Method putOnce

core/src/processing/data/JSONObject.java:1353–1361

Put a key/value pair in the JSONObject, but only if the key and the value are both non-null, and only if there is not already a member with that name. @param key @param value @return this. @throws RuntimeException if the key is a duplicate, or if #put(String,Object) throws.

(String key, Object value)

   * {@link #put(String,Object)} throws.
   */
  private JSONObject putOnce(String key, Object value) {
    if (key != null && value != null) {
      if (this.opt(key) != null) {
        throw new RuntimeException("Duplicate key \"" + key + "\"");
      }
      this.put(key, value);
    }
    return this;
  }


//  /**