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