diff --git a/README.md b/README.md
index 66f39d2..e1399b4 100644
--- a/README.md
+++ b/README.md
@@ -7,4 +7,4 @@
 
 The codebase for the active modules is in git:
 
-https://git-wip-us.apache.org/repos/asf?p=jena.git
+https://github.com/apache/jena
diff --git a/jena-base/src/main/java/org/apache/jena/atlas/io/IO.java b/jena-base/src/main/java/org/apache/jena/atlas/io/IO.java
index d22f5c3..d01ddf2 100644
--- a/jena-base/src/main/java/org/apache/jena/atlas/io/IO.java
+++ b/jena-base/src/main/java/org/apache/jena/atlas/io/IO.java
@@ -85,7 +85,7 @@
         if ( filename.startsWith("file:") )
         {
             filename = filename.substring("file:".length());
-            filename = IRILib.decode(filename);
+            filename = IRILib.decodeHex(filename);
         }
         InputStream in = new FileInputStream(filename);
         String ext = FilenameUtils.getExtension(filename);
@@ -180,7 +180,7 @@
         if ( filename.startsWith("file:") )
         {
             filename = filename.substring("file:".length());
-            filename = IRILib.decode(filename);
+            filename = IRILib.decodeHex(filename);
         }
         OutputStream out = new FileOutputStream(filename);
         String ext = FilenameUtils.getExtension(filename);
diff --git a/jena-base/src/main/java/org/apache/jena/atlas/lib/IRILib.java b/jena-base/src/main/java/org/apache/jena/atlas/lib/IRILib.java
index ffe05de..8c6dfff 100644
--- a/jena-base/src/main/java/org/apache/jena/atlas/lib/IRILib.java
+++ b/jena-base/src/main/java/org/apache/jena/atlas/lib/IRILib.java
@@ -232,10 +232,6 @@
         return uri ;
     }
 
-    public static String decode(String string) {
-        return StrUtils.decodeHex(string, '%') ;
-    }
-
     public static String encodeNonASCII(String string) {
         if ( ! containsNonASCII(string) )
             return string ;
@@ -248,7 +244,7 @@
                 sw.append( (char) b );
                 continue;
             }
-
+    
             int hi = ( b & 0xF0 ) >> 4;
             int lo = b & 0xF;
             sw.append( '%' );
@@ -265,5 +261,24 @@
                 return true;
         }
         return false ;
+    }
+
+    /** @deprecated Use {@link #decodeHex} */ 
+    @Deprecated
+    public static String decode(String string) { return decodeHex(string); }
+
+    /**
+     * Decode a string that may have %-encoded sequences.
+     * <p>
+     * This function will reverse 
+     * {@link #encodeNonASCII(String)},
+     * {@link #encodeUriPath(String)},
+     * {@link #encodeFileURL(String)} and
+     * {@link #encodeUriComponent(String)}.
+     * 
+     * It will not decode '+' used for space (application/x-www-form-urlencoded). 
+     */ 
+    public static String decodeHex(String string) {
+        return StrUtils.decodeHex(string, '%') ;
     } 
 }
diff --git a/jena-base/src/main/java/org/apache/jena/atlas/lib/StrUtils.java b/jena-base/src/main/java/org/apache/jena/atlas/lib/StrUtils.java
index f179bd3..796a7ca 100644
--- a/jena-base/src/main/java/org/apache/jena/atlas/lib/StrUtils.java
+++ b/jena-base/src/main/java/org/apache/jena/atlas/lib/StrUtils.java
@@ -22,6 +22,7 @@
 import static java.util.Arrays.stream ;
 import static java.util.stream.Collectors.toList;
 
+import java.nio.charset.StandardCharsets;
 import java.util.List;
 import java.util.Map;
 import java.util.Objects;
@@ -200,33 +201,38 @@
     /**
      * Decode a string using marked hex values e.g. %20
      * 
-     * @param str String to decode
-     * @param marker The marker charcater
+     * @param str String to decode : characters should be ASCII (<127)
+     * @param marker The marker character
      * @return Decoded string (returns input object on no change)
      */
     public static String decodeHex(String str, char marker) {
-        int idx = str.indexOf(marker);
-        if ( idx == -1 )
+        if ( str.indexOf(marker) < 0 ) 
             return str;
-        StringBuilder buff = new StringBuilder();
-
-        buff.append(str, 0, idx);
-        int N = str.length();
-
-        for ( ; idx < N ; idx++ ) {
-            char ch = str.charAt(idx);
-            // First time through this is true, always.
-            if ( ch != marker )
-                buff.append(ch);
-            else {
-                char hi = str.charAt(idx + 1);
-                char lo = str.charAt(idx + 2);
-                char ch2 = (char)(hexDecode(hi) << 4 | hexDecode(lo));
-                buff.append(ch2);
-                idx += 2;
+        // This function does work if input str is not pure ASCII.
+        // The tricky part is if an %-encoded part is a UTF-8 sequence.
+        // An alternative algorithm is to work in chars from the string, and handle
+        // that case %-endocded when value has the high bit set.
+        byte[] strBytes = StrUtils.asUTF8bytes(str);
+        final int N = strBytes.length;
+        // Max length
+        byte[] bytes = new byte[strBytes.length];
+        int i = 0;
+        for ( int j = 0 ; j < N ; j++ ) {
+            byte b = strBytes[j];
+            if ( b != marker ) {
+                bytes[i++] = b;
+                continue;
             }
+            // Marker.
+            char hi = str.charAt(j + 1);
+            char lo = str.charAt(j + 2);
+            j += 2;
+            int x1 = hexDecode(hi);
+            int x2 = hexDecode(lo);
+            int ch2 = (hexDecode(hi) << 4 | hexDecode(lo));
+            bytes[i++] = (byte)ch2;
         }
-        return buff.toString();
+        return new String(bytes, 0, i, StandardCharsets.UTF_8); 
     }
 
