是否可以在Scala中实现类构造函数类型转换器

Question

例如我有这个课程

 import java.sql.Timestamp

 class Service(name: String, stime: Timestamp,
          etime:Timestamp)

如何让它以隐式方式接受以下内容，让我们调用stringToTimestampConverter

    val s = new AService("service1", "2015-2-15 07:15:43", "2015-2-15 10:15:43")

时间已经作为字符串传递。

如何实现这样的转换器？

Answer 1

你有两种方式，第一种是在范围内有一个String =＆gt;时间戳隐式转换

// Just have this in scope before you instantiate the object
implicit def toTimestamp(s: String): Timestamp = Timestamp.valueOf(s) // convert to timestamp

另一个是在类中添加另一个构造函数：

class Service(name: String, stime: Timestamp, etime:Timestamp) {
  def this(name: String, stime: String, etime: String) = {
    this(name, Service.toTimestamp(stime), Service.toTimestamp(etime))
  }
}

object Service {
  def toTimestamp(s: String): Timestamp = Timestamp.valueOf(s) // convert to timestamp
}