Properly close/flush TransportOutputStream.

Resolves #1207.

Author: leaqui

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

@@ -47,7 +47,9 @@ private InputStream getInputStream() throws IOException {
 
 	@Override
 	public void close() throws IOException {
-		getInputStream().close();
+		if (inputStream != null) {
+			getInputStream().close();
+		}
 	}
 
 	@Override

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

@@ -45,12 +45,16 @@ private OutputStream getOutputStream() throws IOException {
 
 	@Override
 	public void close() throws IOException {
-		getOutputStream().close();
+		if (outputStream != null) {
+			getOutputStream().close();
+		}
 	}
 
 	@Override
 	public void flush() throws IOException {
-		getOutputStream().flush();
+		if (outputStream != null) {
+			getOutputStream().flush();
+		}
 	}
 
 	@Override