GH-2387: Stop using Util.splitNamespaceXML. Reformat code.
diff --git a/jena-core/src/main/java/org/apache/jena/graph/Node_URI.java b/jena-core/src/main/java/org/apache/jena/graph/Node_URI.java
index 2f5c2c6..34c6ff1 100644
--- a/jena-core/src/main/java/org/apache/jena/graph/Node_URI.java
+++ b/jena-core/src/main/java/org/apache/jena/graph/Node_URI.java
@@ -20,8 +20,8 @@
 
 import java.util.Objects;
 
-import org.apache.jena.rdf.model.impl.Util ;
-import org.apache.jena.shared.* ;
+import org.apache.jena.shared.PrefixMapping;
+import org.apache.jena.util.SplitIRI;
 
 /**
     RDF nodes with a global identity given by a URI.
@@ -73,12 +73,12 @@
 
     @Override
     public String getNameSpace() {
-        return uriStr.substring(0, Util.splitNamespaceXML(uriStr));
+        return uriStr.substring(0, SplitIRI.splitXML(uriStr));
     }
 
     @Override
     public String getLocalName() {
-        return uriStr.substring(Util.splitNamespaceXML(uriStr));
+        return uriStr.substring(SplitIRI.splitXML(uriStr));
     }
 
     @Override
diff --git a/jena-core/src/main/java/org/apache/jena/rdf/model/impl/ModelCom.java b/jena-core/src/main/java/org/apache/jena/rdf/model/impl/ModelCom.java
index 9de0851..7d5602d 100644
--- a/jena-core/src/main/java/org/apache/jena/rdf/model/impl/ModelCom.java
+++ b/jena-core/src/main/java/org/apache/jena/rdf/model/impl/ModelCom.java
@@ -18,6 +18,8 @@
 
 package org.apache.jena.rdf.model.impl;
 
+import static org.apache.jena.shared.impl.PrefixMappingImpl.isNiceURI;
+
 import java.io.*;
 import java.net.URL;
 import java.util.*;
@@ -35,9 +37,9 @@
 import org.apache.jena.rdf.model.* ;
 import org.apache.jena.shared.* ;
 import org.apache.jena.shared.impl.JenaParameters;
-import org.apache.jena.shared.impl.PrefixMappingImpl ;
 import org.apache.jena.sys.JenaSystem ;
 import org.apache.jena.util.CollectionFactory ;
+import org.apache.jena.util.SplitIRI;
 import org.apache.jena.util.iterator.ClosableIterator;
 import org.apache.jena.util.iterator.ExtendedIterator;
 import org.apache.jena.util.iterator.FilterIterator;
@@ -830,7 +832,7 @@
             Node node = it.next();
             if ( node.isURI() ) {
                 String uri = node.getURI();
-                String ns = uri.substring(0, Util.splitNamespaceXML(uri));
+                String ns = uri.substring(0,  SplitIRI.splitXML(uri));
                 // String ns = IteratorFactory.asResource( node, this
                 // ).getNameSpace();
                 set.add(ns);
@@ -953,9 +955,10 @@
             Set<String> values = e.getValue();
             Set<String> niceValues = CollectionFactory.createHashedSet();
             for ( String uri : values ) {
-                if ( PrefixMappingImpl.isNiceURI(uri) ) {
+                @SuppressWarnings("deprecation")
+                boolean b = isNiceURI(uri);
+                if ( b )
                     niceValues.add(uri);
-                }
             }
             if ( niceValues.size() == 1 ) {
                 pm.setNsPrefix(key, niceValues.iterator().next());
diff --git a/jena-core/src/main/java/org/apache/jena/rdfxml/xmlinput0/JenaHandler.java b/jena-core/src/main/java/org/apache/jena/rdfxml/xmlinput0/JenaHandler.java
index 716a09a..feafcec 100644
--- a/jena-core/src/main/java/org/apache/jena/rdfxml/xmlinput0/JenaHandler.java
+++ b/jena-core/src/main/java/org/apache/jena/rdfxml/xmlinput0/JenaHandler.java
@@ -40,7 +40,7 @@
 
     public JenaHandler( Graph g, Model m, RDFErrorHandler e )
         { this( g, modelToPrefixMapping( m ), e ); }
-    
+
     private JenaHandler( Graph graph, RDFErrorHandler e )
         { this( graph, graph.getPrefixMapping(), e ); }
 
@@ -48,13 +48,13 @@
         {
         super( errorHandler );
         this.graph = graph ;
-        this.prefixMapping = prefixMapping; 
+        this.prefixMapping = prefixMapping;
         }
-    
+
     private static PrefixMapping modelToPrefixMapping( Model model )
         {
-        return model == null 
-            ? PrefixMapping.Factory.create() 
+        return model == null
+            ? PrefixMapping.Factory.create()
             : model.getGraph().getPrefixMapping()
             ;
         }
@@ -93,6 +93,7 @@
     }
 
