Adds simple interfaces for ETClient and ETRestConnection.

Only method exposed on ETClient at the moment is getRestConnection,
making it clear that this is the only use of the client for non-SOAP
endpoints.

pom.xml

@@ -249,6 +249,14 @@
           </dependency>
         </dependencies>
       </plugin>
+        <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <configuration>
+                <source>1.6</source>
+                <target>1.6</target>
+            </configuration>
+        </plugin>
     </plugins>
     <pluginManagement>
       <plugins>

src/main/java/com/exacttarget/fuelsdk/ETClient.java

@@ -55,7 +55,7 @@
  * client library.
  */
 
-public class ETClient {
+public class ETClient implements IETClient {
     private static Logger logger = Logger.getLogger(ETClient.class);
 
     private static final String DEFAULT_PROPERTIES_FILE_NAME =
@@ -76,13 +76,6 @@ public class ETClient {
     private String clientId = null;
     private String clientSecret = null;
 
-    private String username = null;
-    private String password = null;
-
-    private String endpoint = null;
-    private String authEndpoint = null;
-    private String soapEndpoint = null;
-
     private Boolean autoHydrateObjects = true;
 
     private Gson gson = null;
@@ -129,18 +122,18 @@ public ETClient(ETConfiguration configuration)
         clientId = configuration.get("clientId");
         clientSecret = configuration.get("clientSecret");
 
-        username = configuration.get("username");
-        password = configuration.get("password");
+        String username = configuration.get("username");
+        String password = configuration.get("password");
 
-        endpoint = configuration.get("endpoint");
+        String endpoint = configuration.get("endpoint");
         if (endpoint == null) {
             endpoint = DEFAULT_ENDPOINT;
         }
-        authEndpoint = configuration.get("authEndpoint");
+        String authEndpoint = configuration.get("authEndpoint");
         if (authEndpoint == null) {
             authEndpoint = DEFAULT_AUTH_ENDPOINT;
         }
-        soapEndpoint = configuration.get("soapEndpoint");
+        String soapEndpoint = configuration.get("soapEndpoint");
 
         GsonBuilder gsonBuilder = new GsonBuilder()
             .excludeFieldsWithoutExposeAnnotation()
@@ -250,6 +243,7 @@ public Gson getGson() {
      * 
      * @return      The ETRestConnection
      */
+    @Override
     public ETRestConnection getRestConnection() {
         return restConnection;
     }

src/main/java/com/exacttarget/fuelsdk/ETRestConnection.java

@@ -58,7 +58,7 @@
  * connection to the Salesforce Marketing Cloud REST API.
  */
 
-public class ETRestConnection {
+public class ETRestConnection implements IETRestConnection {
     private static Logger logger = Logger.getLogger(ETRestConnection.class);
 
     private ETClient client = null;
@@ -100,6 +100,7 @@ public ETRestConnection(ETClient client, String endpoint, boolean isAuthConnecti
      * @param   path    The path to GET the response
      * @return  The Response object
      */
+    @Override
     public Response get(String path)
         throws ETSdkException
     {
@@ -126,6 +127,7 @@ public Response get(String path)
      * @param   path    The path to POST or create
      * @return  The Response object
      */
+    @Override
     public Response post(String path, String payload)
         throws ETSdkException
     {
@@ -152,6 +154,7 @@ public Response post(String path, String payload)
      * @param   path    The path to PATCH or update
      * @return  The Response object
      */
+    @Override
     public Response patch(String path, String payload)
         throws ETSdkException
     {
@@ -178,6 +181,7 @@ public Response patch(String path, String payload)
      * @param   path    The path to DELETE
      * @return  The Response object
      */
+    @Override
     public Response delete(String path)
         throws ETSdkException
     {

src/main/java/com/exacttarget/fuelsdk/IETClient.java

@@ -0,0 +1,5 @@
+package com.exacttarget.fuelsdk;
+
+public interface IETClient {
+    IETRestConnection getRestConnection();
+}

src/main/java/com/exacttarget/fuelsdk/IETRestConnection.java

@@ -0,0 +1,10 @@
+package com.exacttarget.fuelsdk;
+
+import com.exacttarget.fuelsdk.ETRestConnection.Response;
+
+public interface IETRestConnection {
+    Response get(String path) throws ETSdkException;
+    Response post(String path, String payload) throws ETSdkException;
+    Response patch(String path, String payload) throws ETSdkException;
+    Response delete(String path) throws ETSdkException;
+}