added -jar option to scala interpreter

3 files changed, 64 insertions, 15 deletions

diff --git a/src/compiler/scala/tools/nsc/GenericRunnerCommand.scala b/src/compiler/scala/tools/nsc/GenericRunnerCommand.scala
index c088bb9303..7f32fb3653 100644
--- a/src/compiler/scala/tools/nsc/GenericRunnerCommand.scala
+++ b/src/compiler/scala/tools/nsc/GenericRunnerCommand.scala
@@ -33,13 +33,19 @@ extends CompilerCommand(args, settings) {
     case hd :: tl => (Some(hd), tl)
   }
 
-  override def usageMsg = """
-%s [ <option> ]... [<torun> <arguments>]
+  override def usageMsg ="""
+Usage: %s <options> [<torun> <arguments>]
+   or  %s <options> [-jar <jarfile> <arguments>]
 
 All options to %s are allowed.  See %s -help.
 
 <torun>, if present, is an object or script file to run.
-If no <torun> is present, run an interactive shell.
+
+-jar <jarfile>, if present, uses the 'Main-Class' attribute
+in the manifest file to determine the object to run.
+
+If neither <torun> nor -jar <jarfile> are present, run an
+interactive shell.
 
 Option -howtorun allows explicitly specifying how to run <torun>:
     script: it is a script file
@@ -57,5 +63,5 @@ for future use.
 Option -nocompdaemon requests that the fsc offline compiler not be used.
 
 Option -Dproperty=value sets a Java system property.
-""".format(cmdName, compCmdName, compCmdName)
+""".format(cmdName, cmdName, compCmdName, compCmdName)
 }
diff --git a/src/compiler/scala/tools/nsc/GenericRunnerSettings.scala b/src/compiler/scala/tools/nsc/GenericRunnerSettings.scala
index 5d272b06ae..65fdb82bd2 100644
--- a/src/compiler/scala/tools/nsc/GenericRunnerSettings.scala
+++ b/src/compiler/scala/tools/nsc/GenericRunnerSettings.scala
@@ -8,6 +8,13 @@ package scala.tools.nsc
 
 class GenericRunnerSettings(error: String => Unit)
 extends Settings(error) {
+  val jarfile =
+    StringSetting(
+      "-jar",
+      "jar",
+      "Specify the jarfile in which to look for the main class",
+      "")
+
   val howtorun =
     ChoiceSetting(
       "-howtorun",
@@ -17,24 +24,24 @@ extends Settings(error) {
 
   val loadfiles =
     MultiStringSetting(
-        "-i",
-        "file",
-        "load a file (assumes the code is given interactively)")
+      "-i",
+      "file",
+      "load a file (assumes the code is given interactively)")
 
   val execute =
     StringSetting(
-        "-e",
-        "string",
-        "execute a single command",
-        "")
+      "-e",
+      "string",
+      "execute a single command",
+      "")
 
   val savecompiled =
     BooleanSetting(
-        "-savecompiled",
-        "save the compiled script (assumes the code is a script)")
+      "-savecompiled",
+      "save the compiled script (assumes the code is a script)")
 
   val nocompdaemon =
     BooleanSetting(
-        "-nocompdaemon",
-        "do not use the fsc compilation daemon")
+      "-nocompdaemon",
+      "do not use the fsc compilation daemon")
 }
diff --git a/src/compiler/scala/tools/nsc/settings/MutableSettings.scala b/src/compiler/scala/tools/nsc/settings/MutableSettings.scala
index 9b7b838da4..04af436ea3 100644
--- a/src/compiler/scala/tools/nsc/settings/MutableSettings.scala
+++ b/src/compiler/scala/tools/nsc/settings/MutableSettings.scala
@@ -122,6 +122,32 @@ class MutableSettings(val errorFn: String => Unit) extends AbsSettings with Scal
     def parseNormalArg(p: String, args: List[String]): Option[List[String]] =
       tryToSetIfExists(p, args, (s: Setting) => s.tryToSet _)
 
+    def getMainClass(jarName: String): Option[String] = {
+      import java.io._, java.util.jar._
+      try {
+        val in = new JarInputStream(new FileInputStream(jarName))
+        val mf = in.getManifest
+        val res = if (mf != null) {
+          val name = mf.getMainAttributes getValue Attributes.Name.MAIN_CLASS
+          if (name != null) Some(name)
+          else {
+            errorFn("Unable to get attribute 'Main-Class' from jarfile "+jarName)
+            None
+          }
+        } else {
+          errorFn("Unable to find manifest in jarfile "+jarName)
+          None
+        }
+        in.close()
+        res
+      } catch {
+        case e: FileNotFoundException =>
+          errorFn("Unable to access jarfile "+jarName); None
+        case e: IOException =>
+          errorFn(e.getMessage); None
+      }
+    }
+
     def doArgs(args: List[String]): List[String] = {
       if (args.isEmpty) return Nil
       val arg :: rest = args
@@ -137,6 +163,16 @@ class MutableSettings(val errorFn: String => Unit) extends AbsSettings with Scal
         errorFn("'-' is not a valid argument.")
         args
       }
+      else if (arg == "-jar") {
+        parseNormalArg("-cp", rest) match {
+          case Some(xs) =>
+            getMainClass(rest.head) match {
+              case Some(mainClass) => mainClass :: xs
+              case None => args
+            }
+          case None     => args
+        }
+      }
       else
         // we dispatch differently based on the appearance of p:
         // 1) If it has a : it is presumed to be -Xfoo:bar,baz