     @Override
+    @SuppressWarnings("deprecation")
     public void startPrefixMapping( String prefix, String uri )
         {
         if (PrefixMappingImpl.isNiceURI( uri )) prefixMapping.setNsPrefix( prefix, uri );
diff --git a/jena-core/src/main/java/org/apache/jena/rdfxml/xmlinput1/JenaHandler.java b/jena-core/src/main/java/org/apache/jena/rdfxml/xmlinput1/JenaHandler.java
index 156a7b1..dd16ff8 100644
--- a/jena-core/src/main/java/org/apache/jena/rdfxml/xmlinput1/JenaHandler.java
+++ b/jena-core/src/main/java/org/apache/jena/rdfxml/xmlinput1/JenaHandler.java
@@ -90,6 +90,7 @@
     }
 
     @Override
+    @SuppressWarnings("deprecation")
     public void startPrefixMapping(String prefix, String uri) {
         if ( PrefixMappingImpl.isNiceURI(uri) )
             prefixMapping.setNsPrefix(prefix, uri);
diff --git a/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/RDFXMLWriterI.java b/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/RDFXMLWriterI.java
index 15e6937..164dc5a 100644
--- a/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/RDFXMLWriterI.java
+++ b/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/RDFXMLWriterI.java
@@ -28,8 +28,6 @@
  * set on RDF/XML and RDF/XML-ABBREV writers.
  */
 public interface RDFXMLWriterI extends RDFWriterI {
-    /** Suppress a compiler warning. */
-   Object _NotInteresting = RDFSyntax.parseCollection;
 
 /** Sets properties on this writer.
 
@@ -217,9 +215,6 @@
  * @return the old value for this property, or <code>null</code>
  * if no value was set.
  */
- @Override
-Object setProperty(
-    String propName,
-    Object propValue);
-
+    @Override
+    Object setProperty(String propName, Object propValue);
 }
diff --git a/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/BaseXMLWriter.java b/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/BaseXMLWriter.java
index a4f054b..f3c90e3 100644
--- a/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/BaseXMLWriter.java
+++ b/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/BaseXMLWriter.java
@@ -39,6 +39,7 @@
 import org.apache.jena.shared.* ;
 import org.apache.jena.util.CharEncoding ;
 import org.apache.jena.util.FileUtils ;
+import org.apache.jena.util.SplitIRI;
 import org.apache.jena.util.XMLChar;
 import org.apache.jena.vocabulary.* ;
 import org.slf4j.Logger ;
@@ -101,7 +102,18 @@
     abstract protected void writeBody
         ( Model mdl, PrintWriter pw, String baseUri, boolean inclXMLBase );
 
-	static private Set<String> badRDF = new HashSet<>();
+	static private Set<String> badRDF = Set.of("RDF",
+	                                           "Description",
+	                                           "li",
+	                                           "about",
+	                                           "aboutEach",
+	                                           "aboutEachPrefix",
+	                                           "ID",
+	                                           "nodeID",
+	                                           "parseType",
+	                                           "datatype",
+	                                           "bagID",
+	                                           "resource");
 
     /**
         Counter used for allocating Jena transient namespace declarations.
@@ -111,25 +123,7 @@
 	static String RDFNS = RDF.getURI();
 
 
-	static private Pattern jenaNamespace;
-
-	static {
-	    jenaNamespace =
-				Pattern.compile("j\\.([1-9][0-9]*|cook\\.up)");
-
-		badRDF.add("RDF");
-		badRDF.add("Description");
-		badRDF.add("li");
-		badRDF.add("about");
-		badRDF.add("aboutEach");
-		badRDF.add("aboutEachPrefix");
-		badRDF.add("ID");
-		badRDF.add("nodeID");
-		badRDF.add("parseType");
-		badRDF.add("datatype");
-		badRDF.add("bagID");
-		badRDF.add("resource");
-	}
+	static private final Pattern jenaNamespace = Pattern.compile("j\\.([1-9][0-9]*|cook\\.up)");
 
 	String xmlBase = null;
 
@@ -222,36 +216,30 @@
         while (nsIter.hasNext()) this.addNameSpace( nsIter.nextNs() );
     }
 
-    private void primeNamespace( Model model )
-    {
+    private void primeNamespace(Model model) {
         Map<String, String> m = model.getNsPrefixMap();
-        for ( Entry<String, String> e : m.entrySet() )
-        {
+        for ( Entry<String, String> e : m.entrySet() ) {
             String value = e.getValue();
-            String already = this.getPrefixFor( value );
-            if ( already == null )
-            {
-                this.setNsPrefix( model.getNsURIPrefix( value ), value );
-                if ( writingAllModelPrefixNamespaces )
-                {
-                    this.addNameSpace( value );
+            String already = this.getPrefixFor(value);
+            if ( already == null ) {
+                this.setNsPrefix(model.getNsURIPrefix(value), value);
+                if ( writingAllModelPrefixNamespaces ) {
+                    this.addNameSpace(value);
                 }
             }
         }
 
