriter(socket.getOutputStream(), 'gbk')  
  var bufferWriter = new BufferedWriter(outputStreamWriter)  
  this.posMaWriter = new PrintWriter(bufferWriter, true)  
}  

}
setBold (flag) {
if (flag) {
this.posMaWriter.write(0x1B)
this.posMaWriter.write(69)
this.posMaWriter.write(0xF)
} else {
this.posMaWriter.write(0x1B)
this.posMaWriter.write(69)
this.posMaWriter.write(0)
}
}

/**

• 排版
• @param position 0：居左(默认) 1：居中 2：居右
• @return
• @throws IOException
  */
  setAlign (position) {
  this.posMaWriter.write(0x1B)
  this.posMaWriter.write(97)
  this.posMaWriter.write(position)
  }
  /**
• 字体大小
• @param size 1-8 选择字号
• @return
• @throws IOException
  */
  setSize (size) {
  this.posMaWriter.write(0x1D)
  this.posMaWriter.write(33)
  this.posMaWriter.write(size)
  }
  /**
• 进纸并全部切割
• @return
• @throws IOException
  */
  feedAndCut () {
  this.posMaWriter.write(0x1D)
  this.posMaWriter.write(86)
  this.posMaWriter.write(65)
  this.posMaWriter.write(0)
  this.posMaWriter.flush()
  }
  getPosHandle () {
  return this.posMaWriter
  }
  }

谢谢