Add save extra namespaces

src/main/java/org/apache/xmlbeans/XmlOptions.java

@@ -107,6 +107,7 @@ public enum XmlOptionsKeys {
         SAVE_CDATA_LENGTH_THRESHOLD,
         SAVE_CDATA_ENTITY_COUNT_THRESHOLD,
         SAVE_SAX_NO_NSDECLS_IN_ATTRIBUTES,
+        SAVE_EXTRA_NAMESPACES,
         LOAD_REPLACE_DOCUMENT_ELEMENT,
         LOAD_STRIP_WHITESPACE,
         LOAD_STRIP_COMMENTS,
@@ -448,6 +449,23 @@ public Map<String, String> getSaveSuggestedPrefixes() {
         return (Map<String, String>) get(XmlOptionsKeys.SAVE_SUGGESTED_PREFIXES);
     }
 
+    /**
+     * A map of hints to pass to the saver for which prefixes to use
+     * for which namespace URI.
+     *
+     * @param extraNamespaces a map from URIs to prefixes
+     * @see XmlTokenSource#save(java.io.File, XmlOptions)
+     * @see XmlTokenSource#xmlText(XmlOptions)
+     */
+    public XmlOptions setSaveExtraNamespaces(Map<String, String> extraNamespaces) {
+        return set(XmlOptionsKeys.SAVE_EXTRA_NAMESPACES, extraNamespaces);
+    }
+
+    @SuppressWarnings("unchecked")
+    public Map<String, String> getSaveExtraNamespaces() {
+        return (Map<String, String>) get(XmlOptionsKeys.SAVE_EXTRA_NAMESPACES);
+    }
+
     /**
      * This option causes the saver to filter a Processing Instruction
      * with the given target

src/main/java/org/apache/xmlbeans/impl/store/Saver.java

@@ -46,6 +46,9 @@ abstract class Saver {
 
     private SaveCur _cur;
 
+    protected boolean _isTopLevelElement = true;
+    protected final Map<String, String> _extraNamespaces;
+
     private List<String> _ancestorNamespaces;
     private final Map<String, String> _suggestedPrefixes;
     protected XmlOptionCharEscapeMap _replaceChar;
@@ -135,6 +138,8 @@ protected void syntheticNamespace(String prefix, String uri, boolean considerDef
         _suggestedPrefixes = options.getSaveSuggestedPrefixes();
 
         _ancestorNamespaces = _cur.getAncestorNamespaces();
+
+        _extraNamespaces = options.getSaveExtraNamespaces();
     }
 
     private static SaveCur createSaveCur(Cur c, XmlOptions options) {
@@ -287,10 +292,12 @@ protected final boolean process() {
         switch (_cur.kind()) {
             case ROOT: {
                 processRoot();
+                _isTopLevelElement = true;
                 break;
             }
             case ELEM: {
                 processElement();
+                _isTopLevelElement = false;
                 break;
             }
             case -ELEM: {
@@ -899,6 +906,8 @@ protected boolean emitElement(SaveCur c, List<QName> attrNames, List<String> att
                 emitNamespacesHelper();
             }
 
+            emitExtraNamespacesHelper();
+
             for (int i = 0; i < attrNames.size(); i++) {
                 emitAttrHelper(attrNames.get(i), attrValues.get(i));
             }
@@ -943,6 +952,17 @@ protected void emitXmlns(String prefix, String uri) {
             emit('"');
         }
 
+        private void emitExtraNamespacesHelper() {
+            if (!_isTopLevelElement || null == _extraNamespaces)
+                return;
+
+            for (Map.Entry<String, String> nsEntry : _extraNamespaces.entrySet()) {
+                emit(' ');
+                emitXmlns(nsEntry.getKey(), nsEntry.getValue());
+            }
+
+        }
+
         private void emitNamespacesHelper() {
             LinkedHashMap<String, String> nsMap = new LinkedHashMap<>();
             for (iterateMappings(); hasMapping(); nextMapping()) {
@@ -1853,6 +1873,8 @@ protected boolean emitElement(SaveCur c, List<QName> attrNames, List<String> att
             emit('<');
             emitName(c.getName(), false);
 
+            emitExtraNamespacesHelper();
+
             for (int i = 0; i < attrNames.size(); i++) {
                 emitAttrHelper(attrNames.get(i), attrValues.get(i));
             }
@@ -1902,6 +1924,15 @@ private void emitNamespacesHelper() {
             }
         }
 
+        private void emitExtraNamespacesHelper() {
+            if (!_isTopLevelElement || null == _extraNamespaces)
+                return;
+            for (Map.Entry<String, String> nsEntry : _extraNamespaces.entrySet()) {
+                emit(' ');
+                emitXmlns(nsEntry.getKey(), nsEntry.getValue());
+            }
+        }
+
         private void emitAttrHelper(QName attrName, String attrValue) {
             emit(' ');
             emitName(attrName, true);
@@ -2578,6 +2609,15 @@ private String getPrefixedName(QName name) {
             return prefix + ":" + local;
         }
 
+        private void emitExtraNamespacesHelper() {
+            if (!_isTopLevelElement || null == _extraNamespaces|| !_nsAsAttrs)
+                return;
+            for (Map.Entry<String, String> nsEntry : _extraNamespaces.entrySet()) {
+                String prefix = nsEntry.getKey();
+                _attributes.addAttribute("http://www.w3.org/2000/xmlns/", prefix, "xmlns:" + prefix , "CDATA", nsEntry.getValue());
+            }
+        }
+
         private void emitNamespacesHelper() {
             for (iterateMappings(); hasMapping(); nextMapping()) {
                 String prefix = mappingPrefix();
@@ -2607,6 +2647,8 @@ protected boolean emitElement(SaveCur c, List<QName> attrNames, List<String> att
                 emitNamespacesHelper();
             }
 
+            emitExtraNamespacesHelper();
+
             for (int i = 0; i < attrNames.size(); i++) {
                 QName name = attrNames.get(i);