scala.util.Try does not wrap Exception when used with Future and Play WS -

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my understanding scala.util.try wraps exceptions thrown code inside try { ... } block.

here simple example wraps nullpointerexception. 

object trydemo extends app {    import scala.util.{failure, success, try}    def dosomething(i: int): string = {     if (i > 50) {       println("going throw nullpointerexception @ index " + i)       throw new nullpointerexception("- exception @ index " + i)     }     else       "some-result"   }    val t: try[string] = try {     var x = 0     while (x < 100) {       dosomething(x)       x += 1     }     "result-" + x   }    val result: option[string] = t match {     case success(s) => println("success " + s); some(s)     case failure(f) => println("failure " + f.getmessage()); none   } }

this gives following output excepted.

going throw nullpointerexception @ index 51

failure - exception @ index 51

however, when try following (with invalid url ensure fails every time) 

import play.api.libs.ws._ val wsurl = "http://invalidurl:9000/something"  val wsres: try[future[response]] = try {   ws.url(wsurl).withrequesttimeout(200).withquerystring(("param", value)).get }

exceptions thrown instead of getting error wrapped inside try. can please explain why works in first case , not in second ? 

[info]   java.net.connectexception: http://invalidurl:9000/something [info]   @ com.ning.http.client.providers.netty.nettyconnectlistener.operationcomplete(nettyconnectlistener.java:103) [info]   @ org.jboss.netty.channel.defaultchannelfuture.notifylistener(defaultchannelfuture.java:427) [info]   @ org.jboss.netty.channel.defaultchannelfuture.addlistener(defaultchannelfuture.java:145) [info]   @ com.ning.http.client.providers.netty.nettyasynchttpprovider.doconnect(nettyasynchttpprovider.java:1068) [info]   @ com.ning.http.client.providers.netty.nettyasynchttpprovider.execute(nettyasynchttpprovider.java:890) [info]   @ com.ning.http.client.asynchttpclient.executerequest(asynchttpclient.java:520) [info]   @ play.api.libs.ws.ws$wsrequest.execute(ws.scala:177) [info]   @ play.api.libs.ws.ws$wsrequestholder.get(ws.scala:386) [info]   @ controllers.geojson.geojsontransfomer$$anonfun$9.apply(geojsontransformer.scala:155) [info]   @ controllers.geojson.geojsontransfomer$$anonfun$9.apply(geojsontransformer.scala:155) [info]   ... [info]   cause: java.nio.channels.unresolvedaddressexception: [info]   @ sun.nio.ch.net.checkaddress(net.java:127) [info]   @ sun.nio.ch.socketchannelimpl.connect(socketchannelimpl.java:640) [info]   @ org.jboss.netty.channel.socket.nio.nioclientsocketpipelinesink.connect(nioclientsocketpipelinesink.java:108) [info]   @ org.jboss.netty.channel.socket.nio.nioclientsocketpipelinesink.eventsunk(nioclientsocketpipelinesink.java:70) [info]   @ org.jboss.netty.handler.codec.oneone.onetooneencoder.handledownstream(onetooneencoder.java:54) [info]   @ org.jboss.netty.handler.codec.http.httpclientcodec.handledownstream(httpclientcodec.java:97) [info]   @ org.jboss.netty.handler.stream.chunkedwritehandler.handledownstream(chunkedwritehandler.java:109) [info]   @ org.jboss.netty.channel.channels.connect(channels.java:634) [info]   @ org.jboss.netty.channel.abstractchannel.connect(abstractchannel.java:207) [info]   @ org.jboss.netty.bootstrap.clientbootstrap.connect(clientbootstrap.java:229)


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