code: public DeleteMessageBatchResult withSuccessful(DeleteMessageBatchResultEntry... successful) {
          if (this.successful == null) {
              setSuccessful(new com.amazonaws.internal.SdkInternalList<DeleteMessageBatchResultEntry>(successful.length));
          }
          for (DeleteMessageBatchResultEntry ele : successful) {
              this.successful.add(ele);
          }
          return this;
      }
docs: <p>
  A list of <code> <a>DeleteMessageBatchResultEntry</a> </code> items.
  </p>
  <p>
  <b>NOTE:</b> This method appends the values to the existing list (if any). Use
  {@link #setSuccessful(java.util.Collection)} or {@link #withSuccessful(java.util.Collection)} if you want to
  override the existing values.
  </p>
  
  @param successful
  A list of <code> <a>DeleteMessageBatchResultEntry</a> </code> items.
  @return Returns a reference to this object so that method calls can be chained together.