Add all parameters to get project of group api

src/main/java/org/gitlab4j/api/Constants.java

@@ -199,6 +199,28 @@ public String toString() {
         }
     }
 
+    /** Enum to use for ordering the results of getProjects() of GroupsApi. */
+    public enum GroupProjectOrderBy {
+
+        ID, NAME, PATH, CREATED_AT, UPDATED_AT, LAST_ACTIVITY_AT;
+        private static JacksonJsonEnumHelper<GroupProjectOrderBy> enumHelper = new JacksonJsonEnumHelper<>(GroupProjectOrderBy.class);
+
+        @JsonCreator
+        public static GroupProjectOrderBy forValue(String value) {
+            return enumHelper.forValue(value);
+        }
+
+        @JsonValue
+        public String toValue() {
+            return (enumHelper.toString(this));
+        }
+
+        @Override
+        public String toString() {
+            return (enumHelper.toString(this));
+        }
+    }
+
     /** Enum to use for specifying the scope when calling getPipelines(). */
     public enum PipelineScope {
 

src/main/java/org/gitlab4j/api/GroupApi.java

@@ -224,6 +224,46 @@ public Pager<Group> getSubGroups(Integer groupId, List<Integer> skipGroups, Bool
         return (new Pager<Group>(this, Group.class, itemsPerPage, formData.asMap(), "groups", groupId, "subgroups"));
     }
 
+    /**
+     * Get a list of projects belonging to the specified group ID.
+     *
+     * GET /groups/:id/projects
+     *
+     * @param groupId the group ID to list the projects for
+     * @param archived Limit by archived status
+     * @param visibility Limit by visibility public, internal, or private 
+     * @param orderBy Return projects ordered by id, name, path, created_at, updated_at, or last_activity_at fields. Default is created_at
+     * @param sortOrder Return projects sorted in asc or desc order. Default is desc
+     * @param search Return list of authorized projects matching the search criteria
+     * @param simple Return only the ID, URL, name, and path of each project
+     * @param owned Limit by projects owned by the current user
+     * @param starred Limit by projects starred by the current user
+     * @param withIssuesEnabled Limit by enabled issues feature
+     * @param withMergeRequestsEnabled Limit by enabled merge requests feature
+     * @param withCustomAttributes Include custom attributes in response (admins only)
+     * @return a list of projects belonging to the specified group ID
+     * @throws GitLabApiException if any exception occurs
+     */
+  public List<Project> getProjects(int groupId, Boolean archived, Visibility visibility, GroupProjectOrderBy orderBy,
+      SortOrder sortOrder, String search, Boolean simple, Boolean owned, Boolean starred, Boolean withIssuesEnabled,
+      Boolean withMergeRequestsEnabled, Boolean withCustomAttributes) throws GitLabApiException {
+      Form formData = new GitLabApiForm()
+          .withParam("archived", archived)
+          .withParam("visibility", visibility)
+          .withParam("order_by", orderBy)
+          .withParam("order_by", orderBy)
+          .withParam("sort", sortOrder)
+          .withParam("search", search)
+          .withParam("simple", simple)
+          .withParam("owned", owned)
+          .withParam("starred", starred)
+          .withParam("with_issues_enabled", withIssuesEnabled)
+          .withParam("with_merge_requests_enabled", withMergeRequestsEnabled)
+          .withParam("with_custom_attributes", withCustomAttributes);
+        Response response = get(Response.Status.OK, formData.asMap(), "groups", groupId, "projects");
+        return (response.readEntity(new GenericType<List<Project>>() {}));
+    }
+
     /**
      * Get a list of projects belonging to the specified group ID.
      *