-        if ( usesPrefix(model, "") )
-        {
-            // Doing "" prefix.  Ensure it is a non-clashing, non-empty entity name.
-            String entityForEmptyPrefix = DEFAULT_NS_ENTITY_NAME ;
+        if ( usesPrefix(model, "") ) {
+            // Doing "" prefix. Ensure it is a non-clashing, non-empty entity name.
+            String entityForEmptyPrefix = DEFAULT_NS_ENTITY_NAME;
             if ( usesPrefix(model, entityForEmptyPrefix) )
-                entityForEmptyPrefix = DEFAULT_NS_ENTITY_NAME_ALT ;
-            int i = 0 ;
-            while ( usesPrefix(model,entityForEmptyPrefix) )
-            {
-                entityForEmptyPrefix = DEFAULT_NS_ENTITY_NAME_ALT+"."+i ;
-                i++ ;
+                entityForEmptyPrefix = DEFAULT_NS_ENTITY_NAME_ALT;
+            int i = 0;
+            while (usesPrefix(model, entityForEmptyPrefix)) {
+                entityForEmptyPrefix = DEFAULT_NS_ENTITY_NAME_ALT + "." + i;
+                i++;
             }
-            defaultNSEntityName = entityForEmptyPrefix ;
+            defaultNSEntityName = entityForEmptyPrefix;
         }
     }
 
@@ -287,40 +275,34 @@
     }
 
     private void setFromGivenNamespaces( Map<String, String> ns, Set<String> prefixesUsed ) {
-        for ( String uri : namespacesNeeded )
-        {
-            if ( ns.containsKey( uri ) )
-            {
+        for ( String uri : namespacesNeeded ) {
+            if ( ns.containsKey(uri) ) {
                 continue;
             }
             String val = null;
-            Set<String> s = nameSpaces.forward( uri );
-            if ( s != null )
-            {
+            Set<String> s = nameSpaces.forward(uri);
+            if ( s != null ) {
                 Iterator<String> it2 = s.iterator();
-                if ( it2.hasNext() )
-                {
+                if ( it2.hasNext() ) {
                     val = it2.next();
                 }
-                if ( prefixesUsed.contains( val ) )
-                {
+                if ( prefixesUsed.contains(val) ) {
                     val = null;
                 }
             }
-            if ( val == null )
-            {
-                // just in case the prefix has already been used, look for a free one.
-                // (the usual source of such prefixes is reading in a model we wrote out earlier)
-                do
-                {
-                    val = "j." + ( jenaPrefixCount++ );
-                }
-                while ( prefixesUsed.contains( val ) );
+            if ( val == null ) {
+                // just in case the prefix has already been used, look for a free
+                // one.
+                // (the usual source of such prefixes is reading in a model we wrote
+                // out earlier)
+                do {
+                    val = "j." + (jenaPrefixCount++);
+                } while (prefixesUsed.contains(val));
             }
-            ns.put( uri, val );
-            prefixesUsed.add( val );
+            ns.put(uri, val);
+            prefixesUsed.add(val);
         }
-	}
+    }
 
 	final synchronized public void setNsPrefix(String prefix, String ns) {
         if (checkLegalPrefix(prefix)) {
@@ -328,15 +310,14 @@
         }
     }
 
-    final public String getPrefixFor( String uri )
-        {
+    final public String getPrefixFor( String uri ) {
             // xml and xmlns namespaces are pre-bound
             if ("http://www.w3.org/XML/1998/namespace".equals(uri)) return "xml";
             if ("http://www.w3.org/2000/xmlns/".equals(uri)) return "xmlns";
         Set<String> s = nameSpaces.backward( uri );
         if (s != null && s.size() == 1) return s.iterator().next();
         return null;
-        }
+    }
 
 	String xmlnsDecl() {
 		workOutNamespaces();
@@ -392,13 +373,12 @@
 	}
 
 	String splitTag(String uriref, int type) {
-		int split = Util.splitNamespaceXML( uriref );
+		int split = SplitIRI.splitXML( uriref );
 		if (split == uriref.length()) throw new InvalidPropertyURIException( uriref );
 		return tag( uriref.substring( 0, split ), uriref.substring( split ), type, true );
     }
 