     // Encoding is table-driven but for decode, we use code.
diff --git a/jena-base/src/test/java/org/apache/jena/atlas/lib/TS_Lib.java b/jena-base/src/test/java/org/apache/jena/atlas/lib/TS_Lib.java
index b05d47c..87abe6e 100644
--- a/jena-base/src/test/java/org/apache/jena/atlas/lib/TS_Lib.java
+++ b/jena-base/src/test/java/org/apache/jena/atlas/lib/TS_Lib.java
@@ -41,6 +41,7 @@
     , TestCache2.class
     , TestFileOps.class
     , TestStrUtils.class
+    , TestIRILib.class
     , TestXMLLib.class
     , TestAlarmClock.class
     , TestTrie.class
diff --git a/jena-base/src/test/java/org/apache/jena/atlas/lib/TestIRILib.java b/jena-base/src/test/java/org/apache/jena/atlas/lib/TestIRILib.java
new file mode 100644
index 0000000..cd11e22
--- /dev/null
+++ b/jena-base/src/test/java/org/apache/jena/atlas/lib/TestIRILib.java
@@ -0,0 +1,44 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.atlas.lib;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Test;
+
+public class TestIRILib {
+
+    @Test public void encodeDecode01() { encodeDecode(""); }
+
+    @Test public void encodeDecode02() { encodeDecode("aa"); }
+
+    @Test public void encodeDecode03() { encodeDecode("aa"); }
+
+    @Test public void encodeDecode04() { encodeDecode("Größe"); }
+    
+    private void encodeDecode(String testString) {
+        String encoded = IRILib.encodeNonASCII(testString);
+        String decoded = IRILib.decodeHex(encoded);
+        if ( ! testString.equals(decoded) ) {
+            System.out.println(encoded);
+        }
+        assertEquals(testString, decoded);
+    }
+
+}
diff --git a/jena-db/jena-dboe-transaction/src/main/java/org/apache/jena/dboe/transaction/txn/TransactionInfo.java b/jena-db/jena-dboe-transaction/src/main/java/org/apache/jena/dboe/transaction/txn/TransactionInfo.java
index a727f85..d49698a 100644
--- a/jena-db/jena-dboe-transaction/src/main/java/org/apache/jena/dboe/transaction/txn/TransactionInfo.java
+++ b/jena-db/jena-dboe-transaction/src/main/java/org/apache/jena/dboe/transaction/txn/TransactionInfo.java
@@ -63,7 +63,7 @@
      */
     public ReadWrite getMode();
 
-    /** Is this currently a READ transaction? Promotion may chnage the mode.
+    /** Is this currently a READ transaction? Promotion may change the mode.
      * Convenience operation equivalent to {@code (getMode() == ReadWrite.READ)}
      */
     public default boolean isReadTxn()  { return getMode() == ReadWrite.READ; }
@@ -81,4 +81,3 @@
     }
 
 }
-
diff --git a/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/params/StoreParams.java b/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/params/StoreParams.java
index b2a851a..d62d8dd 100644
--- a/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/params/StoreParams.java
+++ b/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/params/StoreParams.java
@@ -30,10 +30,10 @@
  * and some parameters can only be changed at the point the database is
  * created.
  * <p>
- * Getting paramters settings wrong can destroy a databse.
+ * Getting parameters settings wrong can destroy a databse.
  * Alternating the block size is not encouraged and should only be
  * done if necessary.  It can silently destroy a database if set
- * to a different value than thatused to create the database.  The
+ * to a different value than that used to create the database.  The
  * default value of 8Kbytes is good for almost use.
  *
  * @see StoreParamsBuilder  for constructing StoreParams
diff --git a/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/TDB2StorageBuilder.java b/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/TDB2StorageBuilder.java
index 18b76cd..5648afe 100644
--- a/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/TDB2StorageBuilder.java
+++ b/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/TDB2StorageBuilder.java
@@ -62,9 +62,9 @@
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-/** Build TDB2 databases based on {@linkplain DatabaseRDF}. 
+/** Build TDB2 databases based on {@linkplain DatabaseRDF}.
  * This builds the storage database, not the switchable.
- * 
+ *
  * {@link DatabaseOps#createSwitchable} adds the switching layer
  * and is called by {@link DatabaseConnection#make}.
  */
@@ -300,67 +300,15 @@
 
