Issue #11 - added alternate method for adding floating IP without the fixed address param

Author: gondor

src/main/java/org/openstack4j/api/compute/ComputeFloatingIPService.java

@@ -56,6 +56,15 @@ public interface ComputeFloatingIPService extends RestService {
 	 */
 	ActionResponse addFloatingIP(Server server, String fixedIpAddress, String ipAddress);
 
+	/**
+	 * Adds floating-ip to server.
+	 *
+	 * @param server the server
+	 * @param ipAddress the ip address
+	 * @return the action response
+	 */
+	ActionResponse addFloatingIP(Server server, String ipAddress);
+	
 	/**
 	 * Remove floating-ip from server
 	 *

src/main/java/org/openstack4j/openstack/compute/internal/ComputeFloatingIPServiceImpl.java

@@ -59,6 +59,9 @@ public void deallocateIP(String id) {
    */
   @Override
   public ActionResponse addFloatingIP(Server server, String fixedIpAddress, String ipAddress) {
+  	if (fixedIpAddress == null)
+  		return addFloatingIP(server, ipAddress);
+  	
     checkNotNull(server);
     checkNotNull(fixedIpAddress);
     checkNotNull(ipAddress);
@@ -69,6 +72,21 @@ public ActionResponse addFloatingIP(Server server, String fixedIpAddress, String
     String uri = uri("/servers/%s/action", server.getId());
     return invokeAction(uri, action, innerJson);
   }
+  
+  /**
+   * {@inheritDoc}
+   */
+  @Override
+	public ActionResponse addFloatingIP(Server server, String ipAddress) {
+  	checkNotNull(server);
+    checkNotNull(ipAddress);
+    
+    String action = "addFloatingIp";
+    String innerJson = String.format("{ \"address\": \"%s\" }", ipAddress);
+    
+    String uri = uri("/servers/%s/action", server.getId());
+    return invokeAction(uri, action, innerJson);
+	}
 
   /**
    * {@inheritDoc}