如何写一个猪UDF斯卡拉 [英] How to write a Pig UDF in Scala

问题描述

我试图写一个猪UDF在斯卡拉（使用Eclipse）。我已经加入pig.jar作为Java构建路径库，这似乎解决以下2进口：

I am trying to write a Pig UDF in Scala (using Eclipse). I have added pig.jar as a library in the java build path which seems to resolve the 2 imports below:

• 进口org.apache.pig.EvalFunc


• 进口org.apache.pig.data.Tuple

但是我得到2个错误，我不能解析：

however I get 2 errors which I cannot resolve:

1. org.apache.pig.EvalFunc [T]不具有构造


2. 的价值得到的并不是org.apache.pig.data.Tuple的成员（虽然我确信元组get方法）

下面是完整的code：

Here is the full code:

package datesUDFs
import org.apache.pig.EvalFunc
import org.apache.pig.data.Tuple
class getYear extends EvalFunc {
  val extractDate = """^(\d\d\d\d)-\d\d-\d\d \d\d:\d\d:\d\d""".r
  def isDate(dtString: String): Boolean = extractDate.findFirstIn(dtString).nonEmpty

  override def exec(input: Tuple): Int = input.get(0) match {
    case dtString: String =>
      if (!isDate(dtString)) throw new IllegalArgumentException("Invalid date string!")
      else (for (extractDate(year) <- extractDate.findFirstIn(dtString)) yield year).head.toInt
    case _ => throw new IllegalArgumentException("Invalid function call!")
  }
}

任何人可以帮助我解决这个问题？

Can anybody help me resolving this issue?

在此先感谢！

推荐答案

解决它！我加的 Hadoop的共2.2.0.jar 和的commons-logging-1.1.3.jar ，以我的Java构建路径和解决了问题。

solved it! I added hadoop-common-2.2.0.jar and commons-logging-1.1.3.jar to my java build path and the problems were resolved.

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