hibernate - 如何在 Scala 中实现 org.hibernate.Session

Question

“Session”接口(interface)有两个方法，在 Scala 中，由于类型删除，它们被简化为具有相同的签名:

public ProcedureCall createStoredProcedureCall(String procedureName, Class... resultClasses)

public ProcedureCall createStoredProcedureCall(String procedureName, String... resultSetMappings)

尝试实现它们会出现错误:

错误:双重定义:方法 createStoredProcedureCall:(procedureName: String, resultSetMappings: String*)org.hibernate.procedure.ProcedureCall 和第 199 行的方法 createStoredProcedureCall:(procedureName: String, resultClasses: Class[_])org.hibernate.procedure.ProcedureCall删除后具有相同的类型: (procedureName: String, resultSetMappings: Seq)org.hibernate.procedure.ProcedureCall override def createStoredProcedureCall(procedureName: String, resultSetMappings: String): procedureCall = null ^

那么我该如何以既能编译又能工作的方式实现这个接口(interface)呢？

Answer 1

如serejja指出，您可以用 Java 编写一个 shim 来为您进行翻译:

Java:

package jibernate;

import org.hibernate.procedure.ProcedureCall;
import org.hibernate.SharedSessionContract;

public abstract class Yava implements SharedSessionContract {

  public ProcedureCall createStoredProcedureCallC(String n, Class... xs) {
    return createStoredProcedureCall(n, xs);
  }

  public ProcedureCall createStoredProcedureCallS(String n, String... xs) {
    return createStoredProcedureCall(n, xs);
  }

}

如果您使用 sbt，它可以位于 src/main/java/jibernate/Yava.java

Scala:

package whybernate

trait Mehssion extends jibernate.Yava {

  import org.hibernate.procedure.ProcedureCall

  def createStoredProcedureCall(n: String, h: Class[_], t: Class[_]*) =
    createStoredProcedureCallC(n, (h +: t):_*)

  def createStoredProcedureCall(n: String, h: String, t: String*) =
    createStoredProcedureCallS(n, (h +: t):_*)

}

您可以以相同的方式调用这些函数，利用这样一个事实，即您保证至少拥有一个所需的可变参数。