-	String tag( String namespace, String local, int type, boolean localIsQname)  {
-		String prefix = ns.get( namespace );
+	String tag( String namespace, String local, int type, boolean localIsQname) {
 		if (type != FAST && type != FASTATTR) {
 			if ((!localIsQname) && !XMLChar.isValidNCName(local))
 				return splitTag(namespace + local, type);
@@ -411,14 +391,12 @@
 				}
 			}
 		}
+        String prefix = ns.get( namespace );
 		boolean cookUp = false;
 		if (prefix == null) {
             checkURI( namespace );
-			logger.warn(
-				"Internal error: unexpected QName URI: <"
-					+ namespace
-					+ ">.  Fixing up with j.cook.up code.",
-				new BrokenException( "unexpected QName URI " + namespace ));
+            logger.warn("Internal error: unexpected QName URI: <" + namespace + ">.  Fixing up.",
+        				new BrokenException( "unexpected QName URI " + namespace ));
 			cookUp = true;
 		} else if (prefix.length() == 0) {
 			if (type == ATTR || type == FASTATTR)
@@ -430,8 +408,7 @@
 		return prefix + ":" + local;
 	}
 
-    private String cookUpAttribution( int type, String namespace, String local )
-        {
+    private String cookUpAttribution( int type, String namespace, String local ) {
         String prefix = "j.cook.up";
         switch (type) {
             case FASTATTR :
@@ -445,8 +422,8 @@
             case FAST :
               //  logger.error("Unreachable code - reached.");
                 throw new BrokenException( "cookup reached final FAST" );
-            }
         }
+    }
 
 	/** Write out an XML serialization of a model.
 	 * @param model the model to be serialized
@@ -455,37 +432,36 @@
 	 */
 	@Override
     final public void write(Model model, OutputStream out, String base)
-		 { write( model, FileUtils.asUTF8(out), base ); }
+	{ write( model, FileUtils.asUTF8(out), base ); }
 
 	/** Serialize Model <code>model</code> to Writer <code>out</code>.
      * @param model The model to be written.
 	 * @param out The Writer to which the serialization should be sent.
 	 * @param base the base URI for relative URI calculations.  <code>null</code> means use only absolute URI's.
 	 */
-	@Override
-    synchronized public void write(Model model, Writer out, String base)
-		 {
-		setupNamespaces( model );
-		PrintWriter pw = out instanceof PrintWriter ? (PrintWriter) out : new PrintWriter( out );
-		if (!Boolean.FALSE.equals(showXmlDeclaration)) writeXMLDeclaration( out, pw );
-		writeXMLBody( model, pw, base );
-		pw.flush();
-	}
+    @Override
+    synchronized public void write(Model model, Writer out, String base) {
+        setupNamespaces(model);
+        PrintWriter pw = out instanceof PrintWriter ? (PrintWriter)out : new PrintWriter(out);
+        if ( !Boolean.FALSE.equals(showXmlDeclaration) )
+            writeXMLDeclaration(out, pw);
+        writeXMLBody(model, pw, base);
+        pw.flush();
+    }
 
     /**
      	@param baseModel
      	@param model
     */
-    private void setupNamespaces( Model model )
-        {
+    private void setupNamespaces(Model model) {
         this.namespacesNeeded = new HashSet<>();
         this.ns = null;
         this.modelPrefixMapping = model;
-        primeNamespace( model );
-        addNameSpace( RDF.getURI() );
+        primeNamespace(model);
+        addNameSpace(RDF.getURI());
         addNameSpaces(model);
         jenaPrefixCount = 0;
-        }
+    }
 
 	private void writeXMLBody( Model model, PrintWriter pw, String base ) {
         if (showDoctypeDeclaration.booleanValue())
@@ -503,63 +479,55 @@
 	protected static final Pattern predefinedEntityNames = Pattern.compile( "amp|lt|gt|apos|quot" );
 
     public boolean isPredefinedEntityName( String name )
-        { return predefinedEntityNames.matcher( name ).matches(); }
+    { return predefinedEntityNames.matcher( name ).matches(); }
 
     private String attributeQuoteChar ="\"";
 
     protected String attributeQuoted( String s )
-        { return attributeQuoteChar + s + attributeQuoteChar; }
+    { return attributeQuoteChar + s + attributeQuoteChar; }
 
-    protected String substitutedAttribute( String s )
-        {
+    protected String substitutedAttribute( String s ) {
         String substituted = Util.substituteStandardEntities( s );
         if (!showDoctypeDeclaration.booleanValue())
             return attributeQuoted( substituted );
-        else
-            {
-            int split = Util.splitNamespaceXML( substituted );
+        else {
+            int split = SplitIRI.splitXML( substituted );
             String namespace = substituted.substring(  0, split );
             String prefix = modelPrefixMapping.getNsURIPrefix( namespace );
             return prefix == null || isPredefinedEntityName( prefix )
                 ? attributeQuoted( substituted )
                 : attributeQuoted( "&" + strForPrefix(prefix) + ";" + substituted.substring( split ) )
                 ;
-            }
         }
+    }
 
