scala for each loop got error when convert java to scala

Question

i am working with scala in few days. and i am really confused with this problem .

i really tried to solve the peoblem but i can't..

My java code

@Override
    public void saveOrUpdateAll(Collection<T> entities) {
        Session session = getSession();
        for (T entity : entities) {
            session.saveOrUpdate(entity);
        }
    }

Scala Code

@Override
    def  saveOrUpdateAll( entities:Collection[T]){
        var session:Session = getSession()
        var entity:T=null
        for (entity :entities) {
            session.saveOrUpdate(entity);
        }
    }

search for scala for each. and am really confused about that .. if you know how to solve this problem please share your answer here.. and Thanx..

with regards Milano.. :)

You want <- instead of : in the for in Scala, and you don't need the var entity line at all. — Rex Kerr
– Rex Kerr, Commented Jul 8, 2013 at 5:31
@RexKerr u r r8.. pls answer it and i will mark as correct answer and this is really help full ans thankx... — Prasanth A R
– Prasanth A R, Commented Jul 8, 2013 at 5:35
@RexKerr mm.. okay.. your r r8.. and really thanks for your comments.. it's really helpful — Prasanth A R
– Prasanth A R, Commented Jul 8, 2013 at 5:43

Community · Accepted Answer · 2017-05-23 12:29:00Z

3

override def saveOrUpdateAll(entities: Collection[T]){
  import scala.collection.JavaConverters._

  val session: Session = getSession()

  for (entity <- entities.asScala) {
      session.saveOrUpdate(entity)
  }
}

There is no for each loop in scala. You should wrap your collection using JavaConverters and use for-comprehension here.

JavaConverters wraps Collection using Wrappers.JCollectionWrapper without memory overhead.

edited May 23, 2017 at 12:29

CommunityBot

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answered Jul 8, 2013 at 5:35

senia

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1 Comment

senia Over a year ago

@milano: if you want to override a method of parent class you should use override modifier.

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