!1021 重试工具类添加

Merge pull request !1021 from 孔皮皮/v6-dev-retry

hutool-core/src/test/java/org/dromara/hutool/core/util/RetryUtilTest.java

@@ -0,0 +1,75 @@
+package org.dromara.hutool.core.util;
+
+import org.dromara.hutool.core.thread.RetryableTask;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import java.time.Duration;
+import java.util.concurrent.CompletableFuture;
+
+public class RetryUtilTest {
+
+	@Test
+	void test() {
+		//自定义根据异常重试
+		CompletableFuture<RetryableTask<String>> task = RetryableTask.retryForExceptions(() -> {
+				System.out.println("1231231");
+				int a = 1 / 0;
+				return "qqqq";
+			}, ArithmeticException.class)
+			.delay(Duration.ofSeconds(1))
+			.maxAttempts(3)
+			.asyncExecute();
+
+		Assertions.assertFalse(task.isDone());
+		Assertions.assertEquals("兜底", task.join().get().orElseGet(() -> {
+			return "兜底";
+		}));
+		Assertions.assertTrue(task.isDone());
+
+	}
+
+	@Test
+	public void noReturnTest() {
+		//根据异常重试，没有返回值
+		RetryUtil.ofException(
+			() -> {
+				System.out.println(123);
+				int a = 1 / 0;
+			},
+			3,
+			Duration.ofSeconds(1),
+			() -> {
+				System.out.println("兜底");
+			},
+			ArithmeticException.class
+		);
+	}
+
+
+	@Test
+	public void hasReturnTest() {
+		//根据自定义策略重试
+		String result = RetryUtil.ofPredicate(
+			() -> {
+				System.out.println(123);
+//				int a = 1 / 0;
+				return "ok";
+			},
+			5,
+			Duration.ofSeconds(1),
+			() -> {
+				System.out.println("兜底");
+				return "do";
+			},
+			(r, e) -> {
+				System.out.println("r = " + r);
+				System.out.println("e = " + e);
+				return r.equals("ok");
+			}
+		);
+
+		Assertions.assertEquals("ok", result);
+	}
+
+}