     private NodeTable buildNodeTable(String name) {
         NodeTable nodeTable = buildBaseNodeTable(name);
-        
+
         nodeTable = NodeTableCache.create(nodeTable, params);
-        
+
         if ( nodeTable instanceof NodeTableCache ) {
             NodeTableCache nodeTableCache = (NodeTableCache)nodeTable;
-            
-            // [1746] A "notification" - better way to do this?
-            // Need to go before the storage of the node table commits. 
-//            TransactionalComponent tc = new TransactionalComponentBase<Object>(ComponentId.allocLocal()) {
-//                
-//                private Object state = new Object();
-//                private TxnId activeWriter = null;
-//                
-//                @Override
-//                protected Object _begin(ReadWrite readWrite, TxnId txnId) {
-//                    System.out.println("_begin");
-////                    // XXX OK?
-////                    if ( isWriteTxn() ) {
-////                        nodeTableCache.updateBegin(txnId);
-////                        activeWriter = txnId;
-////                    }
-//                    return state;
-//                }
-//                
-//                @Override
-//                protected Object _promote(TxnId txnId, Object state) {
-//                    System.out.println("_promote");
-////                    if ( isWriteTxn() ) {
-////                        nodeTableCache.updateBegin(txnId);
-////                        activeWriter = txnId;
-////                    }
-//                    return state;
-//                }
-//                
-////                @Override
-////                protected void _commit(TxnId txnId, Object state) {}
-//
-//                @Override
-//                protected void _commitEnd(TxnId txnId, Object state) {
-//                    System.out.println("_commitEnd");
-////                    if ( activeWriter == txnId ) {
-////                        nodeTableCache.updateCommit();
-////                        activeWriter = null;
-////                    }
-//                }
-//
-//                @Override
-//                protected void _abort(TxnId txnId, Object state) {
-//                    System.out.println("_abort");
-////                    if ( activeWriter == txnId ) {
-////                        nodeTableCache.updateAbort();
-////                        activeWriter = null;
-////                    }
-//                }
-//            };
-//            components.add(tc);
 
-            // [1746]
             listeners.add(nodeTableCache);
         }
-        
+
         nodeTable = NodeTableInline.create(nodeTable);
         return nodeTable;
     }
@@ -384,7 +332,7 @@
         TransBinaryDataFile transBinFile = new TransBinaryDataFile(binFile, cid, pState);
         return transBinFile;
     }
-    
+
     private static boolean warnAboutOptimizer = true ;
     public static ReorderTransformation chooseReorderTransformation(Location location) {
         if ( location == null )
diff --git a/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/nodetable/NodeTableCache.java b/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/nodetable/NodeTableCache.java
index 0d3d7fd..aa02c25 100644
--- a/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/nodetable/NodeTableCache.java
+++ b/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/nodetable/NodeTableCache.java
@@ -41,25 +41,31 @@
  */
 public class NodeTableCache implements NodeTable, TransactionListener {
     // These caches are updated together.
-    // See synchronization in _retrieveNodeByNodeId and _idForNode
+    // See synchronization in _retrieveNodeByNodeId and _idForNode.
     // The cache is assumed to be single operation-thread-safe.
-
-    // The buffering is for updates. Only the updating thread will see changes due to new nodes
-    // Case 1: Not in main "not-present"
-    //  Add to local "not-present", flush down.
-
-    // Case 2: In main "not-present"
-    //   May be goes into local cache.
-    //   Write back updates "not-present"
-    //   Depends on "not-rpesent" used to protect the underlying "not-present"
-
-
+    // The buffering is for updates so that if it aborts, the changes are not made;
+    // the underlying node table, being transactional, also does not make the changes.
+    //
+    // It does not matter if a readers can see nodes from a completed now-finished
+    // writer transaction. Nodes in the node table do not mean triples exist and only triples detemine
+    // the state of the data.
+    //
+    // Where there are only readers active the ThreadBufferingCache caches act as
+    // pass-through and the not-present cache can be updated by any reader.
+    //
+    // When there is an active writer, the ThreadBufferingCache caches add a
+    // write-visible-only caching and only the writer can update the "not-present"
+    // cache. Because the node table is append-only (nodes are not deleted), it can
+    // mean a node which was not-present is added and the not-present cache now does
+    // not catch that for a previous version reader. This does not matter, the small
+    // not-present cache is only a speed-up and does not have to be correct
+    // for missing nodes (it can't have entries for nodes that do exist in visible
+    // data).
 
     private ThreadBufferingCache<Node, NodeId> node2id_Cache = null;
     private ThreadBufferingCache<NodeId, Node> id2node_Cache = null;
 
     // A small cache of "known unknowns" to speed up searching for impossible things.
-    // Cache update needed on NodeTable changes because a node may become "known"
     private Cache<Node, Object> notPresent    = null;
     private NodeTable           baseTable;
     private final Object        lock          = new Object();
@@ -297,14 +303,16 @@
             notPresent.remove(node);
     }
 
-    // A top-level transaction is either
+    // A top-level transaction can update the not-present cache.
+    // It is either
     // - a write transaction or
-    // - a read transaction with most recent data version given that there's no active write transaction.
+    // - a read transaction and no active writer.
     private boolean inTopLevelTxn() {
         Thread writer = writingThread;
         return (writer == null) || (writer == Thread.currentThread());
     }
 
+    // -- TransactionListener
     @Override
     public void notifyTxnStart(Transaction transaction) {
         if (transaction.isWriteTxn())
@@ -329,18 +337,17 @@
         if(transaction.isWriteTxn())
             updateAbort();
     }
-
-    // ----
+    // -- TransactionListener
 
