feat: 加入集合环形索引获取工具类RingIndexUtil

加入集合环形索引获取工具类RingIndexUtil

hutool-core/src/test/java/cn/hutool/core/collection/RingIndexUtilTest.java

@@ -0,0 +1,51 @@
+package cn.hutool.core.collection;
+
+import cn.hutool.core.thread.ThreadUtil;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.atomic.AtomicLong;
+
+/**
+ * 集合索引环形获取工具类测试类
+ *
+ * @author ZhouChuGang
+ * @version 1.0
+ * @project hutool
+ * @date 2021/10/13 18:47
+ */
+public class RingIndexUtilTest {
+
+	private final List<String> strList = Arrays.asList("0", "1", "2", "3", "4", "5", "6", "7", "8", "9");
+
+	/**
+	 * 观察输出的打印为不重复的
+	 */
+	@Test
+	public void ringNextLongByObjTest() {
+		final AtomicLong atomicLong = new AtomicLong();
+		// 开启并发测试，每个线程获取到的元素都是唯一的
+		ThreadUtil.concurrencyTest(strList.size(), () -> {
+			final long index = RingIndexUtil.ringNextLongByObj(strList, atomicLong);
+			final String s = strList.get((int) index);
+			System.out.println(s);
+		});
+	}
+
+	/**
+	 * 观察输出的打印为不重复的
+	 */
+	@Test
+	public void ringNextIntByObjTest() {
+		final AtomicInteger atomicInteger = new AtomicInteger();
+		// 开启并发测试，每个线程获取到的元素都是唯一的
+		ThreadUtil.concurrencyTest(strList.size(), () -> {
+			final int index = RingIndexUtil.ringNextIntByObj(strList, atomicInteger);
+			final String s = strList.get(index);
+			System.out.println(s);
+		});
+	}
+
+}