Removed BagTypeAdapter in favor of Container1TypeAdapter and Containe…

…r2TypeAdapter

src/main/java/lsh/ext/gson/ITypeAdapterFactory.java

@@ -25,6 +25,8 @@ interface ITypeResolver<K> {
 
 		<T> TypeAdapter<T> getTypeAdapter(int index);
 
+		<T> TypeAdapter<T> getTypeAdapterForClass(Class<T> klass);
+
 	}
 
 	@SuppressWarnings("NewClassNamingConvention")
@@ -58,6 +60,11 @@ public <INNER_T> TypeAdapter<INNER_T> getTypeAdapter(final int index) {
 						final TypeToken<INNER_T> o = (TypeToken<INNER_T>) TypeToken.get(typeArgument);
 						return gson.getAdapter(o);
 					}
+
+					@Override
+					public <T> TypeAdapter<T> getTypeAdapterForClass(final Class<T> klass) {
+						return gson.getAdapter(klass);
+					}
 				};
 				@SuppressWarnings("unchecked")
 				final TypeAdapter<T> castTypeAdapter = (TypeAdapter<T>) createTypeAdapter.apply(typeResolver);
@@ -97,6 +104,11 @@ public <INNER_T> TypeAdapter<INNER_T> getTypeAdapter(final int index) {
 						final TypeToken<INNER_T> o = (TypeToken<INNER_T>) TypeToken.get(typeArgument);
 						return gson.getAdapter(o);
 					}
+
+					@Override
+					public <T> TypeAdapter<T> getTypeAdapterForClass(final Class<T> klass) {
+						return gson.getAdapter(klass);
+					}
 				};
 				@SuppressWarnings("unchecked")
 				final TypeAdapter<T> castTypeAdapter = (TypeAdapter<T>) createTypeAdapter.apply(typeResolver);

src/main/java/lsh/ext/gson/ext/org/apache/commons/collections4/ApacheCommonsCollections4TypeAdapter.java

@@ -1,5 +1,6 @@
 package lsh.ext.gson.ext.org.apache.commons.collections4;
 
+import java.util.AbstractMap;
 import java.util.Map;
 import java.util.function.Function;
 import java.util.function.Supplier;
@@ -12,18 +13,45 @@
 import lsh.ext.gson.IBuilder2;
 import org.apache.commons.collections4.Bag;
 import org.apache.commons.collections4.BidiMap;
+import org.apache.commons.collections4.IteratorUtils;
 import org.apache.commons.collections4.MultiSet;
 import org.apache.commons.collections4.MultiValuedMap;
 
 @UtilityClass
 public final class ApacheCommonsCollections4TypeAdapter {
 
 	public static <E> TypeAdapter<Bag<E>> forBag(
+			final TypeAdapter<E> typeAdapter,
+			final Supplier<? extends IBuilder1<? super E, ? extends Bag<E>>> builderFactory
+	) {
+		return Container1TypeAdapter.getInstance(typeAdapter, Bag::iterator, builderFactory);
+	}
+
+	public static TypeAdapter<Bag<String>> forBagNCopies(
+			final TypeAdapter<Integer> integerTypeAdapter,
+			final Supplier<? extends IBuilder2<? super String, ? super Integer, ? extends Bag<String>>> builderFactory
+	) {
+		return forBagNCopies(integerTypeAdapter, builderFactory, Function.identity(), Function.identity());
+	}
+
+	public static <E> TypeAdapter<Bag<E>> forBagNCopies(
+			final TypeAdapter<Integer> integerTypeAdapter,
 			final Supplier<? extends IBuilder2<? super E, ? super Integer, ? extends Bag<E>>> builderFactory,
 			final Function<? super E, String> toName,
 			final Function<? super String, ? extends E> fromName
 	) {
-		return BagTypeAdapter.getInstance(builderFactory, toName, fromName);
+		return Container2TypeAdapter.<E, Integer, Bag<E>, Map.Entry<String, Integer>>getInstance(
+				integerTypeAdapter,
+				es -> IteratorUtils.transformedIterator(
+						es.uniqueSet().iterator(),
+						e -> new AbstractMap.SimpleImmutableEntry<>(toName.apply(e), es.getCount(e))
+				),
+				e -> fromName.apply(e.getKey()),
+				Map.Entry::getValue,
+				toName,
+				fromName,
+				builderFactory
+		);
 	}
 
 	public static <V> TypeAdapter<BidiMap<String, V>> forBidiMap(

src/main/java/lsh/ext/gson/ext/org/apache/commons/collections4/ApacheCommonsCollections4TypeAdapterFactory.java