     // The cache is "optimistic" - nodes are added during the transaction.
-    // It does not matter if they get added (and visible earlier)
-    // because this is nothing more than "preallocation". Triples (Tuple of NodeIds) don't match.
-
-    // Underlying file has them "transactionally".
-
+    // The underlying file has them "transactionally".
+    //
     // On abort, it does need to be undone because the underlying NodeTable
     // being cached will not have them.
-
+    //
+    // We don't "undo" for abort because it would mean keeping an data structure that
+    // is related to the size of the transaction and if in-memory, a limitation of
+    // scale.
     private void updateStart() {
         node2id_Cache.enableBuffering();
         id2node_Cache.enableBuffering();
@@ -383,6 +390,7 @@
         id2node_Cache = null;
         notPresent = null;
         baseTable = null;
+        writingThread = null;
     }
 
     @Override
diff --git a/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/nodetable/ThreadBufferingCache.java b/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/nodetable/ThreadBufferingCache.java
index e946e53..b683671 100644
--- a/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/nodetable/ThreadBufferingCache.java
+++ b/jena-db/jena-tdb2/src/main/java/org/apache/jena/tdb2/store/nodetable/ThreadBufferingCache.java
@@ -55,7 +55,7 @@
     private String label;
     // This turns the feature off. Development only. Do not release with this set "false".
     private static final boolean BUFFERING = true;
-    
+
     public ThreadBufferingCache(String label, Cache<Key,Value> mainCache, int size) {
         this.localCache = CacheFactory.createCache(size);
         this.baseCache = mainCache;
@@ -72,14 +72,13 @@
         return bufferingThread.get() == currentThread;
     }
 
-    // XXX [1746] Can replace by direct use.
     private Cache<Key, Value> localCache() {
         return localCache;
     }
 
     // ---- Buffer management.
     // Only one thread can be using the additional caches.
-    
+
     public void enableBuffering() {
         if ( ! BUFFERING )
             return;
@@ -89,7 +88,7 @@
             throw new TDBException(Lib.className(this)+": already buffering");
         }
     }
-    
+
     /** Write the local cache to the main cache, and reset the local cache. */
     public void flushBuffer() {
         if ( ! buffering() )
@@ -116,7 +115,7 @@
         localCache().clear();
         bufferingThread.set(null);
     }
-    
+
     public Cache<Key, Value> getBuffer() {
         return localCache();
     }
@@ -167,7 +166,7 @@
 
     // ---- Flush changes, reset.
 
-    
+
 
     // ---- Updates to buffering, local cache.
 
diff --git a/jena-fuseki2/jena-fuseki-core/src/main/java/org/apache/jena/fuseki/servlets/GSP_R.java b/jena-fuseki2/jena-fuseki-core/src/main/java/org/apache/jena/fuseki/servlets/GSP_R.java
index efef1f3..606ab0f 100644
--- a/jena-fuseki2/jena-fuseki-core/src/main/java/org/apache/jena/fuseki/servlets/GSP_R.java
+++ b/jena-fuseki2/jena-fuseki-core/src/main/java/org/apache/jena/fuseki/servlets/GSP_R.java
@@ -33,9 +33,9 @@
 import org.apache.jena.sparql.core.DatasetGraph;
 
 public class GSP_R extends GSP_Base {
-    
+
     public GSP_R() {}
-    
+
     @Override
     protected void doGet(HttpAction action) {
         if ( isQuads(action) )
@@ -45,6 +45,7 @@
     }
 
     protected void execGetQuads(HttpAction action) {
+        ActionLib.setCommonHeaders(action.response);
         MediaType mediaType = ActionLib.contentNegotationQuads(action);
         ServletOutputStream output;
         try { output = action.response.getOutputStream(); }
@@ -85,6 +86,7 @@
     }
 
     protected void execGetGSP(HttpAction action) {
+        ActionLib.setCommonHeaders(action.response);
         MediaType mediaType = ActionLib.contentNegotationRDF(action);
 
         ServletOutputStream output;
@@ -98,7 +100,6 @@
         if ( action.verbose )
             action.log.info(format("[%d]   Get: Content-Type=%s, Charset=%s => %s",
                             action.id, mediaType.getContentType(), mediaType.getCharset(), lang.getName()));
-        ActionLib.setCommonHeaders(action.response);
         try {
             DatasetGraph dsg = decideDataset(action);
             GSPTarget target = determineTarget(dsg, action);
@@ -141,23 +142,37 @@
 
     @Override
     protected void doHead(HttpAction action) {
-        action.beginRead();
+        if ( isQuads(action) )
+            execHeadQuads(action);
+        else
+            execHeadGSP(action);
+    }
+
+    protected void execHeadQuads(HttpAction action) {
         ActionLib.setCommonHeaders(action.response);
+        MediaType mediaType = ActionLib.contentNegotationQuads(action);
+        if ( action.verbose )
+            action.log.info(format("[%d]   Head: Content-Type=%s", action.id, mediaType.getContentType()));
+        ServletOps.success(action);
+    }
+
+    protected void execHeadGSP(HttpAction action) {
+        ActionLib.setCommonHeaders(action.response);
+        MediaType mediaType = ActionLib.contentNegotationRDF(action);
+        if ( action.verbose )
+            action.log.info(format("[%d]   Head: Content-Type=%s", action.id, mediaType.getContentType()));
+        // Check graph not 404.
+        action.beginRead();
         try {
             DatasetGraph dsg = decideDataset(action);
             GSPTarget target = determineTarget(dsg, action);
             if ( action.log.isDebugEnabled() )
-                action.log.debug("HEAD->" + target);
-            if ( !target.exists() ) {
-                ServletOps.successNotFound(action);
-                return;
-            }
-            MediaType mediaType = ActionLib.contentNegotationRDF(action);
+                action.log.debug("HEAD->"+target);
+            boolean exists = target.exists();
+            if ( ! exists )
+                ServletOps.errorNotFound("No such graph: <"+target.name+">");
             ServletOps.success(action);
-        }
-        finally {
-            action.endRead();
-        }
+        } finally { action.endRead(); }
     }
 