-    private void generateDoctypeDeclaration( Model model, PrintWriter pw )
-        {
+    private void generateDoctypeDeclaration( Model model, PrintWriter pw ) {
         String rdfns = RDF.getURI();
-		String rdfRDF = model.qnameFor( rdfns + "RDF" );
+        String rdfRDF = model.qnameFor( rdfns + "RDF" );
         if ( rdfRDF == null ) {
-        	model.setNsPrefix("rdf",rdfns);
-        	rdfRDF = "rdf:RDF";
+            model.setNsPrefix("rdf",rdfns);
+            rdfRDF = "rdf:RDF";
         }
         Map<String, String> prefixes = model.getNsPrefixMap();
         pw.print( "<!DOCTYPE " + rdfRDF +" [" );
-            for ( String prefix : prefixes.keySet() )
-            {
-                if ( isPredefinedEntityName( prefix ) )
-                {
-                    continue;
-                }
-                pw.print(
-                    newline + "  <!ENTITY " + strForPrefix( prefix ) + " '" + Util.substituteEntitiesInEntityValue(
-                        prefixes.get( prefix ) ) + "'>" );
-            }
-        pw.print( "]>" + newline );
+        for ( String prefix : prefixes.keySet() ) {
+            if ( isPredefinedEntityName( prefix ) )
+                continue;
+            pw.print(newline
+                     + "  <!ENTITY " + strForPrefix( prefix ) + " '" + Util.substituteEntitiesInEntityValue(prefixes.get( prefix ) )
+                     + "'>" );
         }
-
-	private String strForPrefix(String prefix)
-    {
-        if ( prefix.length() == 0 )
-            return defaultNSEntityName ;
-        return prefix ;
+        pw.print( "]>" + newline );
     }
 
-	private static boolean usesPrefix(Model model, String prefix)
-	{
-	    return model.getNsPrefixURI(prefix) != null ;
+    private String strForPrefix(String prefix) {
+        if ( prefix.length() == 0 )
+            return defaultNSEntityName;
+        return prefix;
+    }
+
+    private static boolean usesPrefix(Model model, String prefix) {
+        return model.getNsPrefixURI(prefix) != null;
     }
 
     private void writeXMLDeclaration(Writer out, PrintWriter pw) {
@@ -711,19 +679,17 @@
 		return result;
 	}
 
-    private String setShowDoctypeDeclaration( Object propValue )
-        {
+    private String setShowDoctypeDeclaration(Object propValue) {
         String oldValue = showDoctypeDeclaration.toString();
         showDoctypeDeclaration = getBooleanValue( propValue, Boolean.FALSE );
         return oldValue;
         }
 
-    private String setShowXmlDeclaration( Object propValue )
-        {
+    private String setShowXmlDeclaration( Object propValue ) {
         String oldValue = showXmlDeclaration == null ? null : showXmlDeclaration.toString();
         showXmlDeclaration = getBooleanValue( propValue, null );
         return oldValue;
-        }
+    }
 
     /**
         Answer the boolean value corresponding to o, which must either be a Boolean,
@@ -732,8 +698,7 @@
     static private boolean getBoolean( Object o )
         { return getBooleanValue( o, Boolean.FALSE ).booleanValue(); }
 
-    private static Boolean getBooleanValue( Object propValue, Boolean theDefault )
-        {
+    private static Boolean getBooleanValue( Object propValue, Boolean theDefault ) {
         if (propValue == null)
             return theDefault;
         else if (propValue instanceof Boolean)
@@ -742,15 +707,14 @@
             return stringToBoolean( (String) propValue, theDefault );
         else
             throw new JenaException( "cannot treat as boolean: " + propValue );
-        }
+    }
 
-	private static Boolean stringToBoolean( String b, Boolean theDefault )
-        {
+	private static Boolean stringToBoolean( String b, Boolean theDefault ) {
         if (b.equals( "default" )) return theDefault;
         if (b.equalsIgnoreCase( "true" )) return Boolean.TRUE;
         if (b.equalsIgnoreCase( "false" )) return Boolean.FALSE;
         throw new BadBooleanException( b );
-        }
+	}
 
