How to use org.apache.james.mailbox.model

  private boolean hasPositiveUserKey(MailboxACL.Entry entry) {
    return !entry.getKey().isNegative()
      && entry.getKey().getNameType().equals(MailboxACL.NameType.user);
  }
}

public Blob toBlob() {
  return Blob.builder()
    .id(BlobId.fromBytes(bytes))
    .payload(bytes)
    .contentType(type)
    .build();
}

/**
 * Creates a filter matching messages whose Address header contains the
 * given address. The address header of the message MUST get canonicalized
 * before try to match it.
 * 
 * @param type
 * @param address
 * @return <code>Criterion</code>
 */
public static Criterion address(AddressType type, String address) {
  return new HeaderCriterion(type.name(), new AddressOperator(address));
}

  private MessageAttachment createAttachment() {
    return MessageAttachment.builder()
      .attachment(Attachment.builder()
        .bytes("content".getBytes(StandardCharsets.UTF_8))
        .type("type")
        .build())
      .build();
  }
}

/**
 * Return a read-only {@link Iterator} which contains all uid which fall in the specified range.
 */
@Override
public Iterator<MessageUid> iterator() {
  return new RangeIterator(getUidFrom(), getUidTo());
}

public MessageParser() {
  cidParser = Cid.parser()
    .relaxed()
    .unwrap();
}

@Override
public long size() throws MailboxException {
  return result.getHeaders().size();
}

public static <U extends QuotaValue<U>> SerializableQuota<U> newInstance(U used, U max) {
  return new SerializableQuota<>(
    new SerializableQuotaValue<>(used),
    new SerializableQuotaValue<>(max)
  );
}

@Override
public  Optional<Cid> apply(CidValidator cidValidator, String value) {
  cidValidator.validate(value);
  if (isWrappedWithAngleBrackets(value)) {
    return unwrap(value, cidValidator);
  }
  return toCid(cidValidator, value);
}

/**
 * Creates a filter for message size less than the given value
 * 
 * @param value
 *            messages with size less than this value will be selected by
 *            the returned criterion
 * @return <code>Criterion</code>, not null
 */
public static Criterion sizeLessThan(long value) {
  return new SizeCriterion(new NumericOperator(value, NumericComparator.LESS_THAN));
}

/**
 * Creates a filter for message mod-sequence greater than the given value
 * 
 * @param value
 *            messages with mod-sequence greater than this value will be
 *            selected by the returned criterion
 * @return <code>Criterion</code>, not null
 */
public static Criterion modSeqGreaterThan(long value) {
  return new ModSeqCriterion(new NumericOperator(value, NumericComparator.GREATER_THAN));
}

/**
 * Creates a filter on the given flag selecting messages where the given
 * flag is not selected.
 * 
 * @param flag
 *            <code>Flag</code>, not null
 * @return <code>Criterion</code>, not null
 */
public static Criterion flagIsUnSet(String flag) {
  return new CustomFlagCriterion(flag, BooleanOperator.unset());
}

/**
 * Creates a filter on the given flag selecting messages where the given
 * flag is selected.
 * 
 * @param flag
 *            <code>Flag</code>, not null
 * @return <code>Criterion</code>, not null
 */
public static Criterion flagIsSet(Flag flag) {
  return new FlagCriterion(flag, BooleanOperator.set());
}

/**
 * Creates a filter on the given flag selecting messages where the given
 * flag is selected.
 * 
 * @param flag
 *            <code>Flag</code>, not null
 * @return <code>Criterion</code>, not null
 */
public static Criterion flagIsSet(String flag) {
  return new CustomFlagCriterion(flag, BooleanOperator.set());
}

/**
 * Creates a filter on the given flag selecting messages where the given
 * flag is not selected.
 * 
 * @param flag
 *            <code>Flag</code>, not null
 * @return <code>Criterion</code>, not null
 */
public static Criterion flagIsUnSet(Flag flag) {
  return new FlagCriterion(flag, BooleanOperator.unset());
}

/**
 * Creates a filter matching messages with a header matching the given name.
 * 
 * All to-compared Strings MUST BE converted to uppercase before doing so
 * (this also include the search value)
 * 
 * @param headerName
 *            name of the header whose value will be compared, not null
 * @return <code>Criterion</code>, not null
 */
public static Criterion headerExists(String headerName) {
  return new HeaderCriterion(headerName, ExistsOperator.exists());
}

/**
 * Creates a filter for message size greater than the given value
 * 
 * @param value
 *            messages with size greater than this value will be selected by
 *            the returned criterion
 * @return <code>Criterion</code>, not null
 */
public static Criterion sizeGreaterThan(long value) {
  return new SizeCriterion(new NumericOperator(value, NumericComparator.GREATER_THAN));
}

/**
 * Creates a filter for message mod-sequence less than the given value
 * 
 * @param value
 *            messages with mod-sequence less than this value will be
 *            selected by the returned criterion
 * @return <code>Criterion</code>, not null
 */
public static Criterion modSeqLessThan(long value) {
  return new ModSeqCriterion(new NumericOperator(value, NumericComparator.LESS_THAN));
}

/**
 * Creates a filter for message size equal to the given value
 * 
 * @param value
 *            messages with size equal to this value will be selected by the
 *            returned criterion
 * @return <code>Criterion</code>, not null
 */
public static Criterion sizeEquals(long value) {
  return new SizeCriterion(new NumericOperator(value, NumericComparator.EQUALS));
}

/**
 * Creates a filter for message mod-sequence equal to the given value
 * 
 * @param value
 *            messages with mod-sequence equal to this value will be
 *            selected by the returned criterion
 * @return <code>Criterion</code>, not null
 */
public static Criterion modSeqEquals(long value) {
  return new ModSeqCriterion(new NumericOperator(value, NumericComparator.EQUALS));
}