     @Override
diff --git a/jena-fuseki2/jena-fuseki-main/src/test/java/org/apache/jena/fuseki/main/TestHTTP.java b/jena-fuseki2/jena-fuseki-main/src/test/java/org/apache/jena/fuseki/main/TestHTTP.java
new file mode 100644
index 0000000..cceb07d
--- /dev/null
+++ b/jena-fuseki2/jena-fuseki-main/src/test/java/org/apache/jena/fuseki/main/TestHTTP.java
@@ -0,0 +1,161 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.fuseki.main;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+import org.apache.jena.atlas.lib.StrUtils;
+import org.apache.jena.atlas.web.WebLib;
+import org.apache.jena.graph.Graph;
+import org.apache.jena.query.Dataset;
+import org.apache.jena.query.DatasetFactory;
+import org.apache.jena.rdf.model.Model;
+import org.apache.jena.rdf.model.ModelFactory;
+import org.apache.jena.riot.Lang;
+import org.apache.jena.riot.web.HttpNames;
+import org.apache.jena.riot.web.HttpOp;
+import org.apache.jena.sparql.core.DatasetGraph;
+import org.apache.jena.sparql.core.DatasetGraphFactory;
+import org.apache.jena.sparql.sse.SSE;
+import org.junit.AfterClass;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+/** Test HTTP level details */
+public class TestHTTP {
+    private static FusekiServer server = null;
+    private static int port;
+
+    private static Model data;
+    private static Dataset dataset;
+
+    private static String URL;
+
+    @BeforeClass
+    public static void beforeClass() {
+        port = WebLib.choosePort();
+        URL = "http://localhost:" + port + "/ds";
+        Graph graph = SSE.parseGraph(StrUtils.strjoinNL
+            ("(graph"
+            ,"   (:s :p 1)"
+            ,")"));
+        data = ModelFactory.createModelForGraph(graph);
+
+        DatasetGraph dsgData = DatasetGraphFactory.create();
+        dsgData.add(SSE.parseQuad("(:g :s :p 2 )"));
+        dataset = DatasetFactory.wrap(dsgData);
+
+        DatasetGraph dsg = DatasetGraphFactory.createTxnMem();
+
+        FusekiServer server = FusekiServer.create()
+            .add("/ds", dsg)
+            .port(port)
+            .build();
+        server.start();
+    }
+
+    @AfterClass
+    public static void afterClass() {
+        if ( server != null )
+            server.stop();
+    }
+
+    // GET
+
+    @Test public void gspGet_dataset_1() {
+        // Base URL, default content type => N-Quads (dump format)
+        HttpOp.execHttpGet(URL, null, (base, response)->{
+            String h = response.getFirstHeader(HttpNames.hContentType).getValue();
+            assertNotNull(h);
+            assertEquals(Lang.NQUADS.getHeaderString(), h);
+        });
+    }
+
+
+    @Test public void gspGet_dataset_2() {
+        String ct = Lang.TRIG.getHeaderString();
+        HttpOp.execHttpGet(URL, ct, (base, response)->{
+            String h = response.getFirstHeader(HttpNames.hContentType).getValue();
+            assertNotNull(h);
+            assertEquals(ct, h);
+        });
+    }
+
+    @Test public void gspGet_graph_1() {
+        String target = URL+"?default";
+        HttpOp.execHttpGet(target, null, (base, response)->{
+            String h = response.getFirstHeader(HttpNames.hContentType).getValue();
+            assertNotNull(h);
+            // "Traditional default".
+            assertEquals(Lang.RDFXML.getHeaderString(), h);
+        });
+    }
+
+    @Test public void gspGet_graph_2() {
+        String target = URL+"?default";
+        String ct = Lang.TTL.getHeaderString();
+        HttpOp.execHttpGet(target, ct, (base, response)->{
+            String h = response.getFirstHeader(HttpNames.hContentType).getValue();
+            assertNotNull(h);
+            assertEquals(ct, h);
+        });
+    }
+
+    // HEAD
+
+    @Test public void gspHead_dataset_1() {
+        // Base URL, default content type => N-Quads (dump format)
+        HttpOp.execHttpHead(URL, null, (base, response)->{
+            String h = response.getFirstHeader(HttpNames.hContentType).getValue();
+            assertNotNull(h);
+            assertEquals(Lang.NQUADS.getHeaderString(), h);
+        });
+    }
+
+
+    @Test public void gspHead_dataset_2() {
+        String ct = Lang.TRIG.getHeaderString();
+        HttpOp.execHttpHead(URL, ct, (base, response)->{
+            String h = response.getFirstHeader(HttpNames.hContentType).getValue();
+            assertNotNull(h);
+            assertEquals(ct, h);
+        });
+    }
+
+    @Test public void gspHead_graph_1() {
+        String target = URL+"?default";
+        HttpOp.execHttpHead(target, null, (base, response)->{
+            String h = response.getFirstHeader(HttpNames.hContentType).getValue();
+            assertNotNull(h);
+            // "Traditional default".
+            assertEquals(Lang.RDFXML.getHeaderString(), h);
+        });
+    }
+
+    @Test public void gspHead_graph_2() {
+        String target = URL+"?default";
+        String ct = Lang.TTL.getHeaderString();
+        HttpOp.execHttpHead(target, ct, (base, response)->{
+            String h = response.getFirstHeader(HttpNames.hContentType).getValue();
+            assertNotNull(h);
+            assertEquals(ct, h);
+        });
+    }
+}
diff --git a/jena-fuseki2/jena-fuseki-webapp/src/main/java/org/apache/jena/fuseki/mgt/ActionDatasets.java b/jena-fuseki2/jena-fuseki-webapp/src/main/java/org/apache/jena/fuseki/mgt/ActionDatasets.java
index 1225718..3d5e3b8 100644
--- a/jena-fuseki2/jena-fuseki-webapp/src/main/java/org/apache/jena/fuseki/mgt/ActionDatasets.java
+++ b/jena-fuseki2/jena-fuseki-webapp/src/main/java/org/apache/jena/fuseki/mgt/ActionDatasets.java
@@ -27,11 +27,7 @@
 import java.io.StringReader;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.HashMap;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Locale;
-import java.util.Map;
+import java.util.*;
 
