add ObjectUtils.getNonNull/getIfNull/getIfEmpty

spring-core/src/main/java/org/springframework/util/ObjectUtils.java

@@ -118,6 +118,49 @@ public static boolean isEmpty(@Nullable Object @Nullable [] array) {
 		return (array == null || array.length == 0);
 	}
 
+
+	/**
+	 * Returns the first non-null element from the provided varargs.
+	 *
+	 * @param objects The objects to check for non-null values.
+	 * @param <T>     The type of the objects.
+	 * @return An Optional containing the first non-null object, or an empty Optional if all objects are null.
+	 */
+	@SafeVarargs
+	public static <T> Optional<T> getNonNull(@Nullable final T... objects) {
+		return Optional.ofNullable(objects)
+				.map(arr -> Arrays.stream(arr).filter(Objects::nonNull).findFirst())
+				.orElse(Optional.empty());
+	}
+
+	/**
+	 * Returns the object if it is not {@code null}; otherwise, returns the default value.
+	 *
+	 * @param object       the object to test, may be {@code null}
+	 * @param defaultValue the default value to return if the object is {@code null}, may be {@code null}
+	 * @param <T>          the type of the object
+	 * @return An Optional containing either the object if not null, or the default value wrapped in an Optional.
+	 */
+	public static <T> Optional<T> getIfNull(@Nullable final T object, @Nullable final T defaultValue) {
+		return Optional.ofNullable(object).or(() -> Optional.ofNullable(defaultValue));
+	}
+
+	/**
+	 * Returns the collection if it is not {@code null} and not empty; otherwise, returns the default value.
+	 *
+	 * @param object       the collection to test, may be {@code null}
+	 * @param defaultValue the default value to return if the collection is {@code null} or empty, may be {@code null}
+	 * @param <T>          the type of elements in the collection
+	 * @return An Optional containing the collection if not null and not empty, otherwise an Optional of the default
+	 * value.
+	 */
+	public static <T> Optional<Collection<T>> getIfEmpty(@Nullable final Collection<T> object,
+														 @Nullable final Collection<T> defaultValue) {
+		return Optional.ofNullable(object)
+				.filter(collection -> !collection.isEmpty())
+				.or(() -> Optional.ofNullable(defaultValue));
+	}
+
 	/**
 	 * Determine whether the given object is empty.
 	 * <p>This method supports the following object types.

spring-core/src/test/java/org/springframework/util/ObjectUtilsTests.java

@@ -31,6 +31,7 @@
 import java.time.LocalDate;
 import java.time.ZoneId;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Collections;
 import java.util.Currency;
 import java.util.Date;
@@ -52,6 +53,9 @@
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+import static org.springframework.util.ObjectUtils.getIfEmpty;
+import static org.springframework.util.ObjectUtils.getIfNull;
+import static org.springframework.util.ObjectUtils.getNonNull;
 import static org.springframework.util.ObjectUtils.isEmpty;
 
 /**
@@ -111,6 +115,55 @@ void isCompatibleWithThrowsClause() {
 		assertThat(ObjectUtils.isCompatibleWithThrowsClause(new Throwable(), throwable)).isTrue();
 	}
 
+	@Test
+	void getIfNullObject() {
+		String value = UUID.randomUUID().toString();
+		String backup = UUID.randomUUID().toString();
+
+		assertThat(getIfNull(value, backup)).contains(value);
+		assertThat(getIfNull(value, backup)).contains(value);
+		assertThat(getIfNull(value, value)).contains(value);
+		assertThat(getIfNull(backup, backup)).contains(backup);
+		assertThat(getIfNull(null, value)).contains(value);
+		assertThat(getIfNull(null, backup)).contains(backup);
+		assertThat(getIfNull("null", backup)).contains("null");
+		assertThat(getIfNull(null, null)).isEmpty();
+	}
+
+	@Test
+	void getIfEmptyObject() {
+		Collection<String> empty = Collections.emptyList();
+		Collection<String> value = List.of(UUID.randomUUID().toString());
+		Collection<String> backup = List.of(UUID.randomUUID().toString());
+
+		assertThat(getIfEmpty(value, backup)).contains(value);
+		assertThat(getIfEmpty(null, backup)).contains(backup);
+		assertThat(getIfEmpty(empty, backup)).contains(backup);
+		assertThat(getIfEmpty(value, empty)).contains(value);
+		assertThat(getIfEmpty(empty, empty)).contains(empty);
+		assertThat(getIfEmpty(backup, backup)).contains(backup);
+		assertThat(getIfEmpty(null, empty)).contains(empty);
+		assertThat(getIfEmpty(null, backup)).contains(backup);
+		assertThat(getIfEmpty(null, null)).isEmpty();
+	}
+
+	@Test
+	void getNonNullObject() {
+		String value = UUID.randomUUID().toString();
+		String backup = UUID.randomUUID().toString();
+
+		assertThat(getNonNull(backup, value, value)).contains(backup);
+		assertThat(getNonNull(value, null, backup)).contains(value);
+		assertThat(getNonNull(backup, value, null)).contains(backup);
+		assertThat(getNonNull(value, backup)).contains(value);
+		assertThat(getNonNull(null, null, value)).contains(value);
+
+		String _null = null;
+		assertThat(getNonNull(null, null, _null)).isEmpty();
+		assertThat(getNonNull(null, "null", backup)).contains("null");
+		assertThat(getNonNull(null, null)).isEmpty();
+	}
+
 	@Test
 	void isEmptyNull() {
 		assertThat(isEmpty(null)).isTrue();