public Field field(int tag) {
    for (Field field : declaredFields) {
      if (field.tag() == tag) {
        return field;
      }
    }
    for (Field field : extensionFields) {
      if (field.tag() == tag) {
        return field;
      }
    }
    return null;
  }
public Field field ( int tag ) { for ( Field field : declaredFields ) { if ( field . tag ( ) == tag ) { return field ; } } for ( Field field : extensionFields ) { if ( field . tag ( ) == tag ) { return field ; } } return null ; }
Returns the field tagged {@code tag}, or null if this type has no such field.