@@ -4,6 +4,7 @@
 import java.util.function.Supplier;
 
 import com.google.common.collect.BiMap;
+import com.google.gson.TypeAdapter;
 import com.google.gson.reflect.TypeToken;
 import lombok.experimental.UtilityClass;
 import lsh.ext.gson.IBuilder1;
@@ -36,17 +37,28 @@ public static <E> ITypeAdapterFactory<Bag<E>> forBag(
 			final Function<? super E, String> toKey,
 			final Function<? super String, ? extends E> fromKey
 	) {
-		return ITypeAdapterFactory.forClassHierarchy(Bag.class, typeResolver -> ApacheCommonsCollections4TypeAdapter.forBag(lookup.lookup(typeResolver.getTypeToken()), toKey, fromKey));
+		return ITypeAdapterFactory.forClassHierarchy(
+				Bag.class,
+				typeResolver -> {
+					final TypeAdapter<Integer> integerTypeAdapter = typeResolver.getTypeAdapterForClass(int.class);
+					return ApacheCommonsCollections4TypeAdapter.forBagNCopies(
+							integerTypeAdapter,
+							lookup.lookup(typeResolver.getTypeToken()),
+							toKey,
+							fromKey
+					);
+				}
+		);
 	}
 
 	// TODO handle all known implementations
 	public static <E> Supplier<IBuilder2<E, Integer, Bag<E>>> defaultBuilderForBag(final TypeToken<? super Bag<E>> typeToken) {
 		@SuppressWarnings("unchecked")
 		final Class<? super Bag<?>> rawType = (Class<? super Bag<?>>) typeToken.getRawType();
 		if ( HashBag.class.isAssignableFrom(rawType) ) {
-			return () -> Builder.forBag(new HashBag<>());
+			return () -> Builder.forBagNCopies(HashBag::new);
 		}
-		return () -> Builder.forBag(new HashBag<>());
+		return () -> Builder.forBagNCopies(HashBag::new);
 	}
 
 	public static final ITypeAdapterFactory<BidiMap<String, Object>> defaultForBidiMap = forBidiMap(ApacheCommonsCollections4TypeAdapterFactory::defaultBuilderForBidiMap);
@@ -117,12 +129,12 @@ public static <V> Supplier<IBuilder2<String, V, MultiValuedMap<String, V>>> defa
 		@SuppressWarnings("unchecked")
 		final Class<? extends MultiValuedMap<?, ?>> rawType = (Class<? extends MultiValuedMap<?, ?>>) typeToken.getRawType();
 		if ( ArrayListValuedHashMap.class.isAssignableFrom(rawType) ) {
-			return () -> Builder.forMultiValuedMap(new ArrayListValuedHashMap<>());
+			return () -> Builder.forMultiValuedMap(ArrayListValuedHashMap::new);
 		}
 		if ( HashSetValuedHashMap.class.isAssignableFrom(rawType) ) {
-			return () -> Builder.forMultiValuedMap(new HashSetValuedHashMap<>());
+			return () -> Builder.forMultiValuedMap(HashSetValuedHashMap::new);
 		}
-		return () -> Builder.forMultiValuedMap(new ArrayListValuedHashMap<>());
+		return () -> Builder.forMultiValuedMap(ArrayListValuedHashMap::new);
 	}
 
 }

src/main/java/lsh/ext/gson/ext/org/apache/commons/collections4/Builder.java

@@ -1,39 +1,26 @@
 package lsh.ext.gson.ext.org.apache.commons.collections4;
 
