SWS-894 - Introduce interface to offer WebServiceConnection headers

* Created an interface to mark where request and response headers may be accessed
* Updated related classes to use the interface, and in turn, update method visibility
* There are sets of classes aimed at requests and another at repsonses. Have interfaces to serve both, for symmetry.

spring-ws-core/src/main/java/org/springframework/ws/transport/AbstractReceiverConnection.java

@@ -25,9 +25,11 @@ import java.util.Iterator;
  * Abstract base class for {@link WebServiceConnection} implementations used for receiving requests.
  *
  * @author Arjen Poutsma
+ * @author Greg Turnquist
  * @since 1.0.0
  */
-public abstract class AbstractReceiverConnection extends AbstractWebServiceConnection {
+public abstract class AbstractReceiverConnection extends AbstractWebServiceConnection implements
+		HeadersAwareReceiverWebServiceConnection {
 
 	private TransportInputStream requestInputStream;
 
@@ -58,30 +60,9 @@ public abstract class AbstractReceiverConnection extends AbstractWebServiceConne
 	protected void onClose() throws IOException {
 	}
 
-	/**
-	 * Returns an iteration over all the header names this request contains. Returns an empty {@code Iterator} if
-	 * there are no headers.
-	 */
-	protected abstract Iterator<String> getRequestHeaderNames() throws IOException;
-
-	/**
-	 * Returns an iteration over all the string values of the specified header. Returns an empty {@code Iterator}
-	 * if there are no headers of the specified name.
-	 */
-	protected abstract Iterator<String> getRequestHeaders(String name) throws IOException;
-
 	/** Returns the input stream to read the response from. */
 	protected abstract InputStream getRequestInputStream() throws IOException;
 
-	/**
-	 * Adds a response header with the given name and value. This method can be called multiple times, to allow for
-	 * headers with multiple values.
-	 *
-	 * @param name	the name of the header
-	 * @param value the value of the header
-	 */
-	protected abstract void addResponseHeader(String name, String value) throws IOException;
-
 	/** Returns the output stream to write the request to. */
 	protected abstract OutputStream getResponseOutputStream() throws IOException;
 

spring-ws-core/src/main/java/org/springframework/ws/transport/AbstractSenderConnection.java

@@ -25,9 +25,11 @@ import java.util.Iterator;
  * Abstract base class for {@link WebServiceConnection} implementations used for sending requests.
  *
  * @author Arjen Poutsma
+ * @author Greg Turnquist
  * @since 1.0.0
  */
-public abstract class AbstractSenderConnection extends AbstractWebServiceConnection {
+public abstract class AbstractSenderConnection extends AbstractWebServiceConnection implements
+		HeadersAwareSenderWebServiceConnection {
 
 	private TransportOutputStream requestOutputStream;
 
@@ -66,30 +68,9 @@ public abstract class AbstractSenderConnection extends AbstractWebServiceConnect
 	/** Indicates whether this connection has a response. */
 	protected abstract boolean hasResponse() throws IOException;
 
-	/**
-	 * Adds a request header with the given name and value. This method can be called multiple times, to allow for
-	 * headers with multiple values.
-	 *
-	 * @param name	the name of the header
-	 * @param value the value of the header
-	 */
-	protected abstract void addRequestHeader(String name, String value) throws IOException;
-
 	/** Returns the output stream to write the request to. */
 	protected abstract OutputStream getRequestOutputStream() throws IOException;
 
-	/**
-	 * Returns an iteration over all the header names this request contains. Returns an empty {@code Iterator} if
-	 * there are no headers.
-	 */
-	protected abstract Iterator<String> getResponseHeaderNames() throws IOException;
-
-	/**
-	 * Returns an iteration over all the string values of the specified header. Returns an empty {@code Iterator}
-	 * if there are no headers of the specified name.
-	 */
-	protected abstract Iterator<String> getResponseHeaders(String name) throws IOException;
-
 	/** Returns the input stream to read the response from. */
 	protected abstract InputStream getResponseInputStream() throws IOException;
 

