添加注解选择器

hutool-core/src/main/java/cn/hutool/core/annotation/SynthesizedAnnotationSelector.java

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+package cn.hutool.core.annotation;
+
+/**
+ * 注解选择器，指定两个注解，选择其中一个返回。<br>
+ * 该接口用于在{@link SyntheticAnnotation}中用于从一批相同的注解对象中筛选最终用于合成注解对象。
+ *
+ * @author huangchengxing
+ */
+@FunctionalInterface
+public interface SynthesizedAnnotationSelector {
+
+	/**
+	 * 返回距离根对象更近的注解，当距离一样时优先返回旧注解
+	 */
+	SynthesizedAnnotationSelector NEAREST_AND_OLDEST_PRIORITY = new NearestAndOldestPrioritySelector();
+
+	/**
+	 * 返回距离根对象更近的注解，当距离一样时优先返回新注解
+	 */
+	SynthesizedAnnotationSelector NEAREST_AND_NEWEST_PRIORITY = new NearestAndNewestPrioritySelector();
+
+	/**
+	 * 返回距离根对象更远的注解，当距离一样时优先返回旧注解
+	 */
+	SynthesizedAnnotationSelector FARTHEST_AND_OLDEST_PRIORITY = new FarthestAndOldestPrioritySelector();
+
+	/**
+	 * 返回距离根对象更远的注解，当距离一样时优先返回新注解
+	 */
+	SynthesizedAnnotationSelector FARTHEST_AND_NEWEST_PRIORITY = new FarthestAndNewestPrioritySelector();
+
+	/**
+	 * 比较两个被合成的注解，选择其中的一个并返回
+	 *
+	 * @param oldAnnotation 已存在的注解，该参数不允许为空
+	 * @param newAnnotation 新获取的注解，该参数不允许为空
+	 * @return 被合成的注解
+	 */
+	<T, A extends SynthesizedAnnotation<T>> A choose(A oldAnnotation, A newAnnotation);
+
+	/**
+	 * 返回距离根对象更近的注解，当距离一样时优先返回旧注解
+	 */
+	class NearestAndOldestPrioritySelector implements SynthesizedAnnotationSelector {
+		@Override
+		public <T, A extends SynthesizedAnnotation<T>> A choose(A oldAnnotation, A newAnnotation) {
+			return newAnnotation.getVerticalDistance() < oldAnnotation.getVerticalDistance() ? newAnnotation : oldAnnotation;
+		}
+	}
+
+	/**
+	 * 返回距离根对象更近的注解，当距离一样时优先返回新注解
+	 */
+	class NearestAndNewestPrioritySelector implements SynthesizedAnnotationSelector {
+		@Override
+		public <T, A extends SynthesizedAnnotation<T>> A choose(A oldAnnotation, A newAnnotation) {
+			return newAnnotation.getVerticalDistance() <= oldAnnotation.getVerticalDistance() ? newAnnotation : oldAnnotation;
+		}
+	}
+
+	/**
+	 * 返回距离根对象更远的注解，当距离一样时优先返回旧注解
+	 */
+	class FarthestAndOldestPrioritySelector implements SynthesizedAnnotationSelector {
+		@Override
+		public <T, A extends SynthesizedAnnotation<T>> A choose(A oldAnnotation, A newAnnotation) {
+			return newAnnotation.getVerticalDistance() > oldAnnotation.getVerticalDistance() ? newAnnotation : oldAnnotation;
+		}
+	}
+
+	/**
+	 * 返回距离根对象更远的注解，当距离一样时优先返回新注解
+	 */
+	class FarthestAndNewestPrioritySelector implements SynthesizedAnnotationSelector {
+		@Override
+		public <T, A extends SynthesizedAnnotation<T>> A choose(A oldAnnotation, A newAnnotation) {
+			return newAnnotation.getVerticalDistance() >= oldAnnotation.getVerticalDistance() ? newAnnotation : oldAnnotation;
+		}
+	}
+
+}