playframework - Explain Build.scala in play framework -

can explain syntax build.scala in detail? example, have following build.scala:

import sbt._ import keys._ import play.project._  object build extends sbt.build {     val appname         = "myapp"    val appversion      = "1.0"     val appdependencies = seq(       "postgresql"    %   "postgresql"        % "9.1-901-1.jdbc4",       javacore,       javajdbc,       javaebean,       "org.json"      %"org.json"             % "chargebee-1.0",       "org.reflections" % "reflections" % "0.9.8",       "org.mockito"   %   "mockito-all"       % "1.9.5" % "test"     )      val main = play.project(appname, appversion, appdependencies).settings(       librarydependencies += "com.jolbox" % "bonecp" % "0.8.0-rc2-snapshot",       resolvers += resolver.url("sbt-plugin-snapshots", new url("http://repo.scala-sbt.org/scalasbt/sbt-plugin-snapshots/"))(resolver.ivystylepatterns),       resolvers += "sonatype oss snapshots" @ "https://oss.sonatype.org/content/repositories/snapshots/"     )  } 

how match appdependencies resolvers? or how know resolvers need add appdependencies? in resolver's repo? librarydependencies? how different appdependencies?

thanks.

there few things need disentangle here.

let's first distinguish between sbt build file , build.scala. while build file maven pom or gradle build file, think of build.scala build capability full power , expressiveness of scala because scala class other. believe gap between 2 has narrowed though latest version of sbt.

now in both sbt , build.scala, have notion of library dependencies, jar libraries containing code can use projects. these libraries can found in lots of places--maven repositories, local file system, etc. use resolvers specify locations.

so tell both jars need , find them.

as appdependencies, that's not thing. said, build.scala class other, , appdependencies variable name. makes sense use name because seq pass project constructor.