Fix issues around XMLStreamWriter based on the isRepairingNamespaces property of XMLOutputFactory

More refactoring to use common-xml and common-java

git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@803742 13f79535-47bb-0310-9956-ffa450edef68

6 files changed, 44 insertions, 479 deletions

diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/BaseStAXArtifactProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/BaseStAXArtifactProcessor.java
index 5f7095f80a..a11a69867b 100644
--- a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/BaseStAXArtifactProcessor.java
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/BaseStAXArtifactProcessor.java
@@ -22,16 +22,11 @@ package org.apache.tuscany.sca.contribution.processor;
 import static javax.xml.stream.XMLStreamConstants.END_ELEMENT;
 import static javax.xml.stream.XMLStreamConstants.START_ELEMENT;
 
-import java.util.ArrayList;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.List;
-import java.util.StringTokenizer;
 
-import javax.xml.XMLConstants;
 import javax.xml.namespace.NamespaceContext;
 import javax.xml.namespace.QName;
-import javax.xml.stream.XMLStreamConstants;
 import javax.xml.stream.XMLStreamException;
 import javax.xml.stream.XMLStreamReader;
 import javax.xml.stream.XMLStreamWriter;
@@ -39,6 +34,7 @@ import javax.xml.stream.XMLStreamWriter;
 import org.apache.tuscany.sca.assembly.AssemblyFactory;
 import org.apache.tuscany.sca.assembly.Extensible;
 import org.apache.tuscany.sca.assembly.Extension;
+import org.apache.tuscany.sca.common.xml.stax.StAXHelper;
 
 
 /**
@@ -47,7 +43,10 @@ import org.apache.tuscany.sca.assembly.Extension;
  * @version $Rev$ $Date$
  */
 public abstract class BaseStAXArtifactProcessor {
-
+    /**
+     * The StAXHelper without states
+     */
+    private static final StAXHelper helper = new StAXHelper(null, null, null);
     /**
      * Returns a QName from a string.
      * @param reader
@@ -55,18 +54,7 @@ public abstract class BaseStAXArtifactProcessor {
      * @return
      */
     protected QName getQNameValue(XMLStreamReader reader, String value) {
-        if (value != null) {
-            int index = value.indexOf(':');
-            String prefix = index == -1 ? "" : value.substring(0, index);
-            String localName = index == -1 ? value : value.substring(index + 1);
-            String ns = reader.getNamespaceContext().getNamespaceURI(prefix);
-            if (ns == null) {
-                ns = "";
-            }
-            return new QName(ns, localName, prefix);
-        } else {
-            return null;
-        }
+        return StAXHelper.getValueAsQName(reader, value);
     }
 
     /**
@@ -76,11 +64,12 @@ public abstract class BaseStAXArtifactProcessor {
      * @return
      */
     protected boolean getBoolean(XMLStreamReader reader, String name) {
-        String value = reader.getAttributeValue(null, name);
-        if (value == null) {
+        Boolean attr = StAXHelper.getAttributeAsBoolean(reader, name);
+        if (attr == null) {
             return false;
+        } else {
+            return attr.booleanValue();
         }
-        return Boolean.valueOf(value);
     }
 
     /**
@@ -90,8 +79,7 @@ public abstract class BaseStAXArtifactProcessor {
      * @return
      */
     protected QName getQName(XMLStreamReader reader, String name) {
-        String qname = reader.getAttributeValue(null, name);
-        return getQNameValue(reader, qname);
+        return StAXHelper.getAttributeAsQName(reader, name);
     }
 
     /**
@@ -101,16 +89,7 @@ public abstract class BaseStAXArtifactProcessor {
      * @return
      */
     protected List<QName> getQNames(XMLStreamReader reader, String name) {
-        String value = reader.getAttributeValue(null, name);
-        if (value != null) {
-            List<QName> qnames = new ArrayList<QName>();
-            for (StringTokenizer tokens = new StringTokenizer(value); tokens.hasMoreTokens();) {
-                qnames.add(getQNameValue(reader, tokens.nextToken()));
-            }
-            return qnames;
-        } else {
-            return Collections.emptyList();
-        }
+        return StAXHelper.getAttributeAsQNames(reader, name);
     }
 
