fix nullability issue

Author: SirCotare

src/main/java/it/aboutbits/springboot/toolbox/util/CollectUtil.java

@@ -1,7 +1,6 @@
 package it.aboutbits.springboot.toolbox.util;
 
 import org.jspecify.annotations.NullMarked;
-import org.jspecify.annotations.Nullable;
 import org.springframework.data.util.Streamable;
 
 import java.util.Collection;
@@ -94,12 +93,11 @@ public static <T, R> Stream<R> collectToStream(Stream<T> items, NullableFunction
     }
 
     public static <T, K, R> Map<K, R> collectToMap(
-            Collection<@Nullable T> items,
+            Collection<T> items,
             Function<T, K> keyMapper,
             Function<T, R> valueMapper
     ) {
         return items.stream()
-                .filter(Objects::nonNull)
                 .collect(Collectors.toMap(keyMapper, valueMapper));
     }
 
@@ -113,12 +111,11 @@ public static <T, K, R> Map<K, R> collectToMap(
     }
 
     public static <T, K, R> Map<K, R> collectToMap(
-            Stream<@Nullable T> items,
+            Stream<T> items,
             Function<T, K> keyMapper,
             Function<T, R> valueMapper
     ) {
         return items
-                .filter(Objects::nonNull)
                 .collect(Collectors.toMap(keyMapper, valueMapper));
     }
 }

src/test/java/it/aboutbits/springboot/toolbox/util/CollectUtilTest.java

@@ -1,7 +1,6 @@
 package it.aboutbits.springboot.toolbox.util;
 
 import org.jspecify.annotations.NullMarked;
-import org.jspecify.annotations.Nullable;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Nested;
 import org.junit.jupiter.api.Test;
@@ -381,7 +380,7 @@ class CollectToMap {
         @DisplayName("Should convert Collection to Map using key and value mappers")
         void shouldConvertCollectionToMapUsingMappers() {
             // given
-            var items = (Collection<@Nullable String>) Arrays.asList("a", "bb", "ccc");
+            var items = (Collection<String>) Arrays.asList("a", "bb", "ccc");
 
             // when
             var result = CollectUtil.collectToMap(items, String::length, Function.identity());
@@ -398,7 +397,7 @@ void shouldConvertCollectionToMapUsingMappers() {
         @DisplayName("Should throw on duplicate keys according to Collectors.toMap default behavior")
         void shouldThrowOnDuplicateKeys() {
             // given
-            var items = (Collection<@Nullable String>) Arrays.asList("a", "b"); // both have length of 1
+            var items = (Collection<String>) Arrays.asList("a", "b"); // both have length of 1
 
             // when / then
             assertThatIllegalStateException().isThrownBy(
@@ -431,7 +430,7 @@ void shouldConvertStreamableToMapUsingMappers() {
         @DisplayName("Should convert Stream to Map using key and value mappers")
         void shouldConvertStreamToMapUsingMappers() {
             // given
-            var items = Stream.<@Nullable String>of("m", "nn");
+            var items = Stream.of("m", "nn");
 
             // when
             var result = CollectUtil.collectToMap(items, String::length, Function.identity());
@@ -447,7 +446,7 @@ void shouldConvertStreamToMapUsingMappers() {
         @DisplayName("Should return empty map for empty collection")
         void shouldReturnEmptyMapForEmptyCollection() {
             // given
-            var items = Collections.<@Nullable String>emptyList();
+            var items = Collections.<String>emptyList();
 
             // when
             var result = CollectUtil.collectToMap(items, String::length, Function.identity());
@@ -473,7 +472,7 @@ void shouldReturnEmptyMapForEmptyStreamable() {
         @DisplayName("Should return empty map for empty stream")
         void shouldReturnEmptyMapForEmptyStream() {
             // given
-            var items = Stream.<@Nullable String>empty();
+            var items = Stream.<String>empty();
 
             // when
             var result = CollectUtil.collectToMap(items, String::length, Function.identity());