不是特别懂，但感觉和RUBY当中的MIX-IN功能有几分相似，这又扯到了多重继承及JAVA当中的接口虚拟类了。。
package com.hengheng.scala
class UseTrait {
}
trait Logger {
def log(msg : String) {
println("log : " + msg)
}
}
trait ConsoleLogger extends Logger {
override def log(msg : String) {
println(msg)
}
}
class Test extends ConsoleLogger {
def test() {
log("Here is Spark!")
}
}
class ConcreteLogger extends Logger {
def concreteLog {
log("It's me!")
}
}
object UseTrait extends App {
var logger = new ConcreteLogger
logger.concreteLog
var test = new Test
test.test
}
输出：
log : It's me!
Here is Spark!