public String getCopyAll() {
      return copyAll;
    }
The method to copy another collection into this builder. It is {@code addAll} for
one-dimensional collections like {@code ImmutableList} and {@code ImmutableSet}, and it is
{@code putAll} for two-dimensional collections like {@code ImmutableMap} and {@code
ImmutableTable}.
value/src/main/java/com/google/auto/value/processor/PropertyBuilderClassifier.java