+import java.util.function.Supplier;
+
 import lombok.experimental.UtilityClass;
+import lsh.ext.gson.IBuilder1;
 import lsh.ext.gson.IBuilder2;
 import org.apache.commons.collections4.Bag;
 import org.apache.commons.collections4.MultiValuedMap;
 
 @UtilityClass
 public final class Builder {
 
-	public static <E, B extends Bag<E>> IBuilder2<E, Integer, B> forBag(final B bag) {
-		return new IBuilder2<>() {
-			@Override
-			public void accept(final E e, final Integer n) {
-				bag.add(e, n);
-			}
-
-			@Override
-			public B build() {
-				return bag;
-			}
-		};
+	public static <E, B extends Bag<E>> IBuilder1<E, B> forBag(final Supplier<? extends B> create) {
+		return IBuilder1.of(create, (e, bag) -> bag.add(e));
 	}
 
-	public static <K, V, M extends MultiValuedMap<K, V>> IBuilder2<K, V, M> forMultiValuedMap(final M multiValuedMap) {
-		return new IBuilder2<>() {
-			@Override
-			public void accept(final K k, final V v) {
-				multiValuedMap.put(k, v);
-			}
+	public static <E, B extends Bag<E>> IBuilder2<E, Integer, B> forBagNCopies(final Supplier<? extends B> create) {
+		return IBuilder2.of(create, (e, nCopies, bag) -> bag.add(e, nCopies));
+	}
 
-			@Override
-			public M build() {
-				return multiValuedMap;
-			}
-		};
+	public static <K, V, M extends MultiValuedMap<K, V>> IBuilder2<K, V, M> forMultiValuedMap(final Supplier<? extends M> create) {
+		return IBuilder2.of(create, (k, v, map) -> map.put(k, v));
 	}
 
 }

src/test/java/lsh/ext/gson/ext/org/apache/commons/collections4/ApacheCommonsCollections4TypeAdapterTest.java

@@ -0,0 +1,57 @@
+package lsh.ext.gson.ext.org.apache.commons.collections4;
+
+import java.io.IOException;
+import java.util.function.Function;
+
+import com.google.gson.TypeAdapter;
+import lsh.ext.gson.IBuilder2;
+import lsh.ext.gson.test.TestTypeAdapters;
+import org.apache.commons.collections4.Bag;
+import org.apache.commons.collections4.bag.TreeBag;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public final class ApacheCommonsCollections4TypeAdapterTest {
+
+	@Test
+	public void testForBagRoundTrip()
+			throws IOException {
+		final TypeAdapter<Bag<String>> unit = ApacheCommonsCollections4TypeAdapter.forBag(
+				TestTypeAdapters.stringTypeAdapter,
+				() -> Builder.forBag(TreeBag::new)
+		);
+		final Bag<String> before = new TreeBag<>();
+		before.add("foo");
+		before.add("bar");
+		before.add("bar");
+		before.add("baz");
+		before.add("baz");
+		before.add("baz");
+		final String json = unit.toJson(before);
+		Assertions.assertEquals("[\"bar\",\"bar\",\"baz\",\"baz\",\"baz\",\"foo\"]", json);
+		final Bag<String> actual = unit.fromJson(json);
+		Assertions.assertIterableEquals(before, actual);
+	}
+
+	@Test
+	public void testForBagNCopiesForRoundTrip()
+			throws IOException {
+		@SuppressWarnings("RedundantTypeArguments")
+		final TypeAdapter<Bag<String>> unit = ApacheCommonsCollections4TypeAdapter.<String>forBagNCopies(
+				TestTypeAdapters.integerTypeAdapter,
+				() -> IBuilder2.of(TreeBag::new, (e, nCopies, strings) -> strings.add(e, nCopies), Function.identity())
+		);
+		final Bag<String> before = new TreeBag<>();
+		before.add("foo");
+		before.add("bar");
+		before.add("bar");
+		before.add("baz");
+		before.add("baz");
+		before.add("baz");
+		final String json = unit.toJson(before);
+		Assertions.assertEquals("{\"bar\":2,\"baz\":3,\"foo\":1}", json);
+		final Bag<String> actual = unit.fromJson(json);
+		Assertions.assertIterableEquals(before, actual);
+	}
+
+}