spring-ws-core/src/main/java/org/springframework/ws/transport/HeadersAwareReceiverWebServiceConnection.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2005-2015 the original author or authors.
+ *
+ * Licensed 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.springframework.ws.transport;
+
+import java.io.IOException;
+import java.util.Iterator;
+
+/**
+ * Interface to define access to header information for certain {@link WebServiceConnection} implementations.
+ *
+ * @author Greg Turnquist
+ * @since 2.3
+ */
+public interface HeadersAwareReceiverWebServiceConnection {
+
+	/**
+	 * Returns an iteration over all the header names this request contains. Returns an empty {@code Iterator} if
+	 * there are no headers.
+	 */
+	Iterator<String> getRequestHeaderNames() throws IOException;
+
+	/**
+	 * Returns an iteration over all the string values of the specified header. Returns an empty {@code Iterator}
+	 * if there are no headers of the specified name.
+	 */
+	Iterator<String> getRequestHeaders(String name) throws IOException;
+
+	/**
+	 * Adds a response header with the given name and value. This method can be called multiple times, to allow for
+	 * headers with multiple values.
+	 *
+	 * @param name	the name of the header
+	 * @param value the value of the header
+	 */
+	void addResponseHeader(String name, String value) throws IOException;
+
+}

spring-ws-core/src/main/java/org/springframework/ws/transport/HeadersAwareSenderWebServiceConnection.java

@@ -0,0 +1,48 @@
+/*
+ * Copyright 2005-2015 the original author or authors.
+ *
+ * Licensed 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.springframework.ws.transport;
+
+import java.io.IOException;
+import java.util.Iterator;
+
+/**
+ * @author Greg Turnquist
+ * @since 2.3
+ */
+public interface HeadersAwareSenderWebServiceConnection {
+
+	/**
+	 * Returns an iteration over all the header names this request contains. Returns an empty {@code Iterator} if
+	 * there are no headers.
+	 */
+	Iterator<String> getResponseHeaderNames() throws IOException;
+
+	/**
+	 * Returns an iteration over all the string values of the specified header. Returns an empty {@code Iterator}
+	 * if there are no headers of the specified name.
+	 */
+	Iterator<String> getResponseHeaders(String name) throws IOException;
+
+	/**
+	 * Adds a request header with the given name and value. This method can be called multiple times, to allow for
+	 * headers with multiple values.
+	 *
+	 * @param name	the name of the header
+	 * @param value the value of the header
+	 */
+	void addRequestHeader(String name, String value) throws IOException;
+
+}

spring-ws-core/src/main/java/org/springframework/ws/transport/http/ClientHttpRequestConnection.java

@@ -36,6 +36,7 @@ import org.springframework.ws.WebServiceMessage;
  *
  * @author Krzysztof Trojan
  * @author Arjen Poutsma
+ * @author Greg Turnquist
  * @since 2.2
  */
 public class ClientHttpRequestConnection extends AbstractHttpSenderConnection {
@@ -67,7 +68,7 @@ public class ClientHttpRequestConnection extends AbstractHttpSenderConnection {
 	// Sending request
 
 	@Override
-	protected void addRequestHeader(String name, String value) throws IOException {
+	public void addRequestHeader(String name, String value) throws IOException {
 		request.getHeaders().add(name, value);
 	}
 
@@ -89,12 +90,12 @@ public class ClientHttpRequestConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected Iterator<String> getResponseHeaderNames() throws IOException {
+	public Iterator<String> getResponseHeaderNames() throws IOException {
 		return response.getHeaders().keySet().iterator();
 	}
 
 	@Override
-	protected Iterator<String> getResponseHeaders(String name) throws IOException {
+	public Iterator<String> getResponseHeaders(String name) throws IOException {
 		List<String> headers = response.getHeaders().get(name);
 		return headers != null ? headers.iterator() :
 				Collections.<String>emptyList().iterator();

spring-ws-core/src/main/java/org/springframework/ws/transport/http/CommonsHttpConnection.java

@@ -41,6 +41,7 @@ import org.springframework.ws.transport.WebServiceConnection;
  * PostMethod}.
  *
  * @author Arjen Poutsma
+ * @author Greg Turnquist
  * @since 1.0.0
  * @deprecated In favor of {@link HttpComponentsConnection}
  */
@@ -98,7 +99,7 @@ public class CommonsHttpConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected void addRequestHeader(String name, String value) throws IOException {
+	public void addRequestHeader(String name, String value) throws IOException {
 		postMethod.addRequestHeader(name, value);
 	}
 
@@ -151,7 +152,7 @@ public class CommonsHttpConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected Iterator<String> getResponseHeaderNames() throws IOException {
+	public Iterator<String> getResponseHeaderNames() throws IOException {
 		Header[] headers = postMethod.getResponseHeaders();
 		String[] names = new String[headers.length];
 		for (int i = 0; i < headers.length; i++) {
@@ -161,7 +162,7 @@ public class CommonsHttpConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected Iterator<String> getResponseHeaders(String name) throws IOException {
+	public Iterator<String> getResponseHeaders(String name) throws IOException {
 		Header[] headers = postMethod.getResponseHeaders(name);
 		String[] values = new String[headers.length];
 		for (int i = 0; i < headers.length; i++) {

spring-ws-core/src/main/java/org/springframework/ws/transport/http/HttpComponentsConnection.java

