[英]dynamical creating a new instance of a case class in scala
Given a reference to a case class companion object t
and a sequence of parameter seq
how can I invoke a new instance of the case class? 给定对case类伴随对象
t
的引用和参数seq
的序列如何调用case类的新实例?
I can create a class when I type the number of the parameter by myself. 当我自己键入参数的数量时,我可以创建一个类。
scala> case class B(n:String,a:Int,b:Int)
defined class B
scala> val t:AnyRef = B
t: AnyRef = B
scala> val m = t.getClass.getMethods.filter{m => m.getName == "apply"}.
filterNot {_.getReturnType.getName == "java.lang.Object"}(0)
m: java.lang.reflect.Method = public B B$.apply(java.lang.String,int,int)
scala> m.invoke(t,"name",1:java.lang.Integer,2:java.lang.Integer)
res99: Object = B(name,1,2)
The problem I couldn't solve is to call invoke with a sequence of arguments like Seq("name",1:java.lang.Integer,2:java.lang.Integer)
. 我无法解决的问题是使用一系列参数调用invoke,如
Seq("name",1:java.lang.Integer,2:java.lang.Integer)
。 Any help how to do that is greatly appreciated. 任何帮助如何做到这一点非常感谢。
I use scala 2.10.0. 我使用scala 2.10.0。
Just found it out by myself (respectively have seen it over here https://stackoverflow.com/a/2060503/55070 ). 只是自己找到它(分别在这里看到它https://stackoverflow.com/a/2060503/55070 )。 It's
它的
method.invoke(t,seq: _*)
Sometimes it really helps to just write it down ;-) 有时候把它写下来确实很有帮助;-)
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