Some more javadoc comments

Author: jmartisk

client/api/src/main/java/io/smallrye/graphql/client/core/FragmentOrOperation.java

@@ -1,4 +1,9 @@
 package io.smallrye.graphql.client.core;
 
+/**
+ * Represents a node in a GraphQL document that can contain either an operation (query/mutation/subscription),
+ * or a definition of a named fragment. On the top level, a GraphQL document basically consists of a list
+ * of these nodes.
+ */
 public interface FragmentOrOperation extends Buildable {
 }

client/api/src/main/java/io/smallrye/graphql/client/core/FragmentReference.java

@@ -2,14 +2,26 @@
 
 import static io.smallrye.graphql.client.core.utils.ServiceUtils.getNewInstanceOf;
 
+/**
+ * Represents a reference to a named fragment.
+ */
 public interface FragmentReference extends FieldOrFragment {
 
+    /**
+     * Create a fragment reference by specifying the name of the target fragment.
+     * In the resulting document, this will appear as `...FRAGMENTNAME`
+     */
     static FragmentReference fragmentRef(String name) {
         FragmentReference ref = getNewInstanceOf(FragmentReference.class);
         ref.setName(name);
         return ref;
     }
 
+    /**
+     * Create a fragment reference by providing a built instance of a named fragment.
+     * This will actually only use the name of the fragment - in the resulting document,
+     * this will appear as `...FRAGMENTNAME`
+     */
     static FragmentReference fragmentRef(Fragment fragment) {
         FragmentReference ref = getNewInstanceOf(FragmentReference.class);
         ref.setName(fragment.getName());