fix code

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

@@ -0,0 +1,13 @@
+package cn.hutool.core.collection;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+public class MemorySafeLinkedBlockingQueueTest {
+
+	@Test
+	public void offerTest(){
+		final MemorySafeLinkedBlockingQueue<String> queue = new MemorySafeLinkedBlockingQueue<>(Integer.MAX_VALUE);
+		Assert.assertFalse(queue.offer("123"));
+	}
+}

hutool-core/src/test/java/cn/hutool/core/thread/SimpleSchedulerTest.java

@@ -0,0 +1,37 @@
+package cn.hutool.core.thread;
+
+import cn.hutool.core.io.FileUtil;
+import cn.hutool.core.lang.Console;
+import cn.hutool.core.util.RuntimeUtil;
+
+/**
+ * 简单定时任务测试
+ */
+public class SimpleSchedulerTest {
+	public static void main(final String[] args) {
+
+		// 新建一个定时任务，定时获取内存信息
+		final SimpleScheduler<Long> scheduler = new SimpleScheduler<>(new SimpleScheduler.Job<Long>() {
+			private volatile long maxAvailable;
+
+			@Override
+			public Long getResult() {
+				return this.maxAvailable;
+			}
+
+			@Override
+			public void run() {
+				this.maxAvailable = RuntimeUtil.getFreeMemory();
+			}
+		}, 50);
+
+		// 另一个线程不停获取内存结果计算值
+		ThreadUtil.execAsync(() -> {
+			//noinspection InfiniteLoopStatement
+			while (true) {
+				Console.log(FileUtil.readableFileSize(scheduler.getResult()));
+				ThreadUtil.sleep(1000);
+			}
+		});
+	}
+}