(Codegen) Add defaults to the endpointProvider interface method, for customers that have implemented the client interfaces themselves. (#3598)

Author: millems

codegen/src/main/java/software/amazon/awssdk/codegen/poet/builder/BaseClientBuilderInterface.java

@@ -137,12 +137,14 @@ private MethodSpec serviceConfigurationConsumerBuilderMethod() {
 
     private MethodSpec endpointProviderMethod() {
         return MethodSpec.methodBuilder("endpointProvider")
-                         .addModifiers(Modifier.PUBLIC, Modifier.ABSTRACT)
+                         .addModifiers(Modifier.PUBLIC, Modifier.DEFAULT)
                          .addParameter(endpointRulesSpecUtils.providerInterfaceName(), "endpointProvider")
-            .addJavadoc("Set the {@link $T} implementation that will be used by the client to determine the endpoint for each "
-                        + "request. This is optional; if none is provided a default implementation will be used the SDK.",
-                        endpointRulesSpecUtils.providerInterfaceName())
+                         .addJavadoc("Set the {@link $T} implementation that will be used by the client to determine "
+                                     + "the endpoint for each request. This is optional; if none is provided a "
+                                     + "default implementation will be used the SDK.",
+                                     endpointRulesSpecUtils.providerInterfaceName())
                          .returns(TypeVariableName.get("B"))
+                         .addStatement("throw new $T()", UnsupportedOperationException.class)
                          .build();
     }
 

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/builder/test-bearer-auth-client-builder-interface.java

@@ -15,7 +15,9 @@ public interface JsonBaseClientBuilder<B extends JsonBaseClientBuilder<B, C>, C>
      * Set the {@link JsonEndpointProvider} implementation that will be used by the client to determine the endpoint for
      * each request. This is optional; if none is provided a default implementation will be used the SDK.
      */
-    B endpointProvider(JsonEndpointProvider endpointProvider);
+    default B endpointProvider(JsonEndpointProvider endpointProvider) {
+        throw new UnsupportedOperationException();
+    }
 
     /**
      * Set the token provider to use for bearer token authorization. This is optional, if none is provided, the SDK will

codegen/src/test/resources/software/amazon/awssdk/codegen/poet/builder/test-client-builder-interface.java

@@ -22,7 +22,9 @@ default B serviceConfiguration(Consumer<ServiceConfiguration.Builder> serviceCon
      * Set the {@link JsonEndpointProvider} implementation that will be used by the client to determine the endpoint for
      * each request. This is optional; if none is provided a default implementation will be used the SDK.
      */
-    B endpointProvider(JsonEndpointProvider endpointProvider);
+    default B endpointProvider(JsonEndpointProvider endpointProvider) {
+        throw new UnsupportedOperationException();
+    }
 
     /**
      * Set the token provider to use for bearer token authorization. This is optional, if none is provided, the SDK will