1.首先在 project/plugins.sbt: 下加入这段代码：
addSbtPlugin("com.eed3si9n" % "sbt-assembly" % "0.11.2")
2.先对project 执行sbt 看看能不能通过 记住要在机子上装好Git
3.在根目录创建assembly.sbt文件，内容如下：
import AssemblyKeys._ // put this at the top of the file
assemblySettings
// your assembly settings here
之后就可以sbt assembly来打包了，生成./target/scala_x.x.x/projectname-assembly-x.x.x.jar
4.如果想更详细的配置assembly，可以这样
在assembly.sbt内写入：
import AssemblyKeys._
assemblySettings
jarName in assembly := "spark_sbt.jar"
test in assembly := {}
mainClass in assembly := Some( "Spark_Test")
assemblyOption in packageDependency ~= { _.copy(appendContentHash = true) }
mergeStrategy in assembly <<= (mergeStrategy in assembly) { (old) =>
{
case PathList(ps @ _*) if ps.last endsWith "axiom.xml" => MergeStrategy.filterDistinctLines
case PathList(ps @ _*) if ps.last endsWith "Log.class" => MergeStrategy.first
case PathList(ps @ _*) if ps.last endsWith "LogConfigurationException.class" => MergeStrategy.first
case PathList(ps @ _*) if ps.last endsWith "LogFactory.class" => MergeStrategy.first
case PathList(ps @ _*) if ps.last endsWith "SimpleLog$1.class" => MergeStrategy.first
case x => old(x)
}
}