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diff --git a/libjava/classpath/gnu/javax/crypto/assembly/DeflateTransformer.java b/libjava/classpath/gnu/javax/crypto/assembly/DeflateTransformer.java
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+++ b/libjava/classpath/gnu/javax/crypto/assembly/DeflateTransformer.java
@@ -0,0 +1,177 @@
+/* DeflateTransformer.java --
+   Copyright (C) 2003, 2006 Free Software Foundation, Inc.
+
+This file is a part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or (at
+your option) any later version.
+
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; if not, write to the Free Software
+Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
+USA
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version.  */
+
+
+package gnu.javax.crypto.assembly;
+
+import java.util.Map;
+import java.util.zip.DataFormatException;
+import java.util.zip.Deflater;
+import java.util.zip.Inflater;
+
+/**
+ * A {@link Transformer} Adapter allowing inclusion of a DEFLATE compression
+ * algorithm in an {@link Assembly} chain. The {@link Direction#FORWARD}
+ * transformation is a compression (deflate) of input data, while the
+ * {@link Direction#REVERSED} one is a decompression (inflate) that restores the
+ * original data.
+ * <p>
+ * This {@link Transformer} uses a {@link Deflater} instance to carry on the
+ * compression, and an {@link Inflater} to do the decompression.
+ * <p>
+ * When using such a {@link Transformer}, in an {@link Assembly}, there must
+ * be at least one element behind this instance in the constructed chain;
+ * otherwise, a {@link TransformerException} is thrown at initialisation time.
+ */
+class DeflateTransformer
+    extends Transformer
+{
+  private Deflater compressor;
+
+  private Inflater decompressor;
+
+  private int outputBlockSize = 512; // default zlib buffer size
+
+  private byte[] zlibBuffer;
+
+  DeflateTransformer()
+  {
+    super();
+
+  }
+
+  void initDelegate(Map attributes) throws TransformerException
+  {
+    if (tail == null)
+      {
+        IllegalStateException cause = new IllegalStateException(
+            "Compression transformer missing its tail!");
+        throw new TransformerException("initDelegate()", cause);
+      }
+    outputBlockSize = tail.currentBlockSize();
+    zlibBuffer = new byte[outputBlockSize];
+    Direction flow = (Direction) attributes.get(DIRECTION);
+    if (flow == Direction.FORWARD)
+      compressor = new Deflater();
+    else
+      decompressor = new Inflater();
+  }
+
+  int delegateBlockSize()
+  {
+    return 1;
+  }
+
+  void resetDelegate()
+  {
+    compressor = null;
+    decompressor = null;
+    outputBlockSize = 1;
+    zlibBuffer = null;
+  }
+
+  byte[] updateDelegate(byte[] in, int offset, int length)
+      throws TransformerException
+  {
+    byte[] result;
+    if (wired == Direction.FORWARD)
+      {
+        compressor.setInput(in, offset, length);
+        while (! compressor.needsInput())
+          compress();
+      }
+    else // decompression: inflate first and then update tail
+      decompress(in, offset, length);
+    result = inBuffer.toByteArray();
+    inBuffer.reset();
+    return result;
+  }
+
+  byte[] lastUpdateDelegate() throws TransformerException
+  {
+    // process multiples of blocksize as much as possible
+    if (wired == Direction.FORWARD) // compressing
+      {
+        if (! compressor.finished())
+          {
+            compressor.finish();
+            while (! compressor.finished())
+              compress();
+          }
+      }
+    else // decompressing
+      {
+        if (! decompressor.finished())
+          {
+            IllegalStateException cause = new IllegalStateException(
+                "Compression transformer, after last update, must be finished "
+                + "but isn't");
+            throw new TransformerException("lastUpdateDelegate()", cause);
+          }
+      }
+    byte[] result = inBuffer.toByteArray();
+    inBuffer.reset();
+    return result;
+  }
+
+  private void compress()
+  {
+    int len = compressor.deflate(zlibBuffer);
+    if (len > 0)
+      inBuffer.write(zlibBuffer, 0, len);
+  }
+
+  private void decompress(byte[] in, int offset, int length)
+      throws TransformerException
+  {
+    decompressor.setInput(in, offset, length);
+    int len = 1;
+    while (len > 0)
+      {
+        try
+          {
+            len = decompressor.inflate(zlibBuffer);
+          }
+        catch (DataFormatException x)
+          {
+            throw new TransformerException("decompress()", x);
+          }
+        if (len > 0)
+          inBuffer.write(zlibBuffer, 0, len);
+      }
+  }
+}