Plugins can now only be Scala sources. BND should be usable in a plugin now.

sbt/src/main/scala/sbt/BuilderProject.scala

@@ -135,6 +135,8 @@ final class BuilderProject(val info: ProjectInfo, val pluginPath: Path, rawLogge
 	final class PluginBuilderProject(val info: ProjectInfo) extends BasicBuilderProject with ReflectiveTasks
 	{
 		override def name = "Plugin Builder"
+	// don't include Java sources because BND includes Java sources in its jar (#85)
+		def pluginSourceFilter: NameFilter = "*.scala"
 		lazy val pluginUptodate = propertyOptional[Boolean](false)
 		def tpe = "plugin definition"
 		def managedSourcePath = path(BasicDependencyPaths.DefaultManagedSourceDirectoryName)
@@ -167,7 +169,7 @@ final class BuilderProject(val info: ProjectInfo, val pluginPath: Path, rawLogge
 		{
 			FileUtilities.clean(managedSourcePath, log) orElse
 			Control.lazyFold(plugins.get.toList) { jar =>
-				Control.thread(FileUtilities.unzip(jar, extractTo(jar), sourceFilter, log)) { extracted =>
+				Control.thread(FileUtilities.unzip(jar, extractTo(jar), pluginSourceFilter, log)) { extracted =>
 					if(!extracted.isEmpty)
 						logInfo("\tExtracted source plugin " + jar + " ...")
 					None

sbt/src/sbt-test/project/src-plugins/changes/JavaTest.java

@@ -0,0 +1,4 @@
+
+// should not be interpreted as a source file
+public class JavaTest {
+}

sbt/src/sbt-test/project/src-plugins/changes/TestPlugin.scala

@@ -2,5 +2,19 @@ import sbt._
 
 trait TestPlugin extends DefaultProject
 {
-	lazy val check = task { log.info("Test action"); None }
+	lazy val check =
+		task
+		{
+			try
+			{
+				Class.forName("JavaTest")
+				Some("Java source should not be compiled as part of the plugin")
+			}
+			catch
+			{
+				case _: ClassNotFoundException =>
+					log.info("Test action")
+					None
+			}
+		}
 }

sbt/src/sbt-test/project/src-plugins/test

@@ -1,4 +1,5 @@
 $ copy-file changes/TestPlugin.scala src/main/scala/TestPlugin.scala
+$ copy-file changes/JavaTest.java src/main/java/JavaTest.java
 > publish
 
 > set project.name use-plugin-test