 	Resource[] setTypes( Resource x[] ) {
 		logger.warn( "prettyTypes is not a property on the Basic RDF/XML writer." );
diff --git a/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/RDFXML_Basic.java b/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/RDFXML_Basic.java
index 14385c1..a6b85da 100644
--- a/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/RDFXML_Basic.java
+++ b/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/RDFXML_Basic.java
@@ -106,9 +106,7 @@
 			writeLiteral((Literal) object, writer);
 			writer.println(
 				"</"
-					+ endElementTag(
-						predicate.getNameSpace(),
-						predicate.getLocalName())
+					+ endElementTag(predicate.getNameSpace(), predicate.getLocalName())
 					+ ">");
 		}
 	}
diff --git a/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/Unparser.java b/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/Unparser.java
index 0b2b71e..50722fc 100644
--- a/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/Unparser.java
+++ b/jena-core/src/main/java/org/apache/jena/rdfxml/xmloutput/impl/Unparser.java
@@ -127,6 +127,7 @@
 import org.apache.jena.shared.BrokenException ;
 import org.apache.jena.shared.JenaException ;
 import org.apache.jena.shared.PropertyNotFoundException ;
+import org.apache.jena.util.SplitIRI;
 import org.apache.jena.util.XMLChar;
 import org.apache.jena.util.iterator.* ;
 import org.apache.jena.vocabulary.RDF ;
@@ -1178,9 +1179,8 @@
             throw new BrokenException("Internal error: getNameSpace(bNode)");
         }
         String uri = r.getURI();
-        int split = Util.splitNamespaceXML(uri);
+        int split = SplitIRI.splitXML(uri);
         return uri.substring(0, split);
-
     }
 
     /**
@@ -1215,7 +1215,7 @@
             throw new BrokenException("Internal error: getLocalName(bNode)");
         }
         String uri = r.getURI();
-        int split = Util.splitNamespaceXML(uri);
+        int split = SplitIRI.splitXML(uri);
         return uri.substring(split);
 
     }
@@ -1497,10 +1497,9 @@
         // Only allow resources with namespace and fragment ID
         String uri = ((Resource) n).getURI();
 
-        int split = Util.splitNamespaceXML(uri);
+        int split = SplitIRI.splitXML(uri);
         if (split == 0 || split == uri.length())
             return -1;
-
         return split;
     }
 
diff --git a/jena-core/src/main/java/org/apache/jena/shared/impl/PrefixMappingImpl.java b/jena-core/src/main/java/org/apache/jena/shared/impl/PrefixMappingImpl.java
index 4819812..7ec8555 100644
--- a/jena-core/src/main/java/org/apache/jena/shared/impl/PrefixMappingImpl.java
+++ b/jena-core/src/main/java/org/apache/jena/shared/impl/PrefixMappingImpl.java
@@ -24,9 +24,9 @@
 import java.util.Map.Entry;
 import java.util.concurrent.ConcurrentHashMap;
 
-import org.apache.jena.rdf.model.impl.Util ;
 import org.apache.jena.shared.PrefixMapping ;
 import org.apache.jena.util.CollectionFactory ;
+import org.apache.jena.util.SplitIRI;
 import org.apache.jena.util.XMLChar;
 
 /**
@@ -126,9 +126,10 @@
     }
 
     /**
-     * Test whether a URI is "nice" for RDF/XML (ends in a non NCName character).
+     * Test whether a URI is "nice" for RDF/XML (ends in a non-NCName character).
+     * @deprecated To be removed.
      */
-
+    @Deprecated
     public static boolean isNiceURI(String uri) {
         if ( uri.equals("") )
             return false;
@@ -226,28 +227,25 @@
      * Relies on <code>splitNamespace</code> to carve uri into namespace and
      * localname components; this ensures that the localname is legal and we just
      * have to (reverse-)lookup the namespace in the prefix table.
-     *
-     * @see org.apache.jena.shared.PrefixMapping#qnameFor(java.lang.String)
      */
     @Override
     public String qnameFor(String uri) {
-        int split = Util.splitNamespaceXML(uri);
-        String ns = uri.substring(0, split), local = uri.substring(split);
-        if ( local.equals("") )
+        int split = SplitIRI.splitXML(uri);
+        if ( split == uri.length() )
             return null;
+        String ns = uri.substring(0, split);
+        String local = uri.substring(split);
         String prefix = URItoPrefix.get(ns);
         return prefix == null ? null : prefix + ":" + local;
     }
 
     /**
-     * Compress the URI using the prefix mapping. This version of the code looks
-     * through all the maplets and checks each candidate prefix URI for being a
-     * leading substring of the argument URI. There's probably a much more efficient
-     * algorithm available, preprocessing the prefix strings into some kind of search
-     * table, but for the moment we don't need it.
+     * Compress the URI using the prefix mapping.
      */
     @Override
     public String shortForm(String uri) {
+        // This version of the code looks through all the maplets and checks each
+        // candidate prefix URI for being a leading substring of the argument URI.
         Entry<String, String> e = findMapping(uri, true);
         return e == null ? uri : e.getKey() + ":" + uri.substring((e.getValue()).length());
     }
diff --git a/jena-core/src/test/java/org/apache/jena/graph/test/TestNode.java b/jena-core/src/test/java/org/apache/jena/graph/test/TestNode.java
index a26adaa..554fc1b 100644
--- a/jena-core/src/test/java/org/apache/jena/graph/test/TestNode.java
+++ b/jena-core/src/test/java/org/apache/jena/graph/test/TestNode.java
@@ -20,7 +20,6 @@
 