@@ -45,6 +45,7 @@ import org.springframework.ws.transport.WebServiceConnection;
  * @author Alan Stewart
  * @author Barry Pitman
  * @author Arjen Poutsma
+ * @author Greg Turnquist
  * @since 2.1.0
  */
 public class HttpComponentsConnection extends AbstractHttpSenderConnection {
@@ -100,7 +101,7 @@ public class HttpComponentsConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected void addRequestHeader(String name, String value) throws IOException {
+	public void addRequestHeader(String name, String value) throws IOException {
 		httpPost.addHeader(name, value);
 	}
 
@@ -154,7 +155,7 @@ public class HttpComponentsConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected Iterator<String> getResponseHeaderNames() throws IOException {
+	public Iterator<String> getResponseHeaderNames() throws IOException {
 		Header[] headers = httpResponse.getAllHeaders();
 		String[] names = new String[headers.length];
 		for (int i = 0; i < headers.length; i++) {
@@ -164,7 +165,7 @@ public class HttpComponentsConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected Iterator<String> getResponseHeaders(String name) throws IOException {
+	public Iterator<String> getResponseHeaders(String name) throws IOException {
 		Header[] headers = httpResponse.getHeaders(name);
 		String[] values = new String[headers.length];
 		for (int i = 0; i < headers.length; i++) {

spring-ws-core/src/main/java/org/springframework/ws/transport/http/HttpServletConnection.java

@@ -38,6 +38,7 @@ import org.springframework.ws.transport.support.EnumerationIterator;
  * Implementation of {@link WebServiceConnection} that is based on the Servlet API.
  *
  * @author Arjen Poutsma
+ * @author Greg Turnquist
  * @since 1.0.0
  */
 public class HttpServletConnection extends AbstractReceiverConnection
@@ -105,13 +106,13 @@ public class HttpServletConnection extends AbstractReceiverConnection
 
 	@Override
 	@SuppressWarnings("unchecked")
-	protected Iterator<String> getRequestHeaderNames() throws IOException {
+	public Iterator<String> getRequestHeaderNames() throws IOException {
 		return new EnumerationIterator<String>(getHttpServletRequest().getHeaderNames());
 	}
 
 	@Override
 	@SuppressWarnings("unchecked")
-	protected Iterator<String> getRequestHeaders(String name) throws IOException {
+	public Iterator<String> getRequestHeaders(String name) throws IOException {
 		return new EnumerationIterator<String>(getHttpServletRequest().getHeaders(name));
 	}
 
@@ -125,7 +126,7 @@ public class HttpServletConnection extends AbstractReceiverConnection
 	*/
 
 	@Override
-	protected void addResponseHeader(String name, String value) throws IOException {
+	public void addResponseHeader(String name, String value) throws IOException {
 		getHttpServletResponse().addHeader(name, value);
 	}
 

spring-ws-core/src/main/java/org/springframework/ws/transport/http/HttpUrlConnection.java

@@ -37,6 +37,7 @@ import org.springframework.ws.transport.WebServiceConnection;
  * Implementation of the {@link WebServiceConnection} interface that uses a {@link HttpURLConnection}.
  *
  * @author Arjen Poutsma
+ * @author Greg Turnquist
  * @since 1.0.0
  */
 public class HttpUrlConnection extends AbstractHttpSenderConnection {
@@ -76,7 +77,7 @@ public class HttpUrlConnection extends AbstractHttpSenderConnection {
 	 */
 
 	@Override
-	protected void addRequestHeader(String name, String value) throws IOException {
+	public void addRequestHeader(String name, String value) throws IOException {
 		connection.addRequestProperty(name, value);
 	}
 
@@ -100,7 +101,7 @@ public class HttpUrlConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected Iterator<String> getResponseHeaderNames() throws IOException {
+	public Iterator<String> getResponseHeaderNames() throws IOException {
 		List<String> headerNames = new ArrayList<String>();
 		// Header field 0 is the status line, so we start at 1
 		int i = 1;
@@ -116,7 +117,7 @@ public class HttpUrlConnection extends AbstractHttpSenderConnection {
 	}
 
 	@Override
-	protected Iterator<String> getResponseHeaders(String name) throws IOException {
+	public Iterator<String> getResponseHeaders(String name) throws IOException {
 		String headerField = connection.getHeaderField(name);
 		if (headerField == null) {
 			return Collections.<String>emptyList().iterator();