From bdc964c882b6fd1bee747406f4cbd2301b9b3acf Mon Sep 17 00:00:00 2001
From: Looly <loolly@aliyun.com>
Date: Tue, 26 Mar 2024 18:13:41 +0800
Subject: [PATCH] =?UTF-8?q?=E4=BC=98=E5=8C=96ThreadUtil.safeSleep=EF=BC=8C?=
 =?UTF-8?q?=E4=BD=BF=E7=94=A8System.nanoTime()?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../dromara/hutool/core/thread/ThreadUtil.java   | 16 ++++++----------
 .../hutool/core/thread/ThreadUtilTest.java       |  9 +++++++++
 2 files changed, 15 insertions(+), 10 deletions(-)

diff --git a/hutool-core/src/main/java/org/dromara/hutool/core/thread/ThreadUtil.java b/hutool-core/src/main/java/org/dromara/hutool/core/thread/ThreadUtil.java
index facf19ff0..356573018 100644
--- a/hutool-core/src/main/java/org/dromara/hutool/core/thread/ThreadUtil.java
+++ b/hutool-core/src/main/java/org/dromara/hutool/core/thread/ThreadUtil.java
@@ -490,7 +490,7 @@ public class ThreadUtil {
 	/**
 	 * 考虑{@link Thread#sleep(long)}方法有可能时间不足给定毫秒数，此方法保证sleep时间不小于给定的毫秒数
 	 *
-	 * @param millis 给定的sleep时间
+	 * @param millis 给定的sleep时间（毫秒）
 	 * @return 被中断返回false，否则true
 	 * @see ThreadUtil#sleep(Number)
 	 * @since 5.3.2
@@ -498,18 +498,14 @@ public class ThreadUtil {
 	public static boolean safeSleep(final long millis) {
 		long done = 0;
 		long before;
-		long spendTime;
-		while (done >= 0 && done < millis) {
-			before = System.currentTimeMillis();
+		// done表示实际花费的时间，确保实际花费时间大于应该sleep的时间
+		while (done < millis) {
+			before = System.nanoTime();
 			if (!sleep(millis - done)) {
 				return false;
 			}
-			spendTime = System.currentTimeMillis() - before;
-			if (spendTime <= 0) {
-				// Sleep花费时间为0或者负数，说明系统时间被拨动
-				break;
-			}
-			done += spendTime;
+			// done始终为正
+			done += (System.nanoTime() - before) / 1_000_000;
 		}
 		return true;
 	}
diff --git a/hutool-core/src/test/java/org/dromara/hutool/core/thread/ThreadUtilTest.java b/hutool-core/src/test/java/org/dromara/hutool/core/thread/ThreadUtilTest.java
index ba72a9398..ebaefe6fd 100644
--- a/hutool-core/src/test/java/org/dromara/hutool/core/thread/ThreadUtilTest.java
+++ b/hutool-core/src/test/java/org/dromara/hutool/core/thread/ThreadUtilTest.java
@@ -101,4 +101,13 @@ public class ThreadUtilTest {
 			}, "线程 - " + x).start();
 		}
 	}
+
+	@Test
+	void safeSleepTest() {
+		final long sleepMillis = RandomUtil.randomLong(1, 1000);
+		// 随机sleep时长，确保sleep时间足够
+		final long l = System.currentTimeMillis();
+		ThreadUtil.safeSleep(sleepMillis);
+		Assertions.assertTrue(System.currentTimeMillis() - l >= sleepMillis);
+	}
 }