 
 import junit.framework.TestSuite ;
-
 import org.apache.jena.atlas.lib.Creator;
 import org.apache.jena.datatypes.RDFDatatype ;
 import org.apache.jena.datatypes.TypeMapper ;
@@ -28,9 +27,9 @@
 import org.apache.jena.graph.* ;
 import org.apache.jena.graph.impl.LiteralLabel ;
 import org.apache.jena.graph.impl.LiteralLabelFactory ;
-import org.apache.jena.rdf.model.impl.Util ;
 import org.apache.jena.shared.JenaException ;
 import org.apache.jena.shared.PrefixMapping ;
+import org.apache.jena.util.SplitIRI;
 import org.apache.jena.vocabulary.* ;
 
 /**
@@ -714,7 +713,7 @@
     {
         for ( String uri : someURIs )
         {
-            int split = Util.splitNamespaceXML( uri );
+            int split = SplitIRI.splitXML( uri );
             Node n = NodeCreateUtils.create( uri );
             assertEquals( "check namespace", uri.substring( 0, split ), n.getNameSpace() );
             assertEquals( "check localname", uri.substring( split ), n.getLocalName() );
diff --git a/jena-core/src/test/java/org/apache/jena/util/TestSplitIRI_XML.java b/jena-core/src/test/java/org/apache/jena/util/TestSplitIRI_XML.java
index a00b919..525d43a 100644
--- a/jena-core/src/test/java/org/apache/jena/util/TestSplitIRI_XML.java
+++ b/jena-core/src/test/java/org/apache/jena/util/TestSplitIRI_XML.java
@@ -18,10 +18,11 @@
 
 package org.apache.jena.util;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
 import junit.framework.JUnit4TestAdapter;
-import org.apache.jena.rdf.model.impl.Util ;
 import org.junit.Test;
-import static org.junit.Assert.*;
 
 /**
  * Tests of splitting with RDF/XML rules, where the local name is more restricted
@@ -33,110 +34,108 @@
 public class TestSplitIRI_XML
 {
      public static junit.framework.Test suite() {
-         return new JUnit4TestAdapter(TestSplitIRI_XML.class) ;
+         return new JUnit4TestAdapter(TestSplitIRI_XML.class);
      }
 
     @Test public void splitNS_01()
-    { split("http://example/xyz", "http://example/", "xyz") ; }
+    { split("http://example/xyz", "http://example/", "xyz"); }
 
     @Test public void splitNS_02()
-    { split("http://example/ns#xyz", "http://example/ns#", "xyz") ; }
+    { split("http://example/ns#xyz", "http://example/ns#", "xyz"); }
 
     @Test public void splitNS_03()
-    { no_split("http://example/ns#") ; }
+    { no_split("http://example/ns#"); }
 
     @Test public void splitNS_04()
-    { no_split("http://example/") ; }
+    { no_split("http://example/"); }
 
     @Test public void splitNS_05()  // Illegal URI
-    { split("http://example", "http://", "example") ; }
+    { split("http://example", "http://", "example"); }
 
     @Test public void splitNS_06()   // localname must be at least the NCStartChar - not empty
-    { split("mailto:me", "mailto:m", "e") ; }
+    { split("mailto:me", "mailto:m", "e"); }
 
     @Test public void splitNS_07()
-    { split("urn:abc:xyz","urn:abc:", "xyz") ; }
+    { split("urn:abc:xyz","urn:abc:", "xyz"); }
 
     @Test public void splitNS_08()
-    { no_split("urn:abc:xyz:") ; }
+    { no_split("urn:abc:xyz:"); }
 
     @Test public void splitNS_09()
-    { split("http://bio2rdf.org/pdb:Pentane-3%2C4-diol-5-phosphate", "http://bio2rdf.org/pdb:Pentane-3%2C4-", "diol-5-phosphate") ; }
+    { split("http://bio2rdf.org/pdb:Pentane-3%2C4-diol-5-phosphate", "http://bio2rdf.org/pdb:Pentane-3%2C4-", "diol-5-phosphate"); }
 
     @Test public void splitNS_10()
-    { split("http://bio2rdf.org/pdb:Pentane-3,4-diol-5-phosphate", "http://bio2rdf.org/pdb:Pentane-3,4-", "diol-5-phosphate") ; }
+    { split("http://bio2rdf.org/pdb:Pentane-3,4-diol-5-phosphate", "http://bio2rdf.org/pdb:Pentane-3,4-", "diol-5-phosphate"); }
 