     /**
@@ -120,7 +99,7 @@ public abstract class BaseStAXArtifactProcessor {
      * @return
      */
     protected String getString(XMLStreamReader reader, String name) {
-        return reader.getAttributeValue(null, name);
+        return StAXHelper.getAttributeAsString(reader, name);
     }
 
     /**
@@ -130,7 +109,7 @@ public abstract class BaseStAXArtifactProcessor {
      * @return
      */
     protected boolean isSet(XMLStreamReader reader, String name) {
-        return reader.getAttributeValue(null, name) != null;
+        return StAXHelper.isAttributePresent(reader, name);
     }
 
     /**
@@ -140,8 +119,7 @@ public abstract class BaseStAXArtifactProcessor {
      *         returned.
      */
     protected QName getXSIType(XMLStreamReader reader) {
-        String qname = reader.getAttributeValue(XMLConstants.W3C_XML_SCHEMA_INSTANCE_NS_URI, "type");
-        return getQNameValue(reader, qname);
+        return StAXHelper.getXSIType(reader);
     }
 
     /**
@@ -170,18 +148,7 @@ public abstract class BaseStAXArtifactProcessor {
      * @throws XMLStreamException if there was a problem reading the stream
      */
     protected void skipToEndElement(XMLStreamReader reader) throws XMLStreamException {
-        int depth = 0;
-        while (reader.hasNext()) {
-            int event = reader.next();
-            if (event == XMLStreamConstants.START_ELEMENT) {
-                depth++;
-            } else if (event == XMLStreamConstants.END_ELEMENT) {
-                if (depth == 0) {
-                    return;
-                }
-                depth--;
-            }
-        }
+        StAXHelper.skipToEndElement(reader);
     }
 
     /**
@@ -220,17 +187,9 @@ public abstract class BaseStAXArtifactProcessor {
      * @param attrs
      * @throws XMLStreamException
      */
-    protected void writeStart(XMLStreamWriter writer, String uri, String name, XAttr... attrs) throws XMLStreamException {
-//        String prefix = setPrefix(writer, uri);
-        writer.writeStartElement(uri, name);
-
-        // [rfeng] When the XMLStreamWriter is in the repairing namespace mode, we should not try to write namespace
-        // as it will create duplicate namespace declarations
-        
-//        if (prefix != null){
-//             writer.writeNamespace(prefix,uri);
-//        }
-        writeAttributePrefixes(writer, attrs);
+    protected void writeStart(XMLStreamWriter writer, String uri, String name, XAttr... attrs)
+        throws XMLStreamException {
+        helper.writeStartElement(writer, "", name, uri);
         writeAttributes(writer, attrs);
     }
 
@@ -299,19 +258,6 @@ public abstract class BaseStAXArtifactProcessor {
     }
 
     /**
-     * Write attribute prefixes to the current element.
-     * @param writer
-     * @param attrs
-     * @throws XMLStreamException
-     */
-    protected void writeAttributePrefixes(XMLStreamWriter writer, XAttr... attrs) throws XMLStreamException {
-        for (XAttr attr : attrs) {
-            if (attr != null)
-                attr.writePrefix(writer);
-        }
-    }
-
-    /**
      *
      * @param reader
      * @param elementName
@@ -457,6 +403,10 @@ public abstract class BaseStAXArtifactProcessor {
         public XAttr(String name, QName value) {
             this(null, name, value);
         }
+        
+        public String toString() {
+            return uri == null ? name + "=\"" + value + "\"" : "{" + uri + "}" + name + "=\"" + value + "\"";
+        }
 
