Initial verison of reading config from files

rocket/src/main/scala/config.scala

@@ -0,0 +1,56 @@
+package rocket
+package config
+
+import java.io.File
+import java.io.FileInputStream
+import java.util.Properties
+import scala.util.{Properties => SProperties}
+
+class Config(props: Properties) {
+  private val msg = "Configuration is missing requested parameter "
+  def getInt(name: String): Int = Option(props.getProperty(name).toInt).getOrElse(sys.error(msg+name))
+  def getString(name: String): String = Option(props.getProperty(name)).getOrElse(sys.error(msg+name))
+  def getBoolean(name: String): Boolean = Option(props.getProperty(name).toBoolean).getOrElse(sys.error(msg+name))
+  def apply(name: String): Int = getInt(name)
+}
+
+object Config {
+
+  lazy val internal_config = getConfig()
+
+  def apply(name: String) = internal_config(name)
+
+  private def getConfig(): Config = {
+
+    val filePath0 = 
+      SProperties
+        .envOrNone("ROCKET_CONFIG")
+        .orElse(SProperties.propOrNone("rocket.config"))  
+    if (filePath0.isEmpty)
+      Console.err.println("""
+      | WARNING: Could not find configuration file to load. 
+      | Options are:
+      |   (1) Set environmental variable ROCKET_CONFIG to the config file path
+      |   (2) Set system property rocket.config to the config file path
+      | Using default values for config.
+      """.stripMargin)
+
+    val filePath =
+      filePath0.flatMap(fp => {
+        val f = new File(fp)
+        if (!f.isFile) {
+          Console.err.println("""
+          | WARNING: File '%s' is not a valid file path
+          | Using default values for config
+          """.format(fp).stripMargin)
+          None
+        } else Some(fp)
+      })
+
+    val props = new Properties()
+    filePath.map(fp => props.load(new FileInputStream(fp)))
+    new Config(props)
+  }
+
+}
+

rocket/src/main/scala/rocket.config

@@ -0,0 +1 @@
+NWAYS 4