add option rename-operation-group

fluentnamer/src/main/java/com/azure/autorest/fluent/transformer/FluentTransformer.java

@@ -42,6 +42,7 @@ public CodeModel preTransform(CodeModel codeModel) {
 
     public CodeModel postTransform(CodeModel codeModel) {
         codeModel = new OperationGroupFilter(fluentJavaSettings.getJavaNamesForRemoveOperationGroup()).process(codeModel);
+        codeModel = new OperationGroupRenamer(fluentJavaSettings.getJavaNamesForRenameOperationGroup()).process(codeModel);
         codeModel = new NamingConflictResolver().process(codeModel);
         codeModel = new SchemaRenamer(fluentJavaSettings.getJavaNamesForRenameModel()).process(codeModel);
         codeModel = new OperationNameNormalization().process(codeModel);

fluentnamer/src/main/java/com/azure/autorest/fluent/transformer/OperationGroupRenamer.java

@@ -0,0 +1,37 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package com.azure.autorest.fluent.transformer;
+
+import com.azure.autorest.extension.base.model.codemodel.CodeModel;
+import com.azure.autorest.extension.base.plugin.PluginLogger;
+import com.azure.autorest.fluent.util.Utils;
+import com.azure.autorest.fluentnamer.FluentNamer;
+import com.azure.autorest.preprocessor.namer.CodeNamer;
+import org.slf4j.Logger;
+
+import java.util.Map;
+
+public class OperationGroupRenamer {
+
+    private final Logger logger = new PluginLogger(FluentNamer.getPluginInstance(), OperationGroupRenamer.class);
+
+    private final Map<String, String> renameOperationGroup;
+
+    public OperationGroupRenamer(Map<String, String> renameOperationGroup) {
+        this.renameOperationGroup = renameOperationGroup;
+    }
+
+    public CodeModel process(CodeModel codeModel) {
+        // rename operation group
+        codeModel.getOperationGroups().forEach(og -> {
+            String methodGroupName = CodeNamer.getPlural(Utils.getJavaName(og));
+            String rename = renameOperationGroup.get(methodGroupName);
+            if (rename != null) {
+                og.getLanguage().getJava().setName(rename);
+                logger.info("Renamed operation group from '{}' to '{}'.", methodGroupName, rename);
+            }
+        });
+        return codeModel;
+    }
+}

fluentnamer/src/main/java/com/azure/autorest/fluent/util/FluentJavaSettings.java

@@ -66,6 +66,8 @@ public class FluentJavaSettings {
 
     private final Set<String> javaNamesForPropertyIncludeAlways = new HashSet<>();
 
+    private final Map<String, String> renameOperationGroup = new HashMap<>();
+
     private String pomFilename = "pom.xml";
 
     private String artifactVersion;
@@ -134,6 +136,10 @@ public Set<String> getJavaNamesForPropertyIncludeAlways() {
         return javaNamesForPropertyIncludeAlways;
     }
 
+    public Map<String, String> getJavaNamesForRenameOperationGroup() {
+        return renameOperationGroup;
+    }
+
     public String getPomFilename() {
         return pomFilename;
     }
@@ -181,6 +187,21 @@ private void loadSettings() {
 
         loadStringSetting("remove-operation-group", s -> splitStringToSet(s, javaNamesForRemoveOperationGroup));
 
+        loadStringSetting("rename-operation-group", s -> {
+            if (!CoreUtils.isNullOrEmpty(s)) {
+                String[] renamePairs = s.split(Pattern.quote(","));
+                for (String pair : renamePairs) {
+                    String[] fromAndTo = pair.split(Pattern.quote(":"));
+                    if (fromAndTo.length == 2) {
+                        String from = fromAndTo[0];
+                        String to = fromAndTo[1];
+                        if (!CoreUtils.isNullOrEmpty(from) && !CoreUtils.isNullOrEmpty(to)) {
+                            renameOperationGroup.put(from, to);
+                        }
+                    }
+                }
+            }
+        });
 //        loadBooleanSetting("track1-naming", b -> track1Naming = b);
 //        loadBooleanSetting("resource-property-as-subresource", b -> resourcePropertyAsSubResource = b);