     // Don't split inside a %encoding.
     @Test public void splitNS_11()
-    { split("http://host/abc%AAdef", "http://host/abc%AA", "def") ; }
+    { split("http://host/abc%AAdef", "http://host/abc%AA", "def"); }
 
     @Test public void splitNS_12()
-    { split("http://host/abc%1Adef", "http://host/abc%1A", "def") ; }
+    { split("http://host/abc%1Adef", "http://host/abc%1A", "def"); }
 
     @Test public void splitNS_13()
-    { split("http://host/abc%A1def", "http://host/abc%A1", "def") ; }
+    { split("http://host/abc%A1def", "http://host/abc%A1", "def"); }
 
     @Test public void splitNS_14()
-    { split("http://host/abc%AA22def", "http://host/abc%AA22", "def") ; }
+    { split("http://host/abc%AA22def", "http://host/abc%AA22", "def"); }
 
     @Test public void splitNS_15()
-    { no_split("http://host/abc%AA22") ; }
+    { no_split("http://host/abc%AA22"); }
 
     // Other schemes
 
     @Test public void splitNS_50()
-    { split("file:///x/y", "file:///x/", "y") ; }
+    { split("file:///x/y", "file:///x/", "y"); }
 
     @Test public void splitNS_51()
-    { split("file:///x", "file:///", "x") ; }
+    { split("file:///x", "file:///", "x"); }
 
     @Test public void splitNS_52()
-    { split("file:x", "file:", "x") ; }
+    { split("file:x", "file:", "x"); }
 
     @Test public void splitNS_53()
     // Not ideal but some URI schemes dislike a URI with just the scheme
-    { split("file:foo", "file:", "foo") ; }
+    { split("file:foo", "file:", "foo"); }
 
     @Test public void splitNS_54()
-    { split("file:c:/foo", "file:c:/", "foo") ; }
+    { split("file:c:/foo", "file:c:/", "foo"); }
 
     // urn:uuid:d871c7f4-2926-11b2-8073-a5e169788449 - legal type 1 uuid as urn
     // uuid:3cf3e43a-3a5d-40d8-a93c-8697b162a1c0 - legal type 4 uuid as uri
 
     @Test public void splitNS_55()
-    { split("urn:uuid:d871c7f4-2926-11b2-8073-a5e169788449", "urn:uuid:", "d871c7f4-2926-11b2-8073-a5e169788449") ; }
+    { split("urn:uuid:d871c7f4-2926-11b2-8073-a5e169788449", "urn:uuid:", "d871c7f4-2926-11b2-8073-a5e169788449"); }
 
     @Test public void splitNS_56()
-    { split("uuid:3cf3e43a-3a5d-40d8-a93c-8697b162a1c0", "uuid:3", "cf3e43a-3a5d-40d8-a93c-8697b162a1c0") ; }
+    { split("uuid:3cf3e43a-3a5d-40d8-a93c-8697b162a1c0", "uuid:3", "cf3e43a-3a5d-40d8-a93c-8697b162a1c0"); }
 
     @Test public void splitNS_57()
-    { split("urn:abc:def", "urn:abc:", "def") ; }
+    { split("urn:abc:def", "urn:abc:", "def"); }
 
     // --------
 
     static void  no_split(String string)
-    { split(string, null, null) ; }
+    { split(string, null, null); }
 
-    static void split(String uriStr, String namespace, String localname)
-    {
+    static void split(String uriStr, String namespace, String localname) {
         if ( namespace == null && localname != null )
-            fail("Bad test - namespace is null but local name is not") ;
+            fail("Bad test - namespace is null but local name is not");
         if ( namespace != null && localname == null )
-            fail("Bad test - namespace is not null but local name is") ;
+            fail("Bad test - namespace is not null but local name is");
 
-        int idx = Util.splitNamespaceXML(uriStr) ;
-        if ( idx == uriStr.length() )
-        {
+        int idx = SplitIRI.splitXML(uriStr);
+        if ( idx == uriStr.length() ) {
             // No split.
             if ( namespace != null )
-                fail("Expected a split ("+namespace+","+localname+") - but none found") ;
-            return ;
+                fail("Expected a split (" + namespace + "," + localname + ") - but none found");
+            return;
 
         }
         // Split
-        String ns = uriStr.substring(0,idx) ;
-        String ln = uriStr.substring(idx) ;
-        assertEquals(namespace, ns) ;
-        assertEquals(localname, ln) ;
+        String ns = uriStr.substring(0, idx);
+        String ln = uriStr.substring(idx);
+        assertEquals(namespace, ns);
+        assertEquals(localname, ln);
     }
 }