 import javax.servlet.http.HttpServletRequest;
 
@@ -66,11 +62,7 @@
 import org.apache.jena.query.Dataset;
 import org.apache.jena.query.ReadWrite;
 import org.apache.jena.rdf.model.*;
-import org.apache.jena.riot.Lang;
-import org.apache.jena.riot.RDFDataMgr;
-import org.apache.jena.riot.RDFLanguages;
-import org.apache.jena.riot.RDFParser;
-import org.apache.jena.riot.WebContent;
+import org.apache.jena.riot.*;
 import org.apache.jena.riot.system.StreamRDF;
 import org.apache.jena.riot.system.StreamRDFLib;
 import org.apache.jena.shared.uuid.JenaUUID;
@@ -82,6 +74,7 @@
 import org.apache.jena.update.UpdateAction;
 import org.apache.jena.update.UpdateFactory;
 import org.apache.jena.update.UpdateRequest;
+import org.apache.jena.vocabulary.RDF;
 import org.apache.jena.web.HttpSC;
 
 public class ActionDatasets extends ActionContainerItem {
@@ -169,21 +162,10 @@
                 RDFDataMgr.write(outCopy, model, Lang.TURTLE);
             }
             // ----
-
             // Process configuration.
-            Statement stmt = getOne(model, null, pServiceName, null);
-            if ( stmt == null ) {
-                StmtIterator sIter = model.listStatements(null, pServiceName, (RDFNode)null );
-                if ( ! sIter.hasNext() )
-                    ServletOps.errorBadRequest("No name given in description of Fuseki service");
-                sIter.next();
-                if ( sIter.hasNext() )
-                    ServletOps.errorBadRequest("Multiple names given in description of Fuseki service");
-                throw new InternalErrorException("Inconsistent: getOne didn't fail the second time");
-            }
 
-            if ( ! stmt.getObject().isLiteral() )
-                ServletOps.errorBadRequest("Found "+FmtUtils.stringForRDFNode(stmt.getObject())+" : Service names are strings, then used to build the external URI");
+            // Returns the "service fu:name NAME" statement
+            Statement stmt = findService(model);
 
             Resource subject = stmt.getSubject();
             Literal object = stmt.getObject().asLiteral();
@@ -255,6 +237,45 @@
         return null;
     }
 
+    /** Find the service resource. There must be only one in the configuration. */
+    private Statement findService(Model model) {
+        // Try to find by unique pServiceName (max backwards compatibility)
+        // then try to find by rdf:type fuseki:Service.
+
+        // JENA-1794
+        Statement stmt = getOne(model, null, pServiceName, null);
+        // null means 0 or many, not one.
+
+        if ( stmt == null ) {
+            // This calculates { ?x rdf:type fu:Service ; ?x fu:name ?name }
+            // One and only one service.
+            Statement stmt2 = getOne(model, null, RDF.type, FusekiVocab.fusekiService);
+            if ( stmt2 == null ) {
+                int count = model.listStatements(null, RDF.type, FusekiVocab.fusekiService).toList().size();
+                if ( count == 0 )
+                    ServletOps.errorBadRequest("No triple rdf:type fuseki:Service found");
+                else
+                    ServletOps.errorBadRequest("Multiple Fuseki service descriptions");
+            }
+            Statement stmt3 = getOne(model, stmt2.getSubject(), pServiceName, null);
+            if ( stmt3 == null ) {
+                StmtIterator sIter = model.listStatements(stmt2.getSubject(), pServiceName, (RDFNode)null );
+                if ( ! sIter.hasNext() )
+                    ServletOps.errorBadRequest("No name given in description of Fuseki service");
+                sIter.next();
+                if ( sIter.hasNext() )
+                    ServletOps.errorBadRequest("Multiple names given in description of Fuseki service");
+                throw new InternalErrorException("Inconsistent: getOne didn't fail the second time");
+            }
+            stmt = stmt3;
+        }
+
+        if ( ! stmt.getObject().isLiteral() )
+            ServletOps.errorBadRequest("Found "+FmtUtils.stringForRDFNode(stmt.getObject())+" : Service names are strings, then used to build the external URI");
+
+        return stmt;
+    }
+
     @Override
     protected JsonValue execPostItem(HttpAction action) {
         String name = getItemDatasetName(action);
@@ -312,7 +333,7 @@
         String name = getItemDatasetName(action);
         if ( name == null )
             name = "";
-        action.log.info(format("[%d] DELETE ds=%s", action.id, name));
+        action.log.info(format("[%d] DELETE dataset=%s", action.id, name));
 
