添加 OptionalUtil。

src/main/java/xyz/zhouxy/plusone/commons/util/OptionalUtil.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright 2022-2023 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package xyz.zhouxy.plusone.commons.util;
+
+import java.util.Optional;
+import java.util.OptionalDouble;
+import java.util.OptionalInt;
+import java.util.OptionalLong;
+
+import javax.annotation.Nullable;
+
+/**
+ * OptionalUtil
+ *
+ * <p>
+ * 提供一些 Optional 相关的方法
+ *
+ * @author <a href="https://gitee.com/zhouxy108">ZhouXY</a>
+ * @since 0.1.0
+ * @see Optional
+ * @see OptionalInt
+ * @see OptionalLong
+ * @see OptionalDouble
+ */
+public class OptionalUtil {
+
+    public static OptionalInt optionalOf(@Nullable Integer value) {
+        return value != null ? OptionalInt.of(value) : OptionalInt.empty();
+    }
+
+    public static OptionalInt toOptionalInt(Optional<Integer> objectOptional) {
+        return optionalOf(objectOptional.orElse(null));
+    }
+
+    public static OptionalLong optionalOf(@Nullable Long value) {
+        return value != null ? OptionalLong.of(value) : OptionalLong.empty();
+    }
+
+    public static OptionalLong toOptionalLong(Optional<Long> objectOptional) {
+        return optionalOf(objectOptional.orElse(null));
+    }
+
+    public static OptionalDouble optionalOf(@Nullable Double value) {
+        return value != null ? OptionalDouble.of(value) : OptionalDouble.empty();
+    }
+
+    public static OptionalDouble toOptionalDouble(Optional<Double> objectOptional) {
+        return optionalOf(objectOptional.orElse(null));
+    }
+
+    private OptionalUtil() {
+        throw new IllegalStateException("Utility class");
+    }
+}