@Test
public void one_to_many_join() {
Record joined =
RecordJoins.join(authors)
.on(id)
.to(authorId)
.oneToMany(books, authored)
.filter(authorName.is("Alan Goodyear"))
.findFirst()
.get();
assertThat(authored.extract(joined), hasItems(cromulenceOfTruths, amorousEncounters));
}
@Test
public void three_way_join() {
List<Record> joined =
RecordJoins.join(RecordJoins.join(books).on(authorId).to(id).manyToOne(authors))
.on(publisherId)
.to(id)
.manyToOne(publishers)
.map(r -> r.select(publisherName, authorName, bookName))
.filter(authorName.is("Alan Goodyear"))
.collect(Collectors.toList());
assertThat(
joined,
CoreMatchers.hasItems(
$$(
bookName.of("Amorous Encounters"),
authorName.of("Alan Goodyear"),
publisherName.of("Bills And Moon")),
$$(
bookName.of("The Cromulence Of Truths"),
authorName.of("Alan Goodyear"),
publisherName.of("Servo"))));
}
public <V> Builder writeToString(Key<V> key, Function<V, String> converter) {
return writeToString(key, key.name(), converter);
}
public <V> Builder write(
Key<? extends V> key, BiConsumer<JsonGenerator, ? super V> serialiser) {
return write(key, key.name(), serialiser);
}
public class RecordJoinerTest {
public static final Key<String> authorName = $("authorName");
public static final Key<String> id = $("id");
public static final Key<String> authorId = $("authorId");
public static final Key<String> bookName = $("bookName");
public static final Key<String> publisherName = $("publisherName");
public static final Key<String> publisherId = $("publisherId");
public static final Record billsAndMoon = $$(publisherName.of("Bills And Moon"), id.of("BM"));
public static final Record servo = $$(publisherName.of("Servo"), id.of("SV"));
public static final List<Record> publishers = Arrays.asList(billsAndMoon, servo);
public static final Record alanGoodyear = $$(authorName.of("Alan Goodyear"), id.of("AG"));
public static final Record barbaraMoat = $$(authorName.of("Barbara Moat"), id.of("BM"));
public static final Record leavisLacanian = $$(authorName.of("Leavis Lacanian"), id.of("LL"));
public static final List<Record> authors =
Arrays.asList(alanGoodyear, barbaraMoat, leavisLacanian);
public static final Record cromulenceOfTruths =
$$(authorId.of("AG"), publisherId.of("SV"), bookName.of("The Cromulence Of Truths"));
public static final Record oligarchsSecret =
$$(authorId.of("BM"), publisherId.of("BM"), bookName.of("Oligarch's Secret"));
public static final Record butIsThisNot =
$$(
authorId.of("LL"),
publisherId.of("SV"),
bookName.of("But Is This Not: Dialectics for the Distracted"));
public static final Record amorousEncounters =
$$(authorId.of("AG"), publisherId.of("BM"), bookName.of("Amorous Encounters"));
public static final List<Record> books =
Arrays.asList(cromulenceOfTruths, oligarchsSecret, butIsThisNot, amorousEncounters);
final ListKey<Record> authored = $L("authored");
@Test
public void three_way_join() {
List<Record> joined =
RecordJoins.join(RecordJoins.join(books).on(authorId).to(id).manyToOne(authors))
.on(publisherId)
.to(id)
.manyToOne(publishers)
.map(r -> r.select(publisherName, authorName, bookName))
.filter(authorName.is("Alan Goodyear"))
.collect(Collectors.toList());
assertThat(
joined,
CoreMatchers.hasItems(
$$(
bookName.of("Amorous Encounters"),
authorName.of("Alan Goodyear"),
publisherName.of("Bills And Moon")),
$$(
bookName.of("The Cromulence Of Truths"),
authorName.of("Alan Goodyear"),
publisherName.of("Servo"))));
}
@Test
public void one_to_many_join() {
Record joined =
RecordJoins.join(authors)
.on(id)
.to(authorId)
.oneToMany(books, authored)
.filter(authorName.is("Alan Goodyear"))
.findFirst()
.get();
assertThat(authored.extract(joined), hasItems(cromulenceOfTruths, amorousEncounters));
}
}