         if ( ! action.getDataAccessPointRegistry().isRegistered(name) )
             ServletOps.errorNotFound("No such dataset registered: "+name);
diff --git a/jena-fuseki2/jena-fuseki-webapp/src/test/java/org/apache/jena/fuseki/TestAdmin.java b/jena-fuseki2/jena-fuseki-webapp/src/test/java/org/apache/jena/fuseki/TestAdmin.java
index e29f90d..7516fa6 100644
--- a/jena-fuseki2/jena-fuseki-webapp/src/test/java/org/apache/jena/fuseki/TestAdmin.java
+++ b/jena-fuseki2/jena-fuseki-webapp/src/test/java/org/apache/jena/fuseki/TestAdmin.java
@@ -55,7 +55,7 @@
 public class TestAdmin extends AbstractFusekiTest {
 
     // Name of the dataset in the assembler file.
-    static String dsTest    = "test-ds2";
+    static String dsTest    = "test-ds1";
     static String dsTestInf = "test-ds4";
     static String fileBase  = "testing/";
 
@@ -133,7 +133,7 @@
     @Test public void add_delete_dataset_2() {
         checkNotThere(dsTest);
 
-        File f = new File(fileBase+"config-ds-plain.ttl");
+        File f = new File(fileBase+"config-ds-plain-1.ttl");
         {
             org.apache.http.entity.ContentType ct = org.apache.http.entity.ContentType.parse(WebContent.contentTypeTurtle+"; charset="+WebContent.charsetUTF8);
             HttpEntity e = new FileEntity(f, ct);
@@ -153,7 +153,7 @@
         deleteDataset(dsTest);
     }
 
-    @Test public void add_delete_dataset_3() throws Exception {
+    @Test public void add_delete_dataset_3() {
         checkNotThere(dsTest);
         addTestDataset();
         checkExists(dsTest);
@@ -164,7 +164,7 @@
         deleteDataset(dsTest);
     }
 
-    @Test public void add_delete_dataset_4() throws Exception {
+    @Test public void add_delete_dataset_4() {
         checkNotThere(dsTest);
         checkNotThere(dsTestInf);
         addTestDatasetInf();
@@ -178,6 +178,12 @@
         deleteDataset(dsTestInf);
     }
 
+    @Test public void add_delete_dataset_5() {
+        // New style operations : cause two fuseki:names
+        addTestDataset(fileBase+"config-ds-plain-2.ttl");
+        checkExists("test-ds2");
+    }
+
     @Test public void add_error_1() {
         FusekiTest.execWithHttpException(HttpSC.BAD_REQUEST_400,
                                          ()-> addTestDataset(fileBase+"config-ds-bad-name-1.ttl"));
@@ -354,7 +360,7 @@
     // -- Add
 
     private static void addTestDataset() {
-        addTestDataset(fileBase+"config-ds-plain.ttl");
+        addTestDataset(fileBase+"config-ds-plain-1.ttl");
     }
 
     private static void addTestDatasetInf() {
diff --git a/jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain.ttl b/jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain-1.ttl
similarity index 72%
rename from jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain.ttl
rename to jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain-1.ttl
index aba5d82..f993f35 100644
--- a/jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain.ttl
+++ b/jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain-1.ttl
@@ -1,3 +1,5 @@
+## Licensed under the terms of http://www.apache.org/licenses/LICENSE-2.0
+
 PREFIX :        <#>
 PREFIX fuseki:  <http://jena.apache.org/fuseki#>
 PREFIX rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
@@ -5,9 +7,9 @@
 PREFIX rdfs:    <http://www.w3.org/2000/01/rdf-schema#>
 PREFIX ja:      <http://jena.hpl.hp.com/2005/11/Assembler#>
 
-<#service1> rdf:type fuseki:Service ;
+<#service1> #rdf:type fuseki:Service ;
     # URI of the dataset -- http://host:port/ds
-    fuseki:name                        "test-ds2" ; 
+    fuseki:name                        "test-ds1" ; 
     fuseki:serviceQuery                "sparql" ;
     fuseki:dataset                     <#emptyDataset> ;
     .
diff --git a/jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain-2.ttl b/jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain-2.ttl
new file mode 100644
index 0000000..d4b3fc9
--- /dev/null
+++ b/jena-fuseki2/jena-fuseki-webapp/testing/config-ds-plain-2.ttl
@@ -0,0 +1,18 @@
+## Licensed under the terms of http://www.apache.org/licenses/LICENSE-2.0
+
+PREFIX :        <#>
+PREFIX fuseki:  <http://jena.apache.org/fuseki#>
+PREFIX rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
+PREFIX rdfs:    <http://www.w3.org/2000/01/rdf-schema#>
+PREFIX ja:      <http://jena.hpl.hp.com/2005/11/Assembler#>
+
+<#service1> rdf:type fuseki:Service ;
+    fuseki:name                       "test-ds2" ; 
+    fuseki:endpoint [
+        fuseki:operation fuseki:query ; 
+        fuseki:name "sparql"
+    ] ;
+    fuseki:dataset                    <#emptyDataset> ;
+    .
+
+<#emptyDataset> rdf:type ja:MemoryDataset .
diff --git a/jena-shacl/src/main/java/org/apache/jena/shacl/validation/ValidationProc.java b/jena-shacl/src/main/java/org/apache/jena/shacl/validation/ValidationProc.java
index 12e1027..7c862fe 100644
--- a/jena-shacl/src/main/java/org/apache/jena/shacl/validation/ValidationProc.java
+++ b/jena-shacl/src/main/java/org/apache/jena/shacl/validation/ValidationProc.java
@@ -35,9 +35,7 @@
 import org.apache.jena.shacl.parser.PropertyShape;
 import org.apache.jena.shacl.parser.Shape;
 import org.apache.jena.sparql.path.Path;
-import org.apache.jena.vocabulary.RDF;
 