         /**
          * Writes a string from a QName and registers a prefix for its namespace.
@@ -466,66 +416,14 @@ public abstract class BaseStAXArtifactProcessor {
          */
         private String writeQNameValue(XMLStreamWriter writer, QName qname) throws XMLStreamException {
             if (qname != null) {
-                String prefix = qname.getPrefix();
-                String uri = qname.getNamespaceURI();
-                prefix = writer.getPrefix(uri);
-                if (prefix != null) {
-
-                    // Use the prefix already bound to the given URI
-                    if (prefix.length() > 0) {
-                        return prefix + ":" + qname.getLocalPart();
-                    } else {
-
-                        // Empty prefix, just return the local part of the given qname
-                        return qname.getLocalPart();
-                    }
-
+                String prefix = helper.writeNamespace(writer, qname.getPrefix(), qname.getNamespaceURI());
+                if ("".equals(prefix)) {
+                    return qname.getLocalPart();
                 } else {
-
-                    // Find an available prefix and bind it to the given URI
-                    NamespaceContext nsc = writer.getNamespaceContext();
-                    for (int i=1; ; i++) {
-                        prefix = "ns" + i;
-                        if (nsc.getNamespaceURI(prefix) == null) {
-                            break;
-                        }
-                    }
-                    writer.setPrefix(prefix, uri);
-                    writer.writeNamespace(prefix, uri);
                     return prefix + ":" + qname.getLocalPart();
                 }
-            } else {
-                return null;
-            }
-        }
-
-        /**
-         * Registers a prefix for the namespace of a QName.
-         * @param reader
-         * @param value
-         * @return
-         */
-        private void writeQNamePrefix(XMLStreamWriter writer, QName qname) throws XMLStreamException {
-            if (qname != null) {
-                String prefix = qname.getPrefix();
-                String uri = qname.getNamespaceURI();
-                prefix = writer.getPrefix(uri);
-                if (prefix != null) {
-                    return;
-                } else {
-
-                    // Find an available prefix and bind it to the given URI
-                    NamespaceContext nsc = writer.getNamespaceContext();
-                    for (int i=1; ; i++) {
-                        prefix = "ns" + i;
-                        if (nsc.getNamespaceURI(prefix) == null) {
-                            break;
-                        }
-                    }
-                    writer.setPrefix(prefix, uri);
-                    writer.writeNamespace(prefix, uri);
-                }
             }
+            return null;
         }
 
         /**
@@ -585,39 +483,7 @@ public abstract class BaseStAXArtifactProcessor {
                 return;
             }
 
-            // Write the attribute
-            if (uri != null && !uri.equals(SCA11_NS)) {
-                writer.writeAttribute(uri, name, str);
-            } else {
-                writer.writeAttribute(name,str);
-            }
-        }
-
-        /**
-         * Registers a prefix for the namespace of a QName or list of QNames
-         * @param writer
-         * @throws XMLStreamException
-         */
-        public void writePrefix(XMLStreamWriter writer) throws XMLStreamException {
-            if (value instanceof QName) {
-
-                // Write prefix for a single QName value
-                writeQNamePrefix(writer, (QName)value);
-
-            } else if (value instanceof Collection) {
-
-                // Write prefixes for a list of values
-                for (Object v: (Collection<?>)value) {
-                    if (v instanceof QName) {
-                        // Write prefix for a QName value
-                        writeQNamePrefix(writer, (QName)v);
-
-                    } else if (v instanceof XAttr) {
-                        // Write prefix for an XAttr value
-                        ((XAttr)v).writePrefix(writer);
-                    }
-                }
-            }
+            helper.writeAttribute(writer, "", name, uri, str);
         }
     }
 
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/impl/ContributionInfoProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/impl/ContributionInfoProcessor.java
index eb1946c4b8..2bb6b59e57 100644
--- a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/impl/ContributionInfoProcessor.java
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/impl/ContributionInfoProcessor.java
@@ -24,10 +24,10 @@ import java.io.InputStream;
 import java.net.URI;
 import java.net.URISyntaxException;
 import java.net.URL;
-import java.net.URLConnection;
 import java.util.List;
 
 import org.apache.tuscany.sca.assembly.Composite;
+import org.apache.tuscany.sca.common.java.io.IOHelper;
 import org.apache.tuscany.sca.contribution.Contribution;
 import org.apache.tuscany.sca.contribution.ContributionFactory;
 import org.apache.tuscany.sca.contribution.ContributionMetadata;
@@ -128,9 +128,7 @@ public class ContributionInfoProcessor implements URLArtifactProcessor<Contribut
             URL url = scanner.getArtifactURL(contribution, path);
             try {
                 // Check if the file actually exists before trying to read it
-                URLConnection connection = url.openConnection();
-                connection.setUseCaches(false);
-                InputStream is = connection.getInputStream();
+                InputStream is = IOHelper.openStream(url);
                 is.close();
             } catch (IOException e) {
                 continue;
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/xml/AnyElementProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/xml/AnyElementProcessor.java
index 02618c489b..931a0bce4a 100644
--- a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/xml/AnyElementProcessor.java
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/xml/AnyElementProcessor.java
@@ -19,22 +19,21 @@
 package org.apache.tuscany.sca.contribution.processor.xml;
 
