in extractor-legacy-0.13/src/main/scala/org/jetbrains/sbt/extractors/UtilityTasks.scala [186:196]
def writeToFile(file: File, xml: String): Unit = {
val writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), "UTF-8"))
try {
writer.write("""<?xml version="1.0" encoding="UTF-8"?>""")
writer.newLine()
writer.write(xml)
writer.flush()
} finally {
writer.close()
}
}