-import static org.apache.jena.shacl.lib.G.hasType;
 import static org.apache.jena.shacl.lib.G.isOfType;
 
 public class ValidationProc {
@@ -273,16 +271,14 @@
         Node targetObj = target.getObject();
         switch(target.getTargetType()) {
             case targetClass:
-                return G.listPO(data, RDF.Nodes.type, targetObj);
+            case implicitClass:
+                return G.listAllNodesOfType(data, targetObj);
             case targetNode:
                 return Collections.singletonList(targetObj);
             case targetObjectsOf:
                 return G.setSP(data, null, targetObj);
             case targetSubjectsOf:
                 return G.setPO(data, targetObj, null);
-            case implicitClass:
-                // Instances of the class and its subtypes.
-                return G.listAllNodesOfType(data, targetObj);
             default:
                 return Collections.emptyList();
         }
@@ -298,15 +294,14 @@
         Node targetObject = target.getObject();
         switch (target.getTargetType()) {
             case targetClass:
-                return hasType(data, node, targetObject);
+            case implicitClass:
+                return isOfType(data, node, targetObject);
             case targetNode:
                 return targetObject.equals(node);
             case targetObjectsOf:
                 return data.contains(null, targetObject, node);
             case targetSubjectsOf:
                 return data.contains(node, targetObject, null);
-            case implicitClass:
-                return isOfType(data, node, targetObject);
             default:
                 return false;
         }
diff --git a/jena-shacl/src/test/resources/local/additional/target-class-subclass-1.ttl b/jena-shacl/src/test/resources/local/additional/target-class-subclass-1.ttl
new file mode 100644
index 0000000..f0c668e
--- /dev/null
+++ b/jena-shacl/src/test/resources/local/additional/target-class-subclass-1.ttl
@@ -0,0 +1,51 @@
+PREFIX ex:       <http://example/>
+
+PREFIX rdf:     <http://www.w3.org/1999/02/22-rdf-syntax-ns#> 
+PREFIX rdfs:    <http://www.w3.org/2000/01/rdf-schema#>
+
+PREFIX sh:      <http://www.w3.org/ns/shacl#>
+PREFIX xsd:     <http://www.w3.org/2001/XMLSchema#>
+
+PREFIX sht:     <http://www.w3.org/ns/shacl-test#>
+PREFIX mf:      <http://www.w3.org/2001/sw/DataAccess/tests/test-manifest#>
+
+ex:A rdf:type rdfs:Class .
+
+ex:B #rdf:type rdfs:Class ;
+     rdfs:subClassOf ex:A .
+     
+ex:x rdf:type ex:B .
+
+ex:ShapeDef
+    rdf:type sh:NodeShape ;
+    sh:targetClass ex:A;
+    sh:property [
+        sh:path rdfs:label ;
+        sh:minCount 1 ;
+    ] .
+
+<>
+  rdf:type mf:Manifest ;
+  mf:entries ( <target-class-subclass-1> )
+  .
+
+<target-class-subclass-1>
+  rdf:type sht:Validate ;
+  rdfs:label "Instance of implicit class target and subclass test" ;
+  mf:action [
+      sht:dataGraph <> ;
+      sht:shapesGraph <> ;
+    ] ;
+  mf:result [
+      rdf:type     sh:ValidationReport ;
+      sh:conforms  false ;
+      sh:result [
+          rdf:type           sh:ValidationResult ;
+          sh:focusNode       ex:x ;
+          sh:resultMessage              "minCount[1]: Invalid cardinality: expected min 1: Got count = 0" ;
+          sh:resultPath                 rdfs:label ;
+          sh:resultSeverity             sh:Violation ;
+          sh:sourceConstraintComponent  sh:MinCountConstraintComponent ;
+          sh:sourceShape                [] 
+      ]
+    ] .
diff --git a/jena-shacl/src/test/resources/local/manifest.ttl b/jena-shacl/src/test/resources/local/manifest.ttl
index bb465b6..45479b7 100644
--- a/jena-shacl/src/test/resources/local/manifest.ttl
+++ b/jena-shacl/src/test/resources/local/manifest.ttl
@@ -11,4 +11,5 @@
   rdf:type mf:Manifest ;
   mf:include <additional/lang-simple-1.ttl> ;
   mf:include <additional/implicit-subclass-1.ttl> ;
+  mf:include <additional/target-class-subclass-1.ttl> ;
 .