code: public ModifySnapshotAttributeRequest withGroupNames(String... groupNames) {
          if (this.groupNames == null) {
              setGroupNames(new com.amazonaws.internal.SdkInternalList<String>(groupNames.length));
          }
          for (String ele : groupNames) {
              this.groupNames.add(ele);
          }
          return this;
      }
docs: <p>
  The group to modify for the snapshot.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setGroupNames(java.util.Collection)} or {@link #withGroupNames(java.util.Collection)} if you want to
  override the existing values.
  </p>
  
  @param groupNames
  The group to modify for the snapshot.
  @return Returns a reference to this object so that method calls can be chained together.