Javadoc
Obtains the value of the given field, or the default value if it is
not set. For primitive fields, the boxed primitive value is returned.
For enum fields, the EnumValueDescriptor for the value is returned. For
embedded message fields, the sub-message is returned. For repeated
fields, a java.util.List is returned. For present string fields, a
ByteString is returned representing the bytes that the field contains.