Method put

api/src/main/java/io/grpc/Metadata.java:342–353

Adds the key, value pair. If key already has values, value is added to the end. Duplicate values for the same key are permitted. @throws NullPointerException if key or value is null

(Key<T> key, T value)

   * @throws NullPointerException if key or value is null
   */
  public <T> void put(Key<T> key, T value) {
    Preconditions.checkNotNull(key, "key");
    Preconditions.checkNotNull(value, "value");
    maybeExpand();
    name(size, key.asciiName());
    if (key.serializesToStreams()) {
      value(size, LazyValue.create(key, value));
    } else {
      value(size, key.toBytes(value));
    }
    size++;
  }

  private void maybeExpand() {
    if (len() == 0 || len() == cap()) {