in hadoop-api-shim/src/main/java/org/apache/hadoop/fs/shim/impl/Preconditions.java [105:122]
public static <T> T checkNotNull(final T obj, final String message,
final Object... values) {
// Deferring the evaluation of the message is a tradeoff between the cost
// of constructing lambda Vs constructing a string object.
// Using lambda would allocate an object on every call:
// return checkNotNull(obj, () -> String.format(message, values));
if (obj == null) {
String msg;
try {
msg = String.format(message, values);
} catch (Exception e) {
LOG.debug("Error formatting message", e);
msg = VALIDATE_IS_NOT_NULL_EX_MESSAGE;
}
throw new NullPointerException(msg);
}
return obj;
}