Now can download .pack.xz file for Forge library.

HMCLAPI/src/main/java/org/tukaani/xz/DeltaEncoder.java

@@ -0,0 +1,36 @@
+/*
+ * DeltaEncoder
+ *
+ * Author: Lasse Collin <lasse.collin@tukaani.org>
+ *
+ * This file has been put into the public domain.
+ * You can do whatever you want with this file.
+ */
+
+package org.tukaani.xz;
+
+class DeltaEncoder extends DeltaCoder implements FilterEncoder {
+    private final DeltaOptions options;
+    private final byte[] props = new byte[1];
+
+    DeltaEncoder(DeltaOptions options) {
+        props[0] = (byte)(options.getDistance() - 1);
+        this.options = (DeltaOptions)options.clone();
+    }
+
+    public long getFilterID() {
+        return FILTER_ID;
+    }
+
+    public byte[] getFilterProps() {
+        return props;
+    }
+
+    public boolean supportsFlushing() {
+        return true;
+    }
+
+    public FinishableOutputStream getOutputStream(FinishableOutputStream out) {
+        return options.getOutputStream(out);
+    }
+}