 import java.io.StringReader;
-import java.io.StringWriter;
 
 import javax.xml.namespace.QName;
-import javax.xml.stream.XMLInputFactory;
-import javax.xml.stream.XMLOutputFactory;
 import javax.xml.stream.XMLStreamException;
 import javax.xml.stream.XMLStreamReader;
 import javax.xml.stream.XMLStreamWriter;
 
 import org.apache.tuscany.sca.assembly.AssemblyFactory;
 import org.apache.tuscany.sca.assembly.Extension;
+import org.apache.tuscany.sca.common.xml.stax.StAXHelper;
 import org.apache.tuscany.sca.contribution.Constants;
 import org.apache.tuscany.sca.contribution.processor.ContributionReadException;
 import org.apache.tuscany.sca.contribution.processor.ContributionResolveException;
 import org.apache.tuscany.sca.contribution.processor.StAXArtifactProcessor;
 import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
 import org.apache.tuscany.sca.core.FactoryExtensionPoint;
 import org.apache.tuscany.sca.monitor.Monitor;
 
@@ -42,17 +41,16 @@ public class AnyElementProcessor implements StAXArtifactProcessor<Extension> {
     private static final QName ANY_ELEMENT = new QName(Constants.XMLSCHEMA_NS, "any");
 
     private AssemblyFactory assemblyFactory;
-    private XMLInputFactory xmlInputFactory;
-    private XMLOutputFactory xmlOutputFactory;
+    private StAXHelper helper;
     
     @SuppressWarnings("unused")
     private Monitor monitor;
 
 
-    public AnyElementProcessor(FactoryExtensionPoint modelFactories, Monitor monitor) {
+    public AnyElementProcessor(ExtensionPointRegistry extensionPoints, StAXArtifactProcessor<Object> extensionProcessor, Monitor monitor) {
+        FactoryExtensionPoint modelFactories = extensionPoints.getExtensionPoint(FactoryExtensionPoint.class);
         assemblyFactory = modelFactories.getFactory(AssemblyFactory.class);
-        xmlInputFactory = modelFactories.getFactory(XMLInputFactory.class);
-        xmlOutputFactory = modelFactories.getFactory(XMLOutputFactory.class);
+        this.helper = StAXHelper.getInstance(extensionPoints);
         this.monitor = monitor;
     }
 
@@ -74,15 +72,10 @@ public class AnyElementProcessor implements StAXArtifactProcessor<Extension> {
      */
     public Extension read(XMLStreamReader reader) throws ContributionReadException, XMLStreamException {
         QName name = reader.getName();
-        XMLStreamSerializer serializer = new XMLStreamSerializer();
-        StringWriter sw = new StringWriter();
-        XMLStreamWriter writer = xmlOutputFactory.createXMLStreamWriter(sw);
-        serializer.serialize(reader, writer);
-        writer.flush();
-        
+        String xml = helper.saveAsString(reader);
         Extension ext = assemblyFactory.createExtension();
         ext.setQName(name);
-        ext.setValue(sw.toString());
+        ext.setValue(xml);
         
         return ext;
     }
@@ -99,11 +92,10 @@ public class AnyElementProcessor implements StAXArtifactProcessor<Extension> {
             return;
         }
         String xml = (String) value;
-        XMLStreamReader reader = xmlInputFactory.createXMLStreamReader(new StringReader(xml));
+        XMLStreamReader reader = helper.createXMLStreamReader(new StringReader(xml));
         // Position the reader to the root element
         reader.nextTag();
-        XMLStreamSerializer serializer = new XMLStreamSerializer();
-        serializer.serialize(reader, writer);
+        helper.save(reader, writer);
     }
 
