/**
* Adds a fragment to the assembler.
*
* @param fragment An AIS message fragment
* @return an assembled message or null if the message is not complete
*/
public RawMessage addFragment(final Fragment fragment) {
final int actualFragment = fragment.getCurrentFragment();
final int totalFragments = fragment.getTotalFragments();
final int expectedFragment = fragments.size() + 1;
if (actualFragment == expectedFragment) {
fragments.add(fragment);
} else {
fragments.clear();
if (actualFragment == 1) {
fragments.add(fragment);
}
}
RawMessage message = null;
if (totalFragments == fragments.size()) {
message = new RawMessage();
message.setFragments(new ArrayList<Fragment>(fragments));
message.setBinary(getBinaryPayload());
fragments.clear();
}
return message;
}
