diff -r 158c513a39f5 -r 9098c36abd1a src/Tools/jEdit/src-base/isabelle_encoding.scala
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Tools/jEdit/src-base/isabelle_encoding.scala	Sun Aug 20 14:03:23 2017 +0200
@@ -0,0 +1,54 @@
+/*  Title:      Tools/jEdit/src-base/isabelle_encoding.scala
+    Author:     Makarius
+
+Isabelle encoding -- based on UTF-8.
+*/
+
+package isabelle.jedit_base
+
+
+import isabelle._
+
+import org.gjt.sp.jedit.io.Encoding
+
+import java.nio.charset.{Charset, CodingErrorAction}
+import java.io.{InputStream, OutputStream, Reader, Writer, InputStreamReader, OutputStreamWriter,
+  CharArrayReader, ByteArrayOutputStream}
+
+import scala.io.{Codec, BufferedSource}
+
+
+class Isabelle_Encoding extends Encoding
+{
+  private val BUFSIZE = 32768
+
+  private def text_reader(in: InputStream, codec: Codec): Reader =
+  {
+    val source = new BufferedSource(in)(codec)
+    new CharArrayReader(Symbol.decode(source.mkString).toArray)
+  }
+
+  override def getTextReader(in: InputStream): Reader = text_reader(in, UTF8.codec())
+
+  override def getPermissiveTextReader(in: InputStream): Reader =
+  {
+    val codec = UTF8.codec()
+    codec.onMalformedInput(CodingErrorAction.REPLACE)
+    codec.onUnmappableCharacter(CodingErrorAction.REPLACE)
+    text_reader(in, codec)
+  }
+
+  override def getTextWriter(out: OutputStream): Writer =
+  {
+    val buffer = new ByteArrayOutputStream(BUFSIZE) {
+      override def flush()
+      {
+        val text = Symbol.encode(toString(UTF8.charset_name))
+        out.write(UTF8.bytes(text))
+        out.flush()
+      }
+      override def close() { out.close() }
+    }
+    new OutputStreamWriter(buffer, UTF8.charset.newEncoder())
+  }
+}