     public void resolve(Extension model, ModelResolver resolver) throws ContributionResolveException {
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/xml/XMLStreamSerializer.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/xml/XMLStreamSerializer.java
deleted file mode 100644
index 7c8ba4296e..0000000000
--- a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/xml/XMLStreamSerializer.java
+++ /dev/null
@@ -1,287 +0,0 @@
-/*
- * 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.tuscany.sca.contribution.processor.xml;
-
-import javax.xml.namespace.NamespaceContext;
-import javax.xml.stream.XMLStreamConstants;
-import javax.xml.stream.XMLStreamException;
-import javax.xml.stream.XMLStreamReader;
-import javax.xml.stream.XMLStreamWriter;
-
-/**
- * The XMLStreamSerializer pulls events from the XMLStreamReader and dumps into the XMLStreamWriter
- *
- * @version $Rev$ $Date$
- */
-public class XMLStreamSerializer implements XMLStreamConstants {
-    public static final String NAMESPACE_PREFIX = "ns";
-    private static int namespaceSuffix;
-
-    /*
-     * The behavior of the Serializer is such that it returns when it encounters the starting element for the second
-     * time. The depth variable tracks the depth of the Serializer and tells it when to return. Note that it is assumed
-     * that this Serialization starts on an Element.
-     */
-
-    /**
-     * Field depth
-     */
-    private int depth;
-
-    /**
-     * Generates a unique namespace prefix that is not in the scope of the NamespaceContext
-     * 
-     * @param nsCtxt
-     * @return string
-     */
-    private String generateUniquePrefix(NamespaceContext nsCtxt) {
-        String prefix = NAMESPACE_PREFIX + namespaceSuffix++;
-        // null should be returned if the prefix is not bound!
-        while (nsCtxt.getNamespaceURI(prefix) != null) {
-            prefix = NAMESPACE_PREFIX + namespaceSuffix++;
-        }
-
-        return prefix;
-    }
-
-    /**
-     * Method serialize.
-     * 
-     * @param node
-     * @param writer
-     * @throws XMLStreamException
-     */
-    public void serialize(XMLStreamReader node, XMLStreamWriter writer) throws XMLStreamException {
-        serializeNode(node, writer);
-    }
-
-    /**
-     * @param reader
-     * @param writer
-     * @throws XMLStreamException
-     */
-    protected void serializeAttributes(XMLStreamReader reader, XMLStreamWriter writer) throws XMLStreamException {
-        int count = reader.getAttributeCount();
-        String prefix;
-        String namespaceName;
-        String writerPrefix;
-        for (int i = 0; i < count; i++) {
-            prefix = reader.getAttributePrefix(i);
-            namespaceName = reader.getAttributeNamespace(i);
-            /*
-             * Due to parser implementations returning null as the namespace URI (for the empty namespace) we need to
-             * make sure that we deal with a namespace name that is not null. The best way to work around this issue is
-             * to set the namespace URI to "" if it is null
-             */
-            if (namespaceName == null) {
-                namespaceName = "";
-            }
-
-            writerPrefix = writer.getPrefix(namespaceName);
-
-            if (!"".equals(namespaceName)) {
-                // prefix has already being declared but this particular
-                // attrib has a
-                // no prefix attached. So use the prefix provided by the
-                // writer
-                if (writerPrefix != null && (prefix == null || prefix.equals(""))) {
-                    writer.writeAttribute(writerPrefix, namespaceName, reader.getAttributeLocalName(i), reader
-                        .getAttributeValue(i));
-
-                    // writer prefix is available but different from the
-                    // current
-                    // prefix of the attrib. We should be declaring the new
-                    // prefix
-                    // as a namespace declaration
-                } else if (prefix != null && !"".equals(prefix) && !prefix.equals(writerPrefix)) {
-                    writer.writeNamespace(prefix, namespaceName);
-                    writer.writeAttribute(prefix, namespaceName, reader.getAttributeLocalName(i), reader
-                        .getAttributeValue(i));
-
-                    // prefix is null (or empty), but the namespace name is
-                    // valid! it has not
-                    // being written previously also. So we need to generate
-                    // a prefix
-                    // here
-                } else if (prefix == null || prefix.equals("")) {
-                    prefix = generateUniquePrefix(writer.getNamespaceContext());
-                    writer.writeNamespace(prefix, namespaceName);
-                    writer.writeAttribute(prefix, namespaceName, reader.getAttributeLocalName(i), reader
-                        .getAttributeValue(i));
-                } else {
-                    writer.writeAttribute(prefix, namespaceName, reader.getAttributeLocalName(i), reader
-                        .getAttributeValue(i));
-                }
-            } else {
-                // empty namespace is equal to no namespace!
-                writer.writeAttribute(reader.getAttributeLocalName(i), reader.getAttributeValue(i));
-            }
-
-        }
-    }
-
-    /**
-     * Method serializeCData.
-     * 
-     * @param reader
-     * @param writer
-     * @throws XMLStreamException
-     */
-    protected void serializeCData(XMLStreamReader reader, XMLStreamWriter writer) throws XMLStreamException {
-        writer.writeCData(reader.getText());
-    }
-
-    /**
-     * Method serializeComment.
-     * 
-     * @param reader
-     * @param writer
-     * @throws XMLStreamException
-     */
-    protected void serializeComment(XMLStreamReader reader, XMLStreamWriter writer) throws XMLStreamException {
-        writer.writeComment(reader.getText());
-    }
-
-    /**
-     * @param reader
-     * @param writer
-     * @throws XMLStreamException
-     */
-    protected void serializeElement(XMLStreamReader reader, XMLStreamWriter writer) throws XMLStreamException {
-        String prefix = reader.getPrefix();
-        String nameSpaceName = reader.getNamespaceURI();
-        if (nameSpaceName != null) {
-            String writerPrefix = writer.getPrefix(nameSpaceName);
-            if (writerPrefix != null) {
-                writer.writeStartElement(nameSpaceName, reader.getLocalName());
-            } else {
-                if (prefix != null) {
-                    writer.writeStartElement(prefix, reader.getLocalName(), nameSpaceName);
-                    writer.writeNamespace(prefix, nameSpaceName);
-                    // writer.setPrefix(prefix, nameSpaceName);
-                } else {
-                    // [rfeng] We need to set default NS 1st before calling writeStateElement
-                    writer.setDefaultNamespace(nameSpaceName);
-                    writer.writeStartElement(nameSpaceName, reader.getLocalName());
-                    writer.writeDefaultNamespace(nameSpaceName);
-                }
-            }
-        } else {
-            writer.writeStartElement(reader.getLocalName());
-        }
-
-        // add the namespaces
-        int count = reader.getNamespaceCount();
-        String namespacePrefix;
-        for (int i = 0; i < count; i++) {
-            namespacePrefix = reader.getNamespacePrefix(i);
-            // [rfeng] The following is commented out to allow to default ns
-            // if (namespacePrefix != null && namespacePrefix.length() == 0) {
-            // continue;
-            // }
-
-            serializeNamespace(namespacePrefix, reader.getNamespaceURI(i), writer);
-        }
-
-        // add attributes
-        serializeAttributes(reader, writer);
-
-    }
-
-    /**
-     * Method serializeEndElement.
-     * 
-     * @param writer
-     * @throws XMLStreamException
-     */
-    protected void serializeEndElement(XMLStreamWriter writer) throws XMLStreamException {
-        writer.writeEndElement();
-    }
-
-    /**
-     * Method serializeNamespace.
-     * 
-     * @param prefix
-     * @param uri
-     * @param writer
-     * @throws XMLStreamException
-     */
-    private void serializeNamespace(String prefix, String uri, XMLStreamWriter writer) throws XMLStreamException {
-        String prefix1 = writer.getPrefix(uri);
-        if (prefix1 == null) {
-            writer.writeNamespace(prefix, uri);
-            // writer.setPrefix(prefix, uri);
-        }
-    }
-
-    /**
-     * Method serializeNode.
-     * 
-     * @param reader
-     * @param writer
-     * @throws XMLStreamException
-     */
-    protected void serializeNode(XMLStreamReader reader, XMLStreamWriter writer) throws XMLStreamException {
-        while (true) {
-            int event = reader.getEventType();
-            if (event == START_ELEMENT) {
-                serializeElement(reader, writer);
-                depth++;
-            } else if (event == ATTRIBUTE) {
-                serializeAttributes(reader, writer);
-            } else if (event == CHARACTERS) {
-                serializeText(reader, writer);
-            } else if (event == COMMENT) {
-                serializeComment(reader, writer);
-            } else if (event == CDATA) {
-                serializeCData(reader, writer);
-            } else if (event == END_ELEMENT) {
-                serializeEndElement(writer);
-                depth--;
-            } else if (event == START_DOCUMENT) {
-                depth++; // if a start document is found then increment
-                writer.writeStartDocument();
-                // the depth
-            } else if (event == END_DOCUMENT) {
-                if (depth != 0) {
-                    depth--; // for the end document - reduce the depth
-                }
-                writer.writeEndDocument();
-            }
-            if (depth == 0) {
-                break;
-            }
-            if (reader.hasNext()) {
-                reader.next();
-            } else {
-                break;
-            }
-        }
-    }
-
-    /**
-     * @param reader
-     * @param writer
-     * @throws XMLStreamException
-     */
-    protected void serializeText(XMLStreamReader reader, XMLStreamWriter writer) throws XMLStreamException {
-        writer.writeCharacters(reader.getText());
-    }
-}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/impl/JarContributionScanner.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/impl/JarContributionScanner.java
index f1fb6f2a70..2c5b849a20 100644
--- a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/impl/JarContributionScanner.java
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/impl/JarContributionScanner.java
@@ -22,7 +22,6 @@ package org.apache.tuscany.sca.contribution.scanner.impl;
 import java.io.IOException;
 import java.net.MalformedURLException;
 import java.net.URL;
-import java.net.URLConnection;
 import java.util.ArrayList;
 import java.util.HashSet;
 import java.util.List;
@@ -30,6 +29,7 @@ import java.util.Set;
 import java.util.jar.JarEntry;
 import java.util.jar.JarInputStream;
 
+import org.apache.tuscany.sca.common.java.io.IOHelper;
 import org.apache.tuscany.sca.contribution.Contribution;
 import org.apache.tuscany.sca.contribution.PackageType;
 import org.apache.tuscany.sca.contribution.processor.ContributionReadException;
@@ -68,9 +68,7 @@ public class JarContributionScanner implements ContributionScanner {
         // Assume the URL references a JAR file
         try {
             URL url = new URL(contribution.getLocation());
-            URLConnection connection = url.openConnection();
-            connection.setUseCaches(false);
-            JarInputStream jar = new JarInputStream(connection.getInputStream());
+            JarInputStream jar = new JarInputStream(IOHelper.openStream(url));
             try {
                 Set<String> names = new HashSet<String>();
                 while (true) {
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/xml/ContributionMetadataDocumentProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/xml/ContributionMetadataDocumentProcessor.java
index d5fa606997..0ab817e1bc 100644
--- a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/xml/ContributionMetadataDocumentProcessor.java
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/xml/ContributionMetadataDocumentProcessor.java
@@ -22,12 +22,12 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.net.URI;
 import java.net.URL;
-import java.net.URLConnection;
 
 import javax.xml.stream.XMLInputFactory;
 import javax.xml.stream.XMLStreamException;
 import javax.xml.stream.XMLStreamReader;
 
+import org.apache.tuscany.sca.common.java.io.IOHelper;
 import org.apache.tuscany.sca.contribution.ContributionMetadata;
 import org.apache.tuscany.sca.contribution.processor.ContributionReadException;
 import org.apache.tuscany.sca.contribution.processor.ContributionResolveException;
@@ -93,9 +93,7 @@ public class ContributionMetadataDocumentProcessor implements URLArtifactProcess
         try {
 
             // Create a stream reader
-            URLConnection connection = url.openConnection();
-            connection.setUseCaches(false);
-            urlStream = connection.getInputStream();
+            urlStream = IOHelper.openStream(url);
             XMLStreamReader reader = inputFactory.createXMLStreamReader(url.toString(